INSTALLATION INSTRUCTION

Transcription

1 INSTALLATION INSTRUCTION TWO-STAGE ULTRA MID-EFFICIENCY GAS-FIRED VARIABLE SPEED FURNACES Upfow / Horizonta Modes: P*DU - V / G8V Up To 130 MBH Output CONTENTS GENERAL INFORMATION... 3 UNIT INSTALLATION... 4 VENTING... 6 UPFLOW/HORIZONTAL MODELS... 8 UPFLOW / HORIZONTAL MODELS GAS PIPING OPERATION AND MAINTENANCE TROUBLESHOOTING WIRING DIAGRAM - UPFLOW/HORIZONTAL MODELS CAUTION: READ ALL SAFETY GUIDES BEFORE YOU START TO INSTALL YOUR FURNACE. SAVE THIS MANUAL

2 CONTENTS IMPROPER INSTALLATION MAY CREATE A CONDITION WHERE THE OPERATION OF THE PRODUCT COULD CAUSE PERSONAL INJURY OR PROPERTY DAMAGE. IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE CAN CAUSE INJURY OR PROPERTY DAMAGE. REFER TO THIS MANUAL FOR ASSISTANCE OR ADDITIONAL INFORMATION, CONSULT A QUALIFIED INSTALLER, SERVICE AGENCY OR THE GAS SUPPLIER. THIS PRODUCT MUST BE INSTALLED IN STRICT COMPLIANCE WITH THE ENCLOSED INSTALLATION INSTRUCTIONS AND ANY APPLICABLE LOCAL, STATE, AND NATIONAL CODES INCLUDING BUT NOT LIMITED TO, BUILDING, ELECTRICAL AND MECHANICAL CODES. The furnace area must not be used as a broom coset or for any other storage purposes, as a fire hazard may be created. Never store items such as the foowing on, near, or in contact with the furnace. 1. Spray or aeroso cans, rags, brooms, dust mops, vacuum ceaners or other ceaning toos. 2. Soap powders, beaches, waxes or other ceaning compounds; pastic items or containers; gasoine, kerosene, cigarette ighter fuid, dry ceaning fuids or other voatie fuid. 3. Paint thinners and other painting compounds. 4. Paper bags, boxes or other paper products Never bypass the safety mechanism to operate the furnace with the bower door removed. To do so coud resut in serious persona injury and/or equipment damage. GENERAL INFORMATION... 3 DESCRIPTION... 3 INSPECTION... 3 NOTES, CAUTIONS & WARNINGS... 3 LIMITATIONS AND LOCATION... 3 UNIT INSTALLATION... 4 COMBUSTION AIR... 4 VENTING... 6 CATEGORY I VERTICAL VENTING... 6 VENT SAFETY CHECK PROCEDURE... 6 DUCTWORK... 8 UPFLOW/HORIZONTAL MODELS... 8 UPFLOW APPLICATION... 8 FILTERS INSTALLATION... 8 UPFLOW / HORIZONTAL MODELS HORIZONTAL APPLICATION ATTIC INSTALLATION CRAWL SPACE INSTALLATION GAS PIPING ELECTRICAL POWER CONNECTION ELECTRICAL CONTROL CONNECTIONS SAFETY CONTROLS STARTUP AND ADJUSTMENTS IGNITION SYSTEM CHECKOUT/ADJUSTMENT CHECKING GAS INPUT ADJUSTMENT OF MANIFOLD GAS PRESSURE ADJUSTMENT OF TEMPERATURE RISE HEATING AIRFLOW COOLING AIRFLOW ADJUSTMENT OF FAN-OFF CONTROL SETTINGS ACCESSORY CONNECTIONS OPERATION AND MAINTENANCE SEQUENCE OF OPERATION CONTINUOUS BLOWER HEATING OPERATIONAL SEQUENCE MAINTENANCE BLOWER CARE CLEANING THE HEAT EXCHANGER TROUBLESHOOTING TROUBLESHOOTING THE BLOWER ASSEMBLY NO AIRFLOW OR MOTOR DOESN T RUN MOTOR ROCKS BUT WON T START MOTOR OPERATION IS INTERMITTENT MOTOR RUNS WHEN IT IS SUPPOSED TO BE OFF MOTOR STARTS BUT: RUNS ERRATICALLY MOTOR HUNTS OR PUFFS STAYS AT LOW CFM DESPITE SYSTEM CALL - COOL OR HEAT CFM.. 23 STAYS AT HIGH CFM BLOWER WON T SHUT OFF EXCESSIVE NOISE AIR NOISE REPLACEMENT OF FAILED MOTOR CONTROL MODULE BLOWER REMOVAL FOR CONTROLLER REPLACEMENT REPLACE VARIABLE SPEED MOTOR W/MULTI-SPEED MOTOR REMOVE VARIABLE SPEED BLOWER ASSEMBLY AND MOTOR INSTALLATION OF PSC MOTOR FURNACE CONTROL DIAGNOSTICS WIRING DIAGRAM - UPFLOW/HORIZONTAL MODELS Unitary Products Group

3 GENERAL INFORMATION DESCRIPTION This Category I furnace is designed for instaation in a residentia or commercia appication. A Category I furnace has a fan assisted combustion system equipped with an integra mechanica means to draw products of combustion through the combustion chamber and heat exchanger. It may be instaed in a basement, garage, equipment room, acove, attic or any other indoor ocation where a required cearances to combustibes and other restrictions are met. It is designed for natura gas fired operation, for use in standard and Lo Nox appications. High atitude and propane (LP) changes or conversions required in order for the appiance to satisfactoriy meet the appication must be made by an authorized contractor: in Canada, a certified conversion station or other quaified agency, using factory specified and/or approved parts. The bower in this furnace is programmed to suppy a constant voume of airfow to compensate for duct system static. The furnace must be instaed so that a eectrica components are protected from water. This appiance is not to be used for temporary heating of buidings or structures under construction. Do not insta this furnace in a corrosive or contaminated atmosphere. Do not insta this furnace in a mobie home or recreationa vehice. Furnaces sha not be instaed directy on carpeting, tie or other combustibe materia other than wood fooring. LIMITATIONS AND LOCATION This furnace shoud be instaed in accordance with a nationa/oca buiding/safety codes and requirements, or in the absence of oca codes, with the Nationa Fue Gas Code, ANSI Z223.1 (atest edition) or, in Canada, CAN/CGA B149.1 or.2 (atest edition), and other appicabe codes. Use ony the type of gas approved for this furnace; refer to the furnace rating pate. INSPECTION As soon as a unit is received, it shoud be inspected for possibe damage during transit. If the damage is evident, the extent of the damage shoud be noted on the carrier s freight bi. A separate request for inspection by the carrier's agent shoud be made in writing. Aso, before instaation, the unit shoud be checked for screws or bots which may have oosened in transit. NOTES, CAUTIONS & WARNINGS The instaer shoud pay particuar attention to the words: NOTE, CAUTION and WARNING. NOTES are intended to carify or make the instaation easier. CAUTIONS are given to prevent equipment damage. WARNINGS are given to aert the instaer that persona injury and/or equipment or property damage may occur if instaation procedures are not handed propery. Each furnace in this series is a Category I furnace, suitabe for common venting with other gas-fired appiances as aowed by the Nationa Fue Gas Code, NFPA 54/ANSI Z223.1atest edition. Ony use natura gas in furnaces designed for natura gas. Do not use this furnace with butane. Using wrong gas coud create a hazard, resuting in damage, injury or death. For instaations above 2,000 feet, reduce input 4% for each 1,000 feet above sea eve. Canadian instaations must be derated 10% for eevations from 2,000 ft. to 4,500 ft. See Form N1.1V for information to propery derate furnace. Furnace sha not be connected to a chimney fue serving a separate appiance designed to burn soid fue. Check the rating pate and power suppy to be sure that eectrica characteristics match. A modes use nomina 115 vac, 1 phase, 60 Hz. power suppy. A furnace instaed in a residentia garage must be ocated so that a burners and burner ignition devices are ocated no ess than 18" above the garage foor, and ocated or protected to prevent damage by vehices. The size of the unit shoud be based on an acceptabe heat oss cacuation for the structure. ACCA, Manua J or other approved methods may be used. Unitary Products Group 3

4 The furnace shoud be ocated using these guideines: 1. Where a minimum amount of vent piping and ebows wi be required. 2. As centraized with the air distribution as possibe. 3. Where adequate combustion air wi be avaiabe. 4. In an area where ventiation faciities provide for safe imits of ambient temperature under norma operating conditions. 5. Where it wi not interfere with proper air circuation in the confined space. 6. Where the vent wi not be bocked or restricted. 7. Where sufficient space is provided to aow proper service access. Minimum recommended service cearances are as foows: Twenty four (24) inches between the front of the furnace and an adjacent wa or another appiance, when access is required for servicing and ceaning. Eighteen (18) inches at the side where access is required for passage to the front when servicing or for inspection or repacement of fue/vent connections. 8. Where it wi not interfere with the ceaning, servicing or remova of other appiances. 9. Where the foowing minimum cearances (in inches) to combustibes can be maintained. Pease see, Tabe 1 on page 5. UNIT INSTALLATION COMBUSTION AIR A instaations must compy with Section 5.3, Air for Combustion and Ventiation of the Nationa Fue Gas Code, ANSI Z223.1 or Sections 7.2, 7.3 or 7.4 of CAN/CGA B149.1 or.2 Instaation Code atest editions. An unconfined space is not ess than 50 cubic feet per 1000 Btu/hr input rating for a appiances instaed in that area. Rooms communicating directy with the space containing the appiances are considered part of the unconfined space, if openings are not furnished with doors. A confined space is an area with ess than 50 cubic feet per 1000 Btu/hr input rating for a appiances instaed in that area. The foowing must be considered to obtain proper air for combustion and ventiation in confined spaces. Air Source from Inside the Buiding - Two permanent openings, one within 12 inches of the top of the confined space and one within 12 inches of the bottom, sha each have a free area of not ess than one square inch per 1,000 Btuh of tota input rating of a appiances ocated in the space. The openings sha communicate freey with interior areas having adequate infitration from the outside. NOTE:: At east 100 square inches free area sha be used for each opening. Air Source from Outdoors 1. Two permanent openings, one within 12 inches of the top of the confined space and one within 12 inches of the bottom, sha communicate directy, or by means of ducts, with the outdoors or to such craw or attic spaces that freey communicate with the outdoors. a. Vertica Ducts: Each opening must have a free area of not ess than one square inch per 4,000 Btuh of tota input of a appiances ocated in the space. EXAMPLE: Tota Input of A Appiances 4000 b. Horizonta Ducts: Each opening must have a free area of not ess than one square inch per 2,000 Btuh of tota input of a appiances ocated in the space. NOTE: Ducts must have the same cross sectiona area as the free area in the opening to which they are connected. The minimum dimension of rectanguar ducts sha be three inches. 2. One permanent opening, commencing within 12 inches of the top of the encosure sha be permitted where the equipment has cearances of at east 1 inch from the sides and back and 6 inches from the front of the appiance. The opening sha communicate through a vertica or horizonta duct to the outdoors, or spaces (craw or attic) that freey communicate with the outdoors and sha have a minimum free area of: a. 1 sq. in. per 3000 Btu per hr of the tota input rating of a equipment ocated in the encosure. b. Not ess than the sum of the areas of a vent connectors in the confined space. 3. Louvers, Gries and Screens = Square Inches Free Area a. In cacuating free area, consideration must be given to the bocking effects of ouvers, gries and screens. 4 Unitary Products Group

5 TABLE 1: UNIT CLEARANCES TO COMBUSTIBLES APPLICATION TOP FRONT REAR LEFT SIDE RIGHT SIDE FLUE FLOOR/ BOTTOM CLOSET ALCOVE ATTIC LINE CONTACT UPFLOW/HORIZONTAL MODELS - UPFLOW APPLICATION UPFLOW COMBUSTIBLE YES YES YES NO UPFLOW B-VENT COMBUSTIBLE YES YES YES NO HORIZONTAL APPLICATION HORIZONTAL COMBUSTIBLE NO YES YES YES 3 HORIZONTAL B-VENT COMBUSTIBLE NO YES YES YES /2 cabinet modes ony - a other units 0 cearance /2 cabinet eft airfow appications ony - a other units and a right hand air fow appications 0 cearance. 3. Line contact ony permitted between ines formed by the intersection of the rear pane and side pane (top in horizonta position) of the furnace jacket and buiding joists, studs or framing. b. If the free area of a specific ouver or grie is not known, refer to Tabe 2 to estimate free area. TABLE 2: ESTIMATED FREE AREA Wood or Meta Louvers or Gries Screens 2 1. Do not use ess than 1/4 in. mesh NOTE: If mechanicay operated ouvers are used, a means to prevent main burner ignition and operation must be provided shoud ouvers cose during startup or operation. Specia Combustion and Ventiation Considerations Operation of a mechanica exhaust, such as an exhaust fan, kitchen ventiation system, cothes dryer or firepace may create conditions requiring specia attention to avoid unsatisfactory operation of gas appiances. Speciay Engineered Instaations The above requirements sha be permitted to be waived where specia engineering, approved by the authority having jurisdiction, provides an adequate suppy of air for combustion, ventiation and diution of fue gases. Combustion Air Quaity Wood 20-25% 1 Meta 60-70% 1 1/4 in. mesh or arger 100% 2. Free area or ouvers an gries varies widey; instaer shoud foow ouver or grie manufacturer s instructions. The recommended source of combustion air is to use the outdoor air suppy. Excessive exposure to contaminated combustion air wi resut in safety and performance reated probems. However, the use of indoor air in most appications is acceptabe, except as foows: 1. If the furnace is instaed in a confined space it is recommended that the necessary combustion air come from the outdoors by way of attic, craw space, air duct or direct opening. 2. If outdoor combustion air is used, there must be no exposure to the instaations or substances isted in number 3 beow. 3. The foowing types of instaations may require OUT- DOOR AIR for combustion, due to chemica exposure. a. Commercia buidings b. Buidings with indoor poos c. Furnaces instaed in aundry rooms d. Furnaces instaed in hobby or craft rooms e. Furnaces instaed near chemica storage areas Exposure to the foowing substances in the combustion air suppy may aso require OUTDOOR AIR for combustion. f. Permanent wave soutions g. Chorinated waxes and ceaners h. Chorine based swimming poo chemicas i. Water softening chemicas j. De-icing sats or chemicas k. Carbon tetrachoride. Haogen type refrigerants m. Ceaning sovents (such as perchoroethyene) n. Printing inks, paint removers, varnishes, etc. o. Hydrochoric acids p. Cements and gues q. Antistatic fabric softeners for cothes dryers r. Masonry acid washing chemicas Unitary Products Group 5

6 VENTING VENT SAFETY CHECK PROCEDURE It is the responsibiity of the instaer to verify proper vent system operation. CATEGORY I VERTICAL VENTING Category I venting consists of verticay venting one or more appiances in B-vent or masonry chimney (as aowed), using singe wa meta pipe or B-vent connectors. Type B-vent system extends in a genera vertica direction and does not contain offsets exceeding 45 degrees, except that a vent system having not more than one 60 degree offset is permitted. NOTE: This appiance may be common vented with another gas appiance as aowed by the foowing codes and standards. The furnace rating pate ists the maximum vent gas temperature. This temperature must be used to seect appropriate venting materias and cearances. A typica exampe is shown on page 7. CATEGORY F. MAX. VENT TEMP. A instaations must be vented in accordance with the Nationa Fue Gas Code, NFPA 54/ANSI Z223.1 atest edition. For reference, the Nationa Fue Gas Code Handbook, avaiabe from NFPA (item JP54HB96) is recommended. The appiance must aso be vented in compiance with a oca utiity and code requirements. In Canada, the furnace must be vented in accordance with the Nationa Standard of Canada, CAN/CGAB149.1 and.2 atest editions. A furnace sha not be connected to a chimney fue serving a separate appiance designed to burn soid fue. If this furnace is repacing a common vented furnace, it may be necessary to resize the existing vent ine and chimney to prevent oversizing probems for the new combination of units. Refer to the Nationa Fue Gas Code, ANSI Z223.1 or CAN/ CGA B149.1 or.2 Instaation Code atest editions. The foowing steps sha be foowed with each appiance connected to the venting system paced in operation, whie any other appiances connected to the common venting system are not in operation. 1. Sea any unused openings in the common venting system. 2. Inspect venting system for proper size and horizonta pitch, as required in the Nationa Fue Gas Code ANSI Z223.1 or the CAN/CGA B149 Instaation Codes and these instructions. Determine that there is no bockage or restriction, eakage, corrosion or other deficiencies which coud cause an unsafe condition. 3. Insofar as is practica, cose a buiding doors and windows and a doors between the space in which the appiance(s) connected to the venting system are ocated and other spaces of the buiding. Turn on cothes dryers and any other appiances not connected to the common venting system. Turn on any cothes dryers and any appiance not connected to the venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts so they wi operate at maximum speed. Do not operate a summer exhaust fan. Cose firepace dampers. 4. Foow the ighting instructions. Pace the appiance being operated in operation. Adjust thermostat so appiance wi operate continuousy. 5. Test for draft hood equipped appiance spiage at the draft hood reief opening after 5 minutes of main burner operation. Use the fame of a match or cande. 6. After it has been determined that each appiance connected to the venting system propery vents when tested as outined above, return doors, windows, exhaust fans, firepace dampers and any other gas burning appiance to their previous conditions of use. 7. If improper venting is observed during any of the above tests, the venting system must be corrected. 8. Any corrections or resizing of the common venting system must be in accordance with the Nationa Fue Gas Code, ANSI Z223.1 or Section 7, Venting Systems and Air Suppy for Appiances, CAN/CGA B149.1 or.2 Insta- 6 Unitary Products Group

7 B 3/4 20 D (Vent Connection) 13-3/4 POWER WIRING 7/8" HOLE 2-1/2 5-3/8 14-3/4 40 GAS INLET 1-1/4" X 2-1/2" ACCESS WIRING 7/8" K.O. 2 OPTIONAL SIDE RETURN CUT-OUT (EITHER SIDE) 8-3/ / /2 2-1/4 1-1/8 FRONT A 28-1/2 LEFT SIDE T'STAT WIRING 7/8" K.O. RIGHT SIDE * ) + P*DU-V / G8V-UH MODEL A B C D E F 80/64/1200/ A 14-1/2 13-1/4 10-1/ /8 3-3/4 100/80/1600/ B 17-1/2 16-1/4 15-1/ /8 3-3/4 8 A J + A? J E L A JI E A, &! , 100/80/2000/ C /4 16-5/ /8 3-3/4 120/96/2000/ C /4 16-5/ /8 3-3/ ) / * ) / ! ". ) -/ ALL DIMENSIONS ARE IN INCHES, AND ARE APPROXIMATE. FIGURE 1: 2-STAGE UPFLOW/HORIZONTAL FURNACE DIMENSIONS TABLE 3: TWO STAGE UPFLOW / HORIZONTAL RATINGS & PHYSICAL/ELECTRICAL DATA P*DU-V / G8V-UH INPUT MBH H/L OUTPUT MBH H/L NOM. CFM CABINET WIDTH (IN.) AFUE 1 LOW FIRE TEMP RISE F HIGH FIRE TEMP RISE F MAX. OUTLET AIR TEMP. F HP BLOWER AMPS SIZE (IN.) TOTAL UNIT AMPS MAX. OVER- CURRENT PROTECT 2 MIN WIRE SIZE 75 FT. ONE WAY 2 OPER. WGT (LBS) 80/59 64/ A 14-1/ / x /65 80/ B 17-1/ / x /65 80/ C x /78 96/ C x AFUE numbers are determined in accordance with DOE test procedures 2. Wire size and overcurrent protection must compy with the Nationa Eectrica Code (NFPA-70-atest edition). For atitudes above 2,000 ft., reduce capacity 4% for each 1,000 ft. above sea eve. Refer to Form N1.1V. Wire size based on copper conductors, 60 C, 3% votage drop. Continuous return air temperature must not be beow 55 F. Unitary Products Group 7

8 ation Code atest editions. If the common vent system must be resized, it shoud be resized to approach the minimum size as determined using the appropriate tabes in Appendix G of the above codes or the venting tabes suppied with the furnace. DUCTWORK The duct system's design and instaation must: 1. Hande an air voume appropriate for the served space and within the operating parameters of the furnace specifications. 2. Be instaed in accordance with standards of NFPA (Nationa Fire Protection Association) as outined in NFPA pamphets 90A and 90B (atest editions). 3. Create a cosed duct system. The suppy system must be connected to the furnace outet and the return duct system must be connected to the furnace inet. Both suppy and return duct systems must terminate outside the space containing the furnace. 4. Generay compete a path for heated or cooed air to circuate through the air conditioning and heating equipment and to and from the conditioned space. UPFLOW/HORIZONTAL MODELS UPFLOW APPLICATION Suppy Penum Connection Attach the suppy penum to the furnace outet duct connection fanges. This is typicay through the use of S ceat materia when a meta penum is used. The use of an approved fexibe duct connector is recommended on a instaations. This connection shoud be seaed to prevent air eakage. If a matching cooing coi is used, it may be paced directy on the furnace outet and seaed to prevent eakage. Foow the coi instructions for instaing the suppy penum. On a instaations without a coi, a removabe access pane is recommended in the outet duct such that smoke or refected ight woud be observabe inside the casing to indicate the presence of eaks in the heat exchanger. This access cover sha be attached in such a manner as to prevent eaks. Return Duct Connection The cooing coi must be instaed in the suppy air duct downstream of the furnace. When the furnace is used in conjunction with a cooing coi, the furnace must be instaed in the suppy air duct downstream of the furnace.1 When a parae fow arrangement is used, the dampers or other means used to contro air fow must be adequate to prevent chied air from entering the furnace, and if manuay operated, must be equipped with means to prevent operating of either unit uness the damper is in the fu heat or coo position. Return air may enter the furnace through the side(s) or bottom depending on the type of appication. Return air may not be connected into the rear pane of the unit. See the specific type appication instaation for detais. Be sure to see the Fiters section of this instruction. FILTERS INSTALLATION (UPFLOW/HORIZONTAL) A appications require the use of a fiter. A high veocity fiter and retainer are provided for fied instaation. Interna Instaation 1. Seect desired fiter position (eft/right side, or bottom). Remove the corresponding cabinet cutouts per instructions provided. Refer to Figure 4 on page Insta snap-in retainer cips into the corresponding sots from the outside rear of the cabinet, refer to Figure 2 on page 9. To prevent cabinet air eaks, insta snap-in pugs (provided) into the unused sots at the outside rear of the cabinet. 3. Insta the wire retainer inside the cabinet. Insert the open ends of the wire retainer into the cip oops at the rear of the bower compartment. The retainer wire shoud pivot freey ike a hinge, on the cips at the rear of the cabinet. Refer to Figure 3 on page 9 8 Unitary Products Group

9 Side Return Externa Fiter FURNACE (REARCABINET) Locate and knock out the square corner ocators. These indicate the size of the cutout to be made in the furnace side pane, refer to Figure 4. RIGHT SIDE SLOTS LEFT SIDE SLOTS BOTTOMSLOTS CABINET SLOT FILTERSUPPORT CLIPS(PROVIDED) PLUGUNUSED CABINETSLOTS WITHPLUGS (PROVIDED) FIGURE 2 : CLIPS FURNACE FILTER SLOT LOCATIONS POSITIONWIRERETAINER (PROVIDED)UNDERFLANGE FILTER (PROVIDED RIGHTSIDE INSTALLATION FURNACE SHOWN FRONT CORNER MARKINGS FRONT OF FURNACE FIGURE 4 : SIDE RETURN CUTOUT MARKINGS Insta the side fiter rack foowing the instructions provided with that accessory. If a fiter(s) is provided at another ocation in the return air system, the ductwork may be directy attached to the furnace side pane. NOTE: Some accessories such as eectronic air ceaners and peated media may require a arger side opening. FIGURE 3 : SIDE FILTER RETAINER PLACEMENT 4. Insta the fiter(s) provided. Cut fiter if necessary to match air opening in cabinet. Fiter shoud extend beyond opening edge as much as possibe to prevent air from bypassing the fiter. DO NOT remove stiffening rods from inside the fiter. Shorten the rods, if necessary, to match fina fiter size. 5. Position the fiter between the wire retainer and the cabinet wa (or foor) so it competey covers the cabinet air opening and secure the fiter in pace at the front of the cabinet by fastening the cosed (ooped) end of the retainer wire under the fanged edge of the cabinet. When propery instaed the fiter shoud fit fush with a four sides of the cabinet wa. NOTE: Air veocity through throwaway type fiters may not exceed 300 feet per minute. A veocities over this require the use of high veocity fiters. A instaations must have a fiter instaed. The return duct may be attached to the furnace by S-ceat, bend tabs or other approved methods. Be sure to sea the duct to the furnace to prevent air eakage. In order to achieve the airfow indicated in the tabe, it is recommended for those appications over 1800 CFM use return from two sides, one side and the bottom, or bottom ony. For bottom ony appication, see data and notes on bower performance tabes in this manua. Where the return duct system is not compete, the return connection must run fu size to a ocation outside the utiity room or basement. For further detais, consut Section 5.3 (Air for Combustion and Ventiation) of the Nationa Fue Gas Code, ANSI Z223.1, or CAN/CGA B149.1 or.2, Instaation Code atest editions. Unitary Products Group 9

10 Bottom Return Bottom return appications normay pu return air through a base patform or return air penum. Be sure the return patform structure is suitabe to support the weight of the furnace. Refer to Figure 1 on page 7 for unit dimensions and Tabe 3 on page 7 for unit weights. Be sure to sea the furnace to penum connection to prevent air eakage. For horizonta appication, return air may enter through the bottom, eft side or right side pane or any combination of these openings. Return air may not be connected into the rear pane of the unit. To convert the upfow mode furnace to open bottom,see Bottom Return section of this manua. The bottom pane is equipped with a perforated opening for easy remova. Tabs must be cut with sheet meta snips to aow removing knockout. Scribe marks are incuded for forming fanges for attachment of the return air ductwork. LINE CONTACT ONLY PERMISSIBLE BETWEEN LINES FORMED BY THE INTERSECTION OF FURNACE TOP AND TWO SIDES AND BUILDING JOISTS, STUDS OR FRAMING SUPPLY AIR NOTE: If an externa mounted fiter rack is being used, see the instructions provided with that accessory for proper hoe cut size. Upfow attic instaations must meet a minimum cearances to combustibes and have foor support with required service accessibiity. GAS PIPING 12" 30" MIN WORK AREA VENT (MAINTAIN REQUIRED CLEARANCES TO COMBUSTIBLES) SHEET METAL IN FRONT OF FURNACE COMBUSTION AIR OPENINGS IS RECOMMENDED UPFLOW / HORIZONTAL MODELS - HORIZONTAL APPLICATION RETURN AIR SEDIMENT TRAP FIGURE 5 : TYPICAL ATTIC INSTALLATION ATTIC INSTALLATION This appiance is design certified for ine contact for furnaces instaed horizontay. The intersection of the furnace top and sides form a ine. NOTE: If an externa mounted fiter rack is being used, see the instructions provided with that accessory for proper hoe cut size. Upfow attic instaations must meet a minimum cearances to combustibes and have foor support with required service accessibiity. This ine may be in contact with combustibe materia. However, VENTING" Section on page 6 in this manua for additiona information. Secure a patform constructed of pywood or other buiding materia to the foor joists. Sheet meta, 12" in front of the furnace combustion air openings is recommended. Refer to Figure 6 on page 11. Upfow furnaces may be instaed horizontay with the suppy airfow toward the eft or right by aying the unit on the eft or right side pane. Do not insta the unit on the rear pane. After determining the best orientation, ay the unit on top of the shipping carton to protect the finish. When a furnace is instaed in an attic or other insuated space, keep a insuating materias at east 12" away from furnace and burner combustion air openings. NOTE: See craw space instaation for suspending the furnace in attic instaations. The appropriate eectrica knock-outs for power wiring, contro wiring and gas piping shoud be removed at this time. 10 Unitary Products Group

11 during any pressure testing of the gas suppy piping system at test pressures equa to or ess than 1/2 psig (3.48 kpa). ANGLEIRON BRACKET SUPPORT ROD Never appy a pipe wrench to the body of the combination automatic gas vave. A wrench must be paced on the projection or wrench boss of the vave when instaing piping to it. 1"MAXBETWEEN ROD&FURNACE CRAWL SPACE INSTALLATION The furnace can be hung from foor hoists or instaed on suitabe bocks or pad. Bocks or pad instaations sha provide adequate height to ensure the unit wi not be subject to water damage. When suspending the furnace from rafters or foor joists using rod, pipe or straps, refer to Physica Data, Tabe 3 on page 7, for furnace weights to determine suitabe means of suspension. GAS PIPING 6"MINBETWEEN ROD&FURNACE 1"MAXBETWEEN ROD&FURNACE FIGURE 6 : TYPICAL FURNACE INSTALLATION USING SUSPENSION MATERIALS NOTE: An accessibe manua shutoff vave must be instaed upstream of the furnace gas contros and within 6 feet of the furnace. Gas piping may be connected from either side of the furnace. Sizing and instaation of the suppy gas ine shoud compy with the oca utiity requirements. The gas suppy shoud be a separate ine, instaed in accordance with the Nationa Fue Gas Code, ANSI Z223.1, or CAN/CGA B149.1 or.2 Instaation Codes (atest editions). Some utiity companies, or oca codes, require pipe sizes arger than the minimum sizes isted. Using the propery sized wrought iron, approved fexibe or stee pipe, make gas connections to the unit. Instaation of a drop eg and ground union is required, refer to Figure 7. INLET GAS PRESSURE RANGE NATURAL GAS PROPANE (LP) Minimum 4.5 In. W.C. 11 In. W.C. Maximum 13.8 In. W.C In. W.C. EXTERNALMANUAL SHUTOFF VALVE TOGAS SUPPLY An overpressure protection device, such as a pressure reguator, which conforms to the Nationa Fue Gas Code, ANSI Z223.1 (U.S.) or CANB149.1 or.2 (Canada) and acts to imit the downstream pressure to vaue that does not exceed 0.5 PSI (14" w.c.), must be instaed in the gas piping system upstream of the furnace. Faiure to do so may resut in a fire or exposion or cause damage to the furnace or some of its components. TOGAS SUPPLY GROUNDJOINT UNION MAY BE INSTALLED INSIDE OR OUTSIDE UNIT GAS VALVE DROP LEG The furnace and its individua shutoff vave must be disconnected from the gas suppy piping system during any pressure testing of that system at test pressures in excess of 1/2 psig (3.48 kpa). FIGURE 7 : GAS PIPING The furnace must be isoated from the gas suppy piping system by cosing its individua externa manua shutoff vave Unitary Products Group 11

12 Figure 8. The back furnace ead must be connected to the L1 (hot) wire from the power suppy. Compounds used on threaded joints of gas piping must be resistant to the action of iquefied petroeum gases. NOTE: a 1/8 NPT pug is incuded in the inet side of the gas vave for measuring incoming gas pressure. / / GRN/GRN HUM L1 (HOT) N GRD HUM (HOT) GRN EAC (HOT) After a gas piping connections are competed, eak test a joints, fittings and furnace connections with rich soap and water soution, commercia avaiabe bubbe type eak detection fuid, or other approved means. EAC WIRING INSIDE JUCTION BOX BURNER COMPARTMENT JUNCTION BOX Do not use an open fame or other source of ignition for eak testing. ELECTRICAL POWER CONNECTION Fied wiring to the unit must conform to and be grounded in accordance with the provisions of the Nationa Eectrica Code ANSI/NFPA No. 70 atest edition, Canadian Eectric Code C22.1 Part 1 (atest edition) and/or oca codes. Eectrica wires which are fied instaed sha conform with the temperature imitation for 63F/35C rise wire when instaed in accordance with instructions. Specific eectrica data is given on the furnace rating pate. Provide a power suppy separate from a other circuits. Insta overcurrent protection and disconnect switch per oca/ nationa eectrica codes. The switch shoud be reasonaby cose to the unit for convenience in servicing. With the disconnect switch in the OFF position, check a wiring against the unit wiring abe. Aso, see the wiring diagram in this instruction. NOTE: The furnace s contro system depends on correct poarity of the power suppy and a proper ground connection. Refer to the furnace contro diagnostics section for symptoms of reversed power suppy poarity. Use copper conductors ony. Connect the power suppy as shown on the unit wiring abe on the inside of the bower compartment door and refer to CFM/TIMER BOARD TRANSFORMER BLOWER COMPARTMENT IGNITION MODULE DOOR SWITCH FIGURE 8 : UPFLOW MODELS - ELECTRICAL WIRING CLASS 2 SYSTEM CONTROL WIRING TO THERMOSTAT The white furnace ead must be connected to neutra. Aso, the green equipment ground wire must be connected to the power suppy ground. Remove the screw retaining the junction box cover. Route the power wiring through the unit side pane with a conduit connector or other proper connection. Make wiring connections: Refer to Figure 8. Repace the wiring box cover and screw. An aternate wiring method is to use a fied provided 2 x 4 box and cover on the outside of the furnace. Route the furnace eads into the box using a protective bushing where the wires pass through the furnace pane. NOTE: The power connection eads and wiring box on upfow units may be reocated to the eft side of the furnace. Remove the screws and cut wire tie hoding excess wiring. Reposition on the eft side of the furnace and fasten using hoes provided. LINE LINE HUM EAC 12 Unitary Products Group

13 ELECTRICAL CONTROL CONNECTIONS Insta the fied suppied thermostat. The thermostat instructions for wiring are packed with the thermostat. With the thermostat set in the OFF position and the main eectrica source disconnected, compete the ow votage wiring from the thermostat to the termina board on the CFM programmabe board. Connect Cass 2 contro wiring: see Figure 9, for singe stage thermostat wiring: see Figure 10 for two stage thermostat wiring.. Set the heat anticipator in the room thermostat as shown beow. Setting it ower wi cause short cyces. Setting it higher wi cause the room temperature to exceed the setpoint. Two-Stage Thermostat First Stage.4 Amps Singe Stage Thermostat HUM Y2 Y1 Y R W1 W2 G C O X/L Second Stage TYPICAL FIELD WIRING - SINGLE STAGE SINGLE STAGE THERMOSTAT Y1 R W1 G C HEATPUMP HUMIDISTAT HUM Y2 Y1 Y R W1 W2 G C O X/L COOL.1 Amps.4 Amps CFM/TIMER BOARD HEAT DELAY ADJ W1 P9 P6 The 24vot, 40 VA transformer is sized for the furnace components ony, and shoud not be connected to auxiiary devices such as humidifiers, air ceaners, etc. The transformer may provide power for an air conditioning unit contactor. TWO STAGE THERMOSTAT Y2 Y1 R W1 W2 G C X\L TYPICAL FIELD WIRING - TWO STAGE CFM/TIMER BOARD FIGURE 10 : FIELD WIRING FOR TWO STAGE THERMOSTAT 24 Vot Connections HUM Y2 Y1 Y R W1 W2 G C O X/L TIME OFF MINUTE SELECT OUTDOOR UNIT Y2 Y1 Y2 OUT R C X\L JUMPER MUST BE IN TIMER OFF POSITION This variabe airfow furnace incudes a CFM programmabe board in the ower part of the eectrica contro box. A fied wiring connections shoud be made to this termina bock. TIME OFF MINUTE SELECT W2 TIME OFF MINUTE SELECT LOW HEAT TIME ADJUSTMENT DO NOT connect fied wiring to the furnace ignition contro modue or to the CFM Seection Board. FIGURE 9 : FIELD WIRING FOR SINGLE STAGE THERMOSTAT Appy strain reief to thermostat wires passing through the cabinet. NOTE: Some eectronic thermostats do not have adjustabe heat anticipators. They may have other type cyce rate adjustments. Foow the thermostat manufacturer's instructions. Connection diagrams are shown above in Figures 9 and 10. Seect the correct diagram for your particuar heating and cooing system. SAFETY CONTROLS Bower Door Safety Switch This unit is equipped with an eectrica interock switch mounted in the bower compartment. This switch interrupts a Unitary Products Group 13

14 power at the unit when the pane covering the bower compartment is removed. Bower and burner must never be operated without the bower pane in pace. Eectrica suppy to the unit is dependent upon the pane that covers the bower compartment being in pace and propery positioned. Auxiiary Limit Contros These high temperature imit contros are ocated in the bower compartment, one on each side on upfow/horizonta unit. Downfow units have a singe imit mounted on the bower assemby. These are manua reset contros and give high temperature protection when the unit is appied in the horizonta position. Contro Circuit Fuse A 3 amp fuse is provided to protect the 24 vot transformer from overoad caused by contro circuit wiring errors. This is an ATO 3, automotive type fuse and is ocated in the unit wiring harness between the contro transformer and the furnace contro. STARTUP AND ADJUSTMENTS Main power suppy to the unit must sti be interrupted at the main power disconnect switch before any service or repair work is to be done to the unit. Do not rey upon the interock switch as a main power disconnect. Roout Switch Contros These contros are mounted on the burner assemby. If the temperature in the burner compartment exceeds its set point, the ignitor contro and the gas vave are deenergized. This is a manua reset contro and must be reset before operation can continue. The operation of this contro indicates a mafunction in the combustion air bower or a bocked vent pipe connection. Pressure Switch This furnace is suppied with two differentia pressure switches which monitor the fow through the furnace and venting system. This switch de-energizes the ignition contro modue and the gas vave if any of the foowing conditions are present: 1. Bockage of interna fue gas passage ways. 2. Bockage of vent piping. 3. Faiure of combustion air bower/motor. Limit Contro The high temperature imit contro is ocated on the furnace vestibue pane just to the right and above the gas vave. This is an automatic reset contro and provides over temperature protection due to reduced airfow, such as a dirty fiter or bower motor faiure. The initia startup of the furnace requires the foowing additiona procedures. 1. When the gas suppy is initiay connected to the furnace, the gas piping may be fu of air. In order to purge this air, it is recommended that the ground joint union be oosened unti the odor of gas is detected. When gas is detected, immediatey retighten the union and check for eaks. Aow five minutes for any gas to dissipate before continuing with the startup procedure. 2. A eectrica connections made in the fied and in the factory shoud be checked for proper tightness. IGNITION SYSTEM CHECKOUT/ADJUSTMENT 1. Turn the gas suppy ON at externa vave and main gas vave. 2. Set the thermostat above room temperature to ca for heat. 3. System startup wi occur as foows: a. The ventor motor wi start and operate on ow speed. Shorty after ventor startup, the hot surface ignitor wi gow for about 17 seconds. b. After this warm-up cyce, the ignition modue wi energize (open) the main gas vave on ow fire for seven seconds. c. After fame is estabished, the suppy air bower wi start within 30 seconds. NOTE: Burner ignition may not be satisfactory on first startup due to residua air in gas ine, or unti gas pressure (manifod) is adjusted. 4. With the furnace in operation, paint the pipe joints and vave gasket ines with a rich soap and water soution. Bubbes indicate a gas eak. Take appropriate steps to 14 Unitary Products Group

15 stop the eaks. If the eak persists, repace the component. If the actua input is not within +2% of the furnace rating, with aowance being made for the permissibe range of the reguator setting (0.3 inches W.C.), repace the orifice spuds with spuds of the proper size. DO NOT omit this test! NEVER use a fame to check for gas eaks. Gas Vave Operation The manua vave knob is a two-position (ON-OFF) type. To turn the vave ON, rotate knob cockwise or countercockwise to ine up the word ON on the knob with the indicator on the cover casting. Refer to Figure 11 on page 16. CHECKING GAS INPUT 1. Turn off a other gas appiances connected to gas meter. 2. With the furnace turned on, measure the time needed for one revoution of the hand on the smaest dia on the meter. A typica domestic gas meter usuay has a 1/2 or 1 cubic foot test dia. 3. Using the number of seconds for each revoution and the size of the test dia increment, find the cubic feet of gas consumed per hour from Tabe 4 on page 16. NOTE: To find the Btuh input, mutipy the number of cubic feet of gas consumed per hour by the BTU content of the gas in your particuar ocaity. Contract your gas company for this information, as it varies widey from city to city. EXAMPLE: It is found by measurement that it takes 26 seconds for the hand to turn on the 1 cubic foot dia to make a revoution with ony a 120,000 Btuh furnace running. Using this information, ocate 26 seconds in the first coumn of Tabe 4. Read across to the coumn headed 1 Cubic Foot where you wi see that 138 cubic feet of gas per hour are consumed by the furnace at that rate. Mutipy 138 by 850 (the BTU rating of the gas obtained from the oca gas company). The resut is 117,300 Btuh, which is cose to the 120,000 Btuh rating of the furnace. Be sure to reight any gas appiances that were turned off at the start of this input check. ADJUSTMENT OF MANIFOLD GAS PRESSURE The reguated outet pressures, both ow and high, have been caibrated at the factory. Additiona pressure adjustment shoud not be necessary. If adjustment is necessary, set to the foowing specifications. Check high pressure before checking or adjusting ow pressure. After adjustment, check for gas eakage. Low Fire High Fire NATURAL GAS High Outet Pressure Adjustment 1.6 IWG 3.5 IWG 1. Turn off a eectrica power to the system at main fuse or circuit breaker. Cose manua gas vave. 2. Attach a manometer to the outet pressure tap of the vave. 3. Turn on power and energize main and redundant (P.M.) soenoids as we as the HI termina. Open manua gas vave. 4. Remove high adjustment sea screw to expose the 3/32 socket set screw, see Figure 11 on page To increase outet pressure, turn the 3/32 socket set screw cockwise. To decrease outet pressure, turn the set screw countercockwise. Adjust reguator unti pressure shown on manometer matches the pressure specified on the appiance rating pate. 6. Repace high adjustment sea screw and tighten securey. Cyce the vave two or three times to verify reguator setting. Unitary Products Group 15

16 TABLE 4 : GAS RATE (CUBIC FEET PER HOUR) SIZE OF TEST DIAL SECONDS FOR ONE REVOLUTION 1/2 CUBIC FOOT 1 CUBIC FOOT 8. Once the correct high outet gas pressure to the burners has been set adjust the ow outet pressure per the adjustment procedure detaied in the next section Be sure that the gas vave pressure reguator cap is repaced. Low Outet Pressure Adjustment 1. Adjust the thermostat so the furnace wi operate at ow fire. 2. Refer to Figure 11, for the ocation of the pressure reguator adjustment cap and screw on main gas vave. 3. Remove ow adjustment sea screw, see Figure Remove manometer and repace the outet pressure tap pug. LOW FIRE REGULATOR ADJUSTMENT SEAL SCREW HIGH FIRE REGULATOR ADJUSTMENT SEAL SCREW The manifod pressure must be checked with the screw-off cap in pace on the pressure reguator. If manifod pressure is too high, an overfire condition exists which coud cause heat exchanger faiure. If the manifod pressure is too ow, sooting and eventua cogging of the heat exchanger coud occur. FIGURE 11 : GAS VALVE - (Top) Manua Contro Knob (Bottom) Reguator Adjustments 4. To increase outet pressure, turn the 3/32 socket set screw beow the ow adjustment sea screw cockwise. 16 Unitary Products Group

17 To decrease outet pressure, turn the set screw countercockwise. Adjust reguator unti pressure shown on manometer matches the pressure specified on the appiance rating pate. 5. Repace ow adjustment sea screw and tighten securey. Cyce the vave severa times to verify reguator setting. 6. Turn off gas and eectricity and remove manometer and gas vave tap and repace the outet pressure tap pug. 7. Turn the eectrica and gas suppies back on, and with the burners in operation, check for gas eakage around the pug with a soap and water soution. the range shown on the furnace rating pate and within the appication imitations shown in Tabe 3 on page 7. HEATING AIRFLOW The heating airfow has been preset at the factory to provide maximum CFM. If a esser CFM is required for a specific HVAC system the JUMPER on the HEAT seection pins on the CFM-Timer Board may be moved to tap B or C, but not D. Pins A wi provide the highest CFM and C the owest CFM. Refer to Tabe 7 on page 27 for CFM options. ADJUSTMENT OF TEMPERATURE RISE Direct Drive Motors (ony appies to PSC repacement) The temperature rise, or temperature difference between the return air and the heated air from the furnace, must be within the range shown on the furnace rating pate. Appication imitations are shown in Tabe 1 or 2. After the temperature rise has been determined, the cfm can be cacuated. After about 20 minutes of operation, determine the furnace temperature rise. Take readings of both the return air and the heated air in the ducts, about six feet from the furnace where they wi not be affected by radiant heat. Increase the bower speed to decrease the temperature rise; decrease the bower speed to increase the rise. A direct-drive bowers have muti-speed motors. The bower motor speed taps are ocated in the contro box in the bower compartment. Refer to Figure 28 and the unit wiring abe to change the bower speed. You may seect a heating speed and a cooing speed. They may be the same speed or a different speed. To use the same speed tap for heating and cooing, the heat termina and coo termina must be connected using a jumper wire and connected to the desired motor ead. Pace a unused motor eads on Park terminas. Two Park terminas are provided. Do not energize more than one motor speed at a time or damage to the motor wi resut. Variabe Speed Motors The temperature rise, or temperature difference between the return air and the heated air from the furnace, must be within Heat Pin D shoud never be used for heating airfow as the furnace wi operate outside the rise range. NOTE:Power to the bower must be removed for at east 4 seconds after a heat or coo tap seection change, in order for the motor to recognize an adjustment. The fixed bower on deay and adjustabe bower-off deay wi function as described in the OPERATION AND MAINTENANCE" Section on page 18 of this instruction. COOLING AIRFLOW The Cooing airfow is preset at the factory to provide approximatey 90% of the maximum CFM and must be adjusted in the fied to match the HVAC system at instaation. Refer to the outdoor unit instaation instruction for the recommended airfow and Tabe 7 on page 27. The "DELAY" Tap shoud be set in the "B" position for a twostage condenser. This resuts in a 45 second off deay at 82% of the programmed cooing airfow with a 15-second coast to stop. It shoud be set in the "C" position for a system with a TXV or soenoid vave. This resuts in a 45 second off deay at 75% of the programmed cooing airfow with a 15-second coast to stop. It shoud be set in the "D" position for a system without a TXV or soenoid vave. This resuts in a 60 second off deay at 82% of the programmed cooing airfow with a 15- second coast to stop. The "A" position shoud not be used. ADJUSTMENT OF FAN-OFF CONTROL SETTINGS This furnace is equipped with a time-on/time-off heating fan contro. The fan-on is fixed at 30 seconds. The fan-off deay is factory set to 60 seconds, however, it is fied adjustabe to 90, 120, or 180 seconds. The fan-off setting must be ong enough to adequatey coo the furnace, but not so ong that cod air is bown into the heated space. Unitary Products Group 17

18 The continuous fan speed and the fan-off timing may be adjusted by setting the DIP switches ocated on the contro board as foows: (See Figure 12 and Tabe 5). TABLE 5 : FAN CONTROL SETTINGS 115 VOLT HUMIDIFIER HUM HOT WHI EAC HUM SWITCHED CIRCUITS IGNITION CONTROL To Set Continuous Fan Speed: Set Switch 3 EAC HOT Coo To Deay Fan-Off By: Off Set Switch VOLT ELECTRONIC AIR CLEANER WHI EAC HUM NEUTRALS 60 Sec. On-On 90 Sec. Off-On 120 Sec. On-Off 180 Sec. Off-Off BLU-MED SPEED RED - LOW SPEED MOTOR LEADS -HIGH SPEED FIGURE 13 : ACCESSORY CONNECTIONS Humidifier Connection Two 1/4 spade terminas (HUM and HUM N) for humidifier connections are ocated on the contro board. The terminas provide 115 VAC (1.0 amp maximum) during heating system operation. A high votage connection ead is routed to the junction box for easy connection. OPERATION AND MAINTENANCE COOL SEQUENCE OF OPERATION OFF 1 3 ON RED BLU PARK HEA T L O HEA T HI FIGURE 12 : TYPICAL HEAT/COOL SPEED TAP CONNECTIONS ACCESSORY CONNECTIONS The furnace contro wi aow power switching contro of various accessories. Refer to Figure 13 for connection detais. Eectronic Air Ceaner Connection FAN OFF ADJUSTMENT SWITCHES W1 W2 Y R G B Two 1/4 spade terminas (EAC and EAC N) for eectronic air ceaner connections are ocated on the contro board. The terminas provide 115 VAC (1.0 amp maximum) during circuating bower operation. A high votage connection ead is routed to the junction box for easy connection. The foowing describes the sequence of operation of the furnace as it reates to a furnace equipped with a variabe speed bower. Refer to the schematic wiring diagram on page 28 for component ocation. CONTINUOUS BLOWER There are two modes of continuous bower operation. In one mode the bower is controed directy through the bower motor. In the second mode the bower is controed through the ignition contro. In the first mode, when the thermostat fan-switch is set to the ON position a circuit is competed between terminas R and G of the thermostat. The continuous fan speed wi be 63% of the high coo speed. If more air is desirabe the green wire abed (G Coo Speed) may be connected to the G termina of the ignition contro to achieve HIGH COOL speed (DIP switch number 3 on the ignition contro must be in the OFF position). The air ceaner and the bower motor are energized through the ignition contro or directy through the motor. INTERMITTENT BLOWER COOLING On cooing/heating thermostats with fan switch, when the fan switch is set in the auto position and the thermostat cas for cooing, a circuit is competed between the R, Y and G terminas. The motor is energized through the Y1 coo termina and runs on the speed seected on the CFM / Timer board. 18 Unitary Products Group