UNIVERSITY OF CALIFORNIA, SAN DIEGO

Transcription

1 BERKELEY DAVIS IRVINE LOS ANGELES MERCED RIVERSIDE SAN DIEGO SAN FRANCISCO SANTA BARBARA SANTA CRUZ OFFICE OF THE ASSIST ANT VICE CHANCELLOR CAMPUS ARCHITECT- FACILITIES DESIGN & CONSTRUCTION TEL : (858) FAX : (858) GILMAN DRIVE #09I6 LA JOLLA, CALIFORNIA December 8, 2014 TO: ALL HOLDERS OF BIDDING DOCUMENTS TELECOM BLDG. HVAC UPGRADES Enclosed is the following: 1. Addendum No.2 dated December 8, 2014, to the Construction Documents. NOTE: THE BID DATE REMAINS 2:00P.M., WEDNESDAY, DECEMBER 17,2014. Gillie Senior Director of Construction Services Facilities Design and Construction.. -dim:ie's~. Enclosure

2 PROJECT NO.: 4606/MS-024/ General: ADDENDUM NO. TWO TO THE CONSTRUCTION DOCUMENTS December 8, 2014 The following changes, additions or deletions shall be made to the following documents; all other conditions shall remain the same. I. Item# CLARIFICATIONS 1. Question: What are the requirements for temporary cooling (i.e. load, electrical)? Answer: a. Requirements for temporary cooling are as listed below and the phasing is only a suggestion. The activities of the building must be maintained at all times and the noise disruption kept to a minimum. Rooms 108, 113, and 114 must be operational at all times. Employees in rooms 109, 110, and 112 can be relocated to allow for construction activities but must be coordinated with the owner regarding duration. Room 111 is vacant and can be used temporarily as an office, break room, or conference room depending on the sequence of work set by the contractor. Most of the work outlined can be conducted during regular business hours, but noise must be kept to a minimum and may need to be conducted after regular business hours if the owner decides the work is too disruptive: i. Phase 1 Scope of work: (E) AC-1 demo, AC-1A/18 install, MECHANICAL ROOM work (except FC-1 system), SWITCH ROOM work Temp cooling: (1) 5-ton unit for MECHANICAL ROOM. To avoid electrical overload, the temporary 5 ton moving cool unit may run simultaneously with either AC-1A or AC-18, but not both. Under no circumstance, should temporary 5 ton moving cool and new AC-1A and AC-18 be run simultaneously. User Requirements: Complete the work for rooms 113 and 114 and keep existing FC-1 running. ii. Phase 2 Scope of work: FC-3 install, FC-4 install, LOUNGE work, RECEPTION work, CONFERENCE ROOM work. Temp cooling: (1) 314-ton unit for RECEPTION, (1) 314-ton unit for CONFERENCE ROOM, (1) 112-ton temporary unit for MANAGER (used as temporary lounge space). To avoid electrical overload, temporary units should not be run simultaneously with new permanent units that serves the same space(s). User Requirements: Install FC-3 and FC-4 before demolition of existing FC-1. UCSD- FD&C Page 1 of 3

3 UCSD MEDICAL CENTER- HILLCREST iii. Phase 3 Scope of work: (E) FC-1 demo, EF-1 install, COPY ROOM work, SUPERVISOR work, MANAGER work, ANALYST work. Temp cooling: (1) 112-ton unit for SUPERVISOR, (1) 112-ton unit for MANAGER (used as temporary technical work space), (1) 112-ton unit for ANALYST. To avoid electrical overload, temporary units should not be run simultaneously with new permanent units that serves the same space(s). User Requirements: Complete all work for office spaces and restrooms before demolition of existing FC-1. One restroom at a time can be shutdown. iv. Phase 4 Scope of work: FC-1 install, TECHNICAL work, OPERA TORS work. Temp cooling: (3) 112-ton units for OPERA TORS. To avoid electrical overload, temporary units should not be run simultaneously with new permanent units that serves the same space(s). 2. Question: Can we hoist equipment and materials over the building, and if so what are the restrictions if any? Answer: Avoid hoisting equipment over the building. If this is too difficult, then alternate techniques can be discussed to minimize schedule disruptions. 3. Question: What are the working hours of each area? Answer: See item 1 above. 4. Question: It was mentioned on the walk that some of the racks that are currently in the way are to be removed at some point. For bidding purposes, can we assume that they will be gone? Answer: No racks will be removed. However, there will be another vendor hired separately by the owner that will be working inside of room 113 and possibly other rooms at the time of construction. The contractor will be required to coordinate work activity and allow access to the job site for this vendor. 5. Question: Does the BC Controller get insulated and does it need a condensate pan underneath it? Answer: BC-1 branch circuit controller comes factory-installed with insulation and secondary condensate removal. No additional insulation or condensate drip pan required on BC-1 unit. Insulation of refrigerant piping and condensate drain connected to BC-1 unit is still required. UCSD-FD&C Page 2 of 3

4 6. Question: For the split systems, can factory flexible ACR pre-insulated line-sets be used or does piping need to be rigid? Answer: Per manufacturer's instructions, 112H or H hard copper refrigerant gas and liquid piping with brazed connections is required between the outdoor condensing unit and branch circuit controller. Type 0 soft copper prefabricated linesets with flared connections are permissible between branch circuit controller and indoor fan-coil units. See attached PDF. UCSD- FD&C Page 3 of 3

5 9. Refrigerant piping installation The pipe is connected via a tenninal-branch type connecuon in which refrigerant piping from the outdoor un~ is branched at the tenninal and is connected to each of the indoor units The method of pipe connection Is as follows: flare connection for the indoor units, low-pressure pipes and high-pressure pipes for outdoor units, brazed connection. Note that the branched sections are brazed ~Warning: Do not use refrigerant other than the type Indicated In the manuals provided with the unit and on the nameplate. - Doing so may cause the unh or pipes to burst, or resuh in explosion or fire during use, during repair, or at the Ume of disposal of the uml. - It may also be In violauon of applicable laws. - MITSUBISHI ELECTRIC CORPORATION cannot be held responsible for malfunctions or accidents resulting from the use of the wrong type of refrigerant. Always use extreme care to prevent the refrigerant gas from leaking while using fire or flame. If the refrigerant gas comes In to contact with a flame from any source, such as a gas stove, It breaks down and generates a poisonous gas which can cause gas poisoning. Never weld In an unventilated room. Always conduct an Inspection for gas leakage after Installation of the refrigerant piping has been completed Caution This unit uses refrigerant R41 DA. Follow the local regulations on materials and pipe thickness when selecting pipes. (Refer to the table on the below.) I 1 ' Use the following materials for refrigeration piping Material: Use copper alloy seamless pipes made of phosphorus deoxidized copper. Ensure the Inner and outer surfaces of the pipes are clean and free from hazardous sulfur, oxide. dusts, shaving particles. oils, and moisture (contamination) Size: Refer to Hem 9.2 for detailed lnfonnation on refrigerant piping system. ~ Always observe the restrictions on the refrigerant piping (such as rated length, height difference, and piping diameter) to prevent equipment failure or a dedlne in heaung/cooling perfonnance. I~ Do not Install outdoor unit piping when It Is raining. 4 Commercially available piping often contains dust and other materials Always blow it dean with a dry inert gas. ~ t Use care to prevent dust. water or other contaminants from entering the piping dur1ng Reduce the number of bending portions as much as possible, and make bending radius as big as possible. tv For Indoor and outdoor branching and merging section, be sure to use the following twinning pipe sets and merge pipe sets (sold separately). Indoor TwiMing Pipe Kit model Line branch Lower stream unh model Less than 3D In total CMY-Y1D2SS-G2 Indoor Junction Pipe Kit model Total indoor model P36- P96 CMY-R16DC-J Outdoor Twinning Kit model Total outdoor model Total outdoor model P144YSKMU, P216 - P288TIYSKMU P168, P192T/YSKMU CMY R 1 OOCBK2 CMY-R1DDXLCBK Copper pipe size and radial thickness for R41 DA CITY MULTI Size(mm) Size (Inch) Radial thickness Radial thickness (mm) (mil) Pipe type a6.35 a1/4" DB 32 Type-0 a9.52 a3/b" D.8 32 Type-0 a12 7 a1/2" DB 32 Type-0 a15 88 as/8" 10 4D Type-0 "a19.d5 a3/4" 12 4B Type-0 'a19.d5 a3/4" 1 D 4D Type-1/2H or H a22.2 a7/8" 1 D 4D Type-1/2H or H a25.4 a1 " 1 D 4D Type-112H or H 1112B /8" 1 D 4D Type-112H or H /4" Type-112H or H /8' 12 4B Type-1/2H or H " Type- 1/2H or H that of a branching pipe, (i!,. Braze only with non-oxide brazing material for piping. Failure to do so may damage the compressor. Be sure to perform the non-oxidation brazing with a nitrogen purge. Do not use any commercially available anti-oxidizing agent since It may cause pipe corrosion and degrading of the refrigerant oil. Please contact Mltsublshl Electric for more details. (Refer to item 1D.2. for details of the piping connection and valve operation) (j_ii Always Insulate the piping properly. Insufficient Insulation will resuh In a decline in heating/cooling perfonnance. water drops from condensation fanning and other such problems (Refer to Hem 1 D.4 for thennal insulauon of refrigerant When connecting the refrigerant piping. make sure the valve ofthe outdoor unh Is completely dosed (the factory sehing) Do not operate ft unuithe refrigerant piping for the outdoor, indoor unfts and BC controller has been connected, a refrigerant leakage test has been perfonned, and the evacuation process has been completed. ii Never use refrigerant to perform an air purge. Always evacuate using a vacuum pump 13 Be sure to charge the system using liquid refrigerant 1'1.' Either a lack or an excess of refrigerant causes the unit to make an emergency stop Charge the system with an appropriate amount of refrigerant. When servicing, always check the notes concerning pipe length and amount of additional refrigerant at both locations, tha refrigerant volume calculation table on the back of the service panel and the additional refrigerant section on the labels for the combined number of indoor units (Refer to Item 9.2. for detailed lnfonnation on refrigerant piping system) ~Warning: When Installing and moving the unit, do not charge the system with any other refrigarant other than the refrigerant specified on the unit Mixing of a different refrigerant, air. etc. may cause the refrigerant cyde to malfunction and may result in severe damage. ~Caution: Use a vacuum pump with a reverse flow check valve. - If the vacuum pump does not have a reverse flow check valve, the vacuum pump oil may flow back into the refrigerant cyde and cause deteriorauon of the refrigerant oil Do not use the tools shown below used with conventional refrigerant. (Gauge manifold, charge hose, gas leak detector, check valve, refrigerant charge base, vacuum gauge, refrigerant recovery equipment) - Mixing of convenuonal refrigerant and refrigerant oil may cause the refrigerant oil to deteriorate.. Mixing of water will cause the refrigerant oil to deteriorate.. R41DA refrigerant does not contain any chlorine. Therefore. gas leak detectors for conventional refrigerants will not react to it. Manage the tools used for R410A more carefully than normal.. If dust, dirt, or water gets in the refrigerant cycle, the refrigerant oil will deteriorate. Never use exlsung refrigerant piping. The large amount of chlorine in convenuonal refrigerant and refrigerant oil in the existing piping will cause the new refrigerant to deteriorate Store the piping to be used during Installation Indoors and keep both ends of the piping sealed until just before brazing.. If dust, dirt. or water gets Into the refrigerant cyde. the oil will deteriorate and the compressor may feil Do not use a charging cylinder Using a charging cylinder may cause the refrigerant to deteriorate. Do not use special detergents for washing piping. Both pipe types can be used for pipe size D5 (3/4 inch) for R41DA air -(a Use an adapter If a specified refrigerant pipe has a different diameter from I - I