A-8-01 Typical questions and answers on the boiler specifications on tender and boiler contract documents

Transcription

1 Boiler specifications A-8-01 Typical questions and answers on the boiler specifications on tender and boiler contract documents Burner General: Q. Burner and burner safeguards shall comply with the CGA Gas codes. A. Our boiler controller (flame safety and water level control) comply with UL and c-ul. Q. Burner control devices and control sequence shall comply with the requirements of Factory Mutual. A. Yes. Request on PO. Q. The turndown ratio for the burner shall be at least 4:1 A. No, our turn down ratio is usually 2:1 for EX and depends on model for LX. Refer to A-1 for details. Oil burner: Q. Oil burners shall be: - pressure atomizing forced draft type. A. yes Q. Oil burners shall be complete with -Built-in blower to supply combustion air, complete with motor, silencer and damper A. yes except the silencer(need details of what they need). Silencer is optional. Q. -with stainless steel flame retention diffuser A. Yes Q. - Oil pump complete with integral relief valve A. oil pump has internal recirculation or external return to the tank (depends on model) Q. -Oil filter A. yes, it comes as standard Q. - Pressure gauge A. yes, gauge is standard on the pressure side of the pump. Q. -High voltage ignition transformer A. yes only for EX(H)(W)-100. Other models have gas pilot as ignition means. Q. - Flame observation port A. yes, it comes as standard. Q. - Easy access to nozzles and electrodes A. yes, we can say that. Q. - Fuel and air modulating controls for maximum burner efficiency throughout operating range A. No, our burner is off-low-high step fire control. Q. -Oil atomizer utilizing air blower A. No, our oil atomizer uses the oil pressure itself to spray the oil, and mixes with air supplied by the blower. 1 / 5

2 Q. - electric oil heater to heat fuel oil from - 48 C to 0 C A. No, our burner is designed for #2 fuel oil, which does not need the heater for proper combustion. In cold region or season, the oil supplier usually provides #2 oil arranged for use in cold conditions. Gas burner Q.the burner shall be complete with gas train including -lubricated type manual shut off cock on the gas train A. No, our gas train has ball type manual shut off valve. Q. -automatic gas vent valve A. automatic gas vent is not standard for boilers 200BHP and below. 250 and 300BHP boilers have that, but it is not required by code we comply with. Q. -Main gas safety shutoff valves A. Yes, we have two safety shutoff valves (both UL listed as safety shutoff valve) Q. -high and low gas pressure switches A. Yes, our boiler has both high and low gas pressure switches as standard. Q. -Main manual gas shutoff and leakage test cocks A. Main manual gas shutoff valve is standard, and leakage test cocks are optional as CDS-1 option. Q. -gas pressure regulators A. Standard. Except for LX50-07 which has the gas regulating function integrated in the valve. Q. -Air safety switch A. Air pressure switch is standard Q. -Electronic annunciating combustion safety control with UV sensor. A. Our BL combustion safety control includes display and lamps for status and errors. Q. -Automatic gas valve A. main and pilot gas valves are automatic Q. -Adjustable cam gas metering valves. A. No, we can monitor gas flow using gas orifice differential pressure. Pilot burner Q. -gas pressure regulators A. Standard Q. -Pilot solenoid valve and shutoff cock A. Yes, the pilot gas train has 2 safety shutoff valves and manual shutoff cock. Q. -gas pilot assembly and ignition transformer A. Yes, but except EX(H)(W)100-O. for 100BHP oil burner, the burner is spark direct ignition. 2 / 5

3 Boiler Q. Boiler pressure vessel shall conform to ASME section. A. Our boiler pressure vessel has S stamp = ASME section or H stamp = ASME Section IV. Q. ASHRAE/IESNA 90.1 Compliance: Water-tube boilers shall have minimum efficiency according to Table A. Our boiler efficiency conform to such minimum efficiency requirement. Q. Design, documentation, fabrication and testing shall comply with ASTM, ANSI, CGA, ULC standards and TSSA requirements. A. CGA / CSA = boilers are no longer labeled with these approvals because they are equivalent to UL/c-UL, ULC = boilers will be either labeled UL and c-ul, and not ULC. Q. boiler water tubes shall be made of ASME SA-106-B. A. Now, main models uses SA-178-A, and some still uses SA- 106-B. Q. Boiler should include the following trim: -NEMA 250 type 1 control box A. Our boiler is a packaged boiler including the boiler control panel, and the entire boiler is UL listed. In this case, the NEMA control box is generally not required. Our control box is following the strict rules in the UL codes. Q. -Steam pressure gauge with 6 dial: A. We do have one pressure gauge but 4. And also pressure display on the controller. Q. -Pressure control operator.(modulating) A. Yes, we have BL(or XJ-1) pressure control as well as the backup pressure control switch from Honeywell as standard. However, it is not modulating as itself. Q. -Pressure high limit safety control. A. Yes, we have high limit safety switch as standard. Q. -Water gauge glass A. No, our boiler type is exempt from gauge glass requirement in the ASME code. Q. -Low-Water Cutoff Switch: Manual reset type. External column mounted float type. A. We have the low water cutoff as standard (code requirement) = manual reset, external column mounted, but electrode type (not float type) Q. -Auxiliary low water cutoff A. Yes, we have it as standard = auto reset. Q. -feed pump control A. Yes, we have it as standard included in the BL(or XJ-1). Q. -ASME safety valve(s) A. Yes, we have 1 or 2 (quantity depends on ASME requirement and design) safety valve(s) on the boiler pressure vessel as standard. Q. -Auxiliary contacts for start/stop and alarm indication A. we can supply some dry contacts for monitoring purpose Q. -Alarm Bell: Factory mounted on control panel with silence switch. 3 / 5

4 A. yes Q. -Provide electronic programming relay, feedwater pump and blower motor starter control switches, control circuit transformer and alarm bell. A. all included. Q. -selector switch to permit only low fire. A. not included for BL boilers. Low fire hold only in the test mode. Q. Jacket: Sheet metal, with screw-fastened closures and baked-enamel protective finish. A. Our boiler is installed with painted sheet metal casings. (not baked paint) Q. Mounting base to secure boiler to concrete base A. Yes Q. Two bottom blow valves (one slow and one quick opening, or two slow opening) A. standard boiler includes one quick or slow opening valve. One additional slow opening valve is optional. Economizer Q. Provide an economizer for each of the steam boilers. The economizers shall be gas to liquid heat exchangers, designed to utilize heat in the boiler flue gasses to preheat boiler feedwater. A. Yes. Q. Tube material shall be SA-178-A boiler tube A. economizer water tubes are all SA-106-B boiler tube. Tube size is 1 SCH40. Q. Provide economizer with safety valve. A. on boilers for US market, the economizer is made under ASME section 1 and it is part of the boiler. The safety valve on the main pressure vessel protects the economizer from excessive pressure. On some boilers for Canadian market, the economizer is made under ASME section 8, and considered as a separate pressure vessel. In this case, the economizer is equipped with a pressure relief valve. Q. Provide economizer with automatic soot blower A. Our boiler is intended for fuel gas and #2 oil and the deposit of soot is relatively small. That is why we do not need the soot blower. In case of economizer cleaning, we can open the box and clean the vessels easily for EX models. Q. Provide additional feed water controls as required to ensure proper economizer operation. A. Economizer feed water control is combined with the boiler water control (feed water to the boiler = feed water to the economizer). With BL control, we have one additional control to prevent the water to boil in the economizer. 4 / 5

5 Ancillary Q. Boiler shall use propane as a backup fuel. A. Propane backup fuel is optional only for some LX models. Q. Barometric Damper: Galvanized-steel assembly with flue-gas thermometer having a minimum 90 mm diameter dial. A. Barometric damper is not supplied by our factory. Consult chimney installer when required. Q. Silencer to reduce the noise to 80dB or below A. Air inlet silencer is optional. It can reduce the noise from 85dB to 80dB. Revision Record: Rev. Date Content of change Related docs Revised by 00 May 2009 New content T.F. 01 Apr Amendments to section Boiler K.S. 5 / 5