Weil-McLain 550-110-710/0107 manual 4a Water piping general information

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GOLD CGi Gas-Fired Water Boiler — Boiler Manual

4a Water piping — general information

General piping information

If installation is to comply with ASME or Canadian requirements, an ad- ditional high temperature limit is needed. Install control in supply piping between boiler and isolation valve. Set second control to minimum 20°F above setpoint of first control. Maximum allowable setpoint is 240°F. See Section 9b for wiring.

A low water cutoff device is required when boiler is installed above ra- diation level or by certain state or local codes or insurance companies. Use low water cutoff designed for water installations. Electrode probe-type is recommended. Purchase and install in tee in supply piping above boiler.

Use backflow check valve in cold water supply as required by local codes.

Circulator

The circulator is shipped loose (wiring pre-attached to boiler) to allow you to locate it either in the return or supply piping, as desired. See page 3 for a typical instal- lation. Pipe the expansion tank to the suction side of the circulator whenever possible. Install an air separator in the supply piping. Connect the expansion tank to the air separator only if the separator is on the suction side of the circulator. Always install the system fill connection at the same point as the expansion tank connection to the system. Figures 16 and 17 show typical near-boiler piping connections.

Pressure/temperature gauge

Install pressure/temperature gauge in tee on supply piping (as shown in drawing on page 3).

Relief valve

Install relief valve vertically in ¾” tapping on side of boiler. See Figure 16 or 17, page 21, and the tag attached to the relief valve for manufacturer’s instructions.

To avoid water damage or scalding due to relief valve operation:

•Discharge line must be connected to relief valve outlet and run to a safe place of disposal. Terminate the discharge line to eliminate possibility of severe burns should the valve discharge.

•Discharge line must be as short as possible and be the same size as the valve discharge connection throughout its entire length.

•Discharge line must pitch downward from the valve and terminate at least 6” above the floor drain where any discharge will be clearly visible.

•The discharge line shall terminate plain, not threaded, with a mate- rial serviceable for temperatures of 375°F or greater.

•Do not pipe the discharge to any place where freezing could occur.

•No shutoff valve shall be installed between the relief valve and boiler, or in the discharge line. Do not plug or place any obstruction in the discharge line.

•Failure to comply with the above guidelines could result in failure of the relief valve to operate, resulting in possibility of severe personal injury, death or substantial property damage.

•Test the operation of the valve after filling and pressurizing system by lifting the lever. Make sure the valve discharges freely. If the valve fails to operate correctly, replace it with a new relief valve.

System water piping

See Figure 16 (diaphragm-type or bladder-type expan- sion tank) or Figure 17 (closed-type expansion tank) and Table 6, for near-boiler and single-zone systems designed for return water at least 130°F.

See pages 22-23 to complete multiple-zone piping or pages 24-29 to complete piping for radiant heating systems or converted gravity systems (large-volume systems originally designed for circulation by natural convection rather than a pump). See page 29 for boilers used with refrigeration systems.

Table 6  Water pipe size (based on 20°F rise)

Boiler

To

From

model number

system

system

CGi-25

¾"

¾"

 

 

 

CGi-3, 4, 5

1"

1"

CGi-6, 7

1¼"

1¼"

 

 

 

CGi-8

1½"

1½"

 

 

 

Note: The boiler supply and return connections, the return/ drain tee and the supply/gauge tee supplied with the boiler are 1¼” NPT. One of the circulator flanges sup- plied with the boiler is 1¼”. The other circulator flange is the size of the recommended system piping shown above.

Chillers or air handling units:

Install boiler such that —

•Chilled medium, if used, is piped in parallel with heating boiler. Use appropriate valves to prevent chilled medium from entering boiler. Consult I=B=R Installation and Piping Guides.

•If boiler is connected to heating coils located in air handling units where they can be exposed to refrigerated air, use flow control valves or other au- tomatic means to prevent gravity circulation during cooling cycle. Circulation of cold water through the boiler could result in damage to the heat exchanger, causing possible severe personal injury, death or substantial property damage.

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Part Number 550-110-710/0107

 

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Contents Gold CGi How it works Gold CGi Gas-Fired Induced-Draft Water Boiler Contents Please read before proceeding Before locating the boiler, check the following 1a Prepare boiler location codes & checklistInstallations must follow these codes 1b Prepare boiler location clearances Chimney or vent require- ments When removing boiler from an existing common vent system1c Prepare boiler location vent system 1d Prepare boiler location air contamination Products to avoid1e Prepare boiler location air openings Air openings must be providedAir opening options Two openings Air supply from inside the buildingExhaust fans and air movers Motorized air dampersSingle air opening option Exception for large spaces2a Prepare boiler placement & setup Orifice replacement procedurePlace boiler/crate near position Inspect orifices and burners2b Prepare boiler pressure test Hydrostatic pressure testDrain and remove fittings Prepare boiler for test3a Venting general information Venting chimney draft ventingCGi venting methods Chimney draft or Direct exhaust Chimney draft venting3c Venting Direct exhaust components Obtain vent system components3d Venting direct exhaust vent starter Vent StaR-34 Vent starter3e Venting direct exhaust termination Vent termination minimum clearancesSidewall venting See Figures 14 3f Venting direct exhaust installationVertical venting See . Follow vent Using any termination other than one of those shown 4a Water piping general information Closed-type expansion tank 4b Water piping single-zone systemDiaphragm-type or bladder- type expansion tank Figure 4c Water piping multiple zones Piping multiple zonesZoning with circulators 4d Piping low temperature systems Temperature gaugesValve adjustment Primary/secondary preferred bypass piping methodPrimary/secondary piping Valve adjustment BOILER-bypass piping methodBoiler-bypass piping Zoning with SYSTEM-bypass piping method 4e Water piping refrigeration system Prevent chilled water from entering boilerConnecting gas supply piping to boiler Gas pipingNatural Gas Propane GasField wiring Electrical installation must comply withWiring connections ThermostatFreeze protection when used 7a Start-up preparationCheck for gas leaks Determine if water treatment is neededDo not use petroleum-based cleaning or sealing compounds Fill the system with waterInspect system water piping Inspect base insulationCheck system and boiler 7b Start-up operate boilerStart the boiler 7c Start-up if boiler doesn’t start Check burner flamesCheck for Pilot burner flame FigureCheck-out procedure checklist Thermostats9a Operation sequence During main burner operation9b Operation wiring diagrams Schematic wiring diagramLadder wiring diagram 9c Operating instructions CGi-25 to CGi-6 9c Operating instructions CGi-25 to CGi-6 9c Operating instructions CGi-25 to CGi-8 10a Service and maintenance schedule Verify Proper Operation After Servicing10b Service and maintenance annual start-up 10b Service & maintenance annual start-up Burners and baseCondensate drain system Inducer motorGas piping Cold fill and operating pressuresAir vents and air elimination Limit controls and cutoffsReview the User’s Information Manual with the owner Review with ownerBoiler relief valve 11a Troubleshooting procedure 11b Troubleshooting componentsBefore troubleshooting Air pressure switchControl indicator lights Troubleshooting the control moduleControl indicator lights Lockout modes Control moduleControl module connections 11c Troubleshooting control module lights Chart Light flashingRemove 120 VAC in plug , Item 3, page 50 on control module VAC in plugChart 2 Tstat Circ & Power lights flashing Chart 3 Press Switch & Power lights flashing Chart 4 Flame & Power lights flashing Usually indicates flame sensed when it shouldnt be thereDoes blower motor operate? Item 8 , Verify Sequence Operation, FigureControls Repair Parts Lists 12a Replacement partsSection assembly Base Jacket Trim Controls 12b Replacement parts section assembly Section assembly12c Replacement parts base Base assemblyDescription Weil-McLain Part number 12d Replacement parts jacket Jacket assemblyBoiler Model Weil-McLain part number BoilerModel Weil-McLain part number 12e Replacement parts trim Fittings shown are included with boiler12f Replacement parts controls Propane gas components13a Dimensions Dimensional drawing13b Ratings Handling ceramic fiber and fiberglass materials Removal of Combustion Chamber Lining or Base Panels
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