Weil-McLain Gold CGa 3b

Boiler Manual

Part Number 550-110-593/1099 17

Expansion tank

Diaphragm-type or bladder-type

expansion tank — Figure 9

1. Ensure expansion tank size will handle boiler and

system water volume and temperature. Tank must

be located in boiler return piping as close to boiler

as possible, before inlet side of circulator. See tank

manufacturer’s instructions for details.

2. Install an automatic air vent as shown.

Closed-type expansion tank — Figure 10

1. Ensure expansion tank size will handle boiler and

system water volume and temperature. See tank

manufacturer’s instructions for details.

2. Connect tank to ½" NPT tapping located behind

supply outlet, using ½" NPT piping. Pitch any

horizontal piping up towards tank 1 inch per 5 feet

of piping.

Use Figure 9 or Figure 10only for single-zone systems designed for return water at least 130 °F.

For systems with low return water temperature possible, such as converted gravity systems and

radiant heating systems, refer to the special piping suggestions of pages 20-25. Failure to prevent

low return water temperature to the boiler could cause corrosion of the boiler sections or

burners, resulting in severe personal injury, death or substantial property damage.

Undersized expansion tanks cause system water to be lost from relief valve and makeup water

to be added through fill valve. Eventual section failure can result.

Water piping — single-zone system

Figure 9

Diaphragm- or bladder-type expansion tank

Piping to single-zone system using

diaphragm-type or bladder-type expansion

tank. See Table 3 for piping sizes.

Figure 10 Closed-type expansion tank

Piping to single-zone system using closed-

type expansion tank. See Table 3 for piping

sizes.

59306

CGa

GOLD

From

system

Cold

water

fill

To DIAPHRAGM

expansion tank

and fittings

Isolation

valve Isolation

valve

To system

Circulator*

Circulator

Drain

valve

Relief

valve

Automatic

air vent

*Alternate

location

3b

59307

To system

From

system

Isolation

valve

Drain

valve

Relief

valve Circulator*

Isolation

valve

Circulator

Cold water fill

CLOSED-type

expansion tank

*Alternate

location

CGa

GOLD

Contents

Main Please read before proceeding When servicing boiler Boiler operation Boiler water Installer Page How it works . . . Other boiler components: Boiler circulator Contents Hazard definitions Prepare boiler location codes & checklist 1a Installations must follow these codes: Before locating the boiler, check the following: Prepare boiler location clearances1b Service clearances Flooring and foundation Residential garage installation Small space installations Prepare boiler location vent system1c When removing boiler from existing common vent system: Chimney or vent requirements Prepare boiler location air contamination 1d Air from inside building Prepare boiler location air openings1c Special considerations Tight construction Prepare boiler placement and setup 2a Inspect orifices and burners Place boiler/crate near position Orifice replacement procedure 2b Prepare boiler pressure test Perform hydrostatic pressure test Page Prepare boiler vent damper installation Water piping general information3a General piping information Relief valve System water piping Pressure/temperature gauge 3b Water piping multiple zones Typical piping multiple-zone installations 3d Primary/secondary (preferred) bypass piping method Temperature gauges Primary/secondary (preferred) piping for radiant heating or converted gravity systems 3e Temperature gauges Boiler-bypass piping method Boiler-bypass (alternate) piping for radiant heating or converted gravity systems 3f System-bypass piping method System-bypass piping for converted gravity (or steam) systems 9 3g Gas piping Field wiring Electrical installation must comply with: Wiring connections Start-up preparation6a Determine if water treatment is needed Check for gas leaks Fill the system with water Inspect system water piping Start-up operate boiler6b Start-up preparation continued6a Inspect base insulation Start the boiler Start-up if boiler doesnt start . . .6c Check for: Start-up operate boiler continued6b Check system and boiler Start-up Check-out procedure checklist7 Installation and service certificate 34 Operation Standing Pilot CGa Lighting instructions CGa-25 to CGa-88b FOR YOUR SAFETY READ BEFORE LIGHTING LIGHTING INSTRUCTIONS FOR YOUR SAFETY READ BEFORE LIGHTING LIGHTING INSTRUCTIONS Lighting instructions CGa-25 to CGa-88b Natural gas Standing pilot Gas valve manufacturer Robertshaw Gas valve model(s) 7200 Figure 24 Ignition control module sequence of operation status light indications Operation Figure 25b Ladder wiring diagram Spark-ignited pilot system MV FLAME LIMIT DAMPER Legend for ladder wiring diagram Page Operating instructions CGa-25 to CGa-69b Natural gas Spark pilot Gas valve manufacturer Robertshaw Gas valve model(s) 7200 Page Page 44 Service and maintenance Table 6 Service and maintenance schedules (service technician and user) ANNNUAL START-UP Service technician Owner maintenance Service & maintenance annual start-up10b Reported problems Boiler area Air openings Flue gas vent system Service & maint. annual start-up continued10b Oiled-bearing circulators Boiler heating surfaces Burners and base Gas piping Service & maint. annual start-up continued10b Before troubleshooting: Troubleshooting procedure11a Page Chart 1 Standing pilot Boiler will not fire Troubleshooting standing pilot boilers11b Control indicator lights non-lockout modes Troubleshooting the control module Control indicator lights lockout modes Part Number 550-110-593/1099 53 Figure 30 Control module connections DAMPER LIMIT TSTAT CIRC Indicator lights Chart 2 Spark-ignited pilot Troubleshooting POWER light status Is POWER light... Chart 3 Spark-ignited pilot TSTAT CIRC & POWER lights flashing Did you find a voltage across the two external thermostat circuit wires? and Do the lights still flash? Chart 4 Spark-ignited pilot DAMPERlight flashing Chart 5 Spark-ignited pilot FLAME & POWER lights flashing Is pilot burning? Do Are lights flashing? Is gas present at gas valve inlet and within above range? Figure 30, item 8, page 53 Does light flash now? Is 24 VAC present there? Is gas present at gas valve inlet and within above range? Chart 7 Spark-ignited pilot Insufficient heat or no heat (POWERlight on steady) Is thermostat circuit closed (continuity across wires)? Is vent or combustion air piping free of blockage? Are limit switch contacts closed? Figure 30, Item 7, page 53 Replacement parts12a Page Page Page Page Page 66 Dimensions13a Figure 36 Dimensional drawing ALL DIMENSIONS IN INCHES Ratings13b 1 Table 7 Ignition system model suffixes Notes DOE