GOLD CGi-4E Gas-Fired Water Boiler — Boiler Manual

11a Troubleshooting — general

Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation.

Never jumper (bypass) rollout thermal fuse ele- ment or any other device except for momentary testing as outlined in Troubleshooting Charts. Severe personal injury, death or substantial

property damage can result.

Before troubleshooting:

1.Have the following items:

a.Voltmeter that can check 120 VAC and 24 VAC.

b.Microammeter with a minimum scale range of 0-25.

c.Continuity checker.

d.U-tube manometer.

2.Check for 120 VAC (minimum 102 VAC to maximum 132 VAC) to boiler.

3.Make sure thermostat is calling for heat and contacts (including appro- priate zone controls) are closed. Check for 24 VAC between thermostat wire nuts and ground.

Check the following:

1.Wire connectors to control module are securely plugged in at module and originating control.

2.Air pressure switch hoses are properly and securely plugged in and are not damaged.

3.Verify gas supply pressure:

a.With boiler OFF — 13” w.c. maximum natural or propane gas pressure upstream of gas valve.

b.With boiler ON — Upstream: 5” w.c. minimum natural gas pres- sure or 11” w.c. propane gas pressure upstream of gas valve.

4.Verify gas manifold pressure (downstream of gas valve):

a.Natural gas:

Manifold pressure, high fire: 3.50” w.c.

Manifold pressure, low fire: 0.90” w.c. while in low fire at start-up (60 seconds)

b.Propane gas:

Manifold pressure, high fire: 10.0” w.c.

Manifold pressure, low fire: 3.50” w.c. while in low fire at start-up (60 seconds)

c.If necessary, adjust gas pressure on the gas valve as shown below. After adjustments, refer to page 35 to check the flame.

High-fire gas pressure adjustment

Low-fire gas pressure adjustment

Honeywell VR8204Q two-stage gas valve

48

Air pressure switch

Make sure boiler water temperature is 100 °F or cooler before starting proce- dure to obtain appropriate readings.

The boiler will not operate correctly un- less pressure switch hoses are correctly located. The red hose connects from the right side (negative) hose barb to the flue collector. The white hose con- nects from the left side (positive) hose barb of the switch to the connector box (between flue collector and inducer) as shown in Figure 36, page 49.

Check pressure switch setting

1.See Figure 36, page 49, and Table 9.

2.Remove both air pressure switch hoses from air pressure switch.

3.Install tees and tubing as shown in Figure 36, page 49, to inclined manometer.

4.Turn off gas valve and set thermostat to call for heat. Inducer will run but burners will not ignite.

5.Check for 24 VAC between both air pressure switch termi- nals.

Troubleshooting air pressure reading

1.If manometer reading is lower than the setpoint of the switch (see Table 9) — check for possible causes:

•blockage in hoses

•obstruction in inducer housing outlet

•loose inducer wheel on motor shaft

•inducer motor not in proper rpm

•inducer back plate not sealed properly

•blockage in block assembly

•blockage in flue pipe or termination

•incorrect pressure switch

6.If manometer reading is above the setpoint of the switch (see

Table 9), but there is not 24 VAC between both air pressure switch terminals — replace air pressure switch.

Return to normal operation

When pressure reading is correct and air pressure switch is oper- ating properly — remove tees and reinstall hoses to air pressure switch.

Table 9 Pressure switch setpoint (for elevations above 2,000 ft, contact your local Weil- McLain sales office for details.)

Boiler model number

Inches W.C.

 

 

CGi-4E

1.36

 

 

 

Part Number 550-110-711/1108

Page 47 Page 49
Page 48
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Weil-McLain CGI-4E manual 11a Troubleshooting general, Before troubleshooting, Check the following, Air pressure switch
Page 47 Page 49

CGI-4E specifications

The Weil-McLain CGI-4E is a standout in the realm of commercial boilers, designed to meet the rigorous demands of a variety of heating applications. This gas-fired cast iron boiler exemplifies durability, efficiency, and performance, making it a popular choice in various commercial settings, including schools, hospitals, and office buildings.

One of the main features of the CGI-4E is its cast iron construction. Cast iron has long been favored for its excellent heat retention and distribution capabilities, leading to improved overall efficiency. The boiler is designed to maximize heat output while minimizing energy consumption. This characteristic is especially beneficial for businesses seeking to lower their energy costs without sacrificing comfort.

In terms of efficiency, the Weil-McLain CGI-4E boasts an impressive thermal efficiency rating. Its design incorporates advanced technology, allowing it to achieve an AFUE rating of up to 84%. This efficiency is achieved through features such as a full-modulating burner and a unique heat exchanger design that allows for optimal heat transfer and reduced flue gas temperatures.

The CGI-4E is also remarkable for its versatility. It is offered in a variety of sizes, making it suitable for different heating loads. This flexibility allows for installation in a wide range of environments, adapting easily to both existing and new heating systems. Additionally, the boiler comes with multiple venting options, including direct vent and conventional venting, further enhancing its installation flexibility.

Another standout feature is the integrated boiler control system, which simplifies operation and monitoring. This control system optimizes burner performance and enhances safety features, including automatic shut-off in case of system anomalies. The advanced controls also allow for easy integration with building management systems, enabling better energy management and reduced operational costs.

The CGI-4E also emphasizes ease of maintenance, with service-friendly designs that allow technicians to access components without difficulty. This consideration translates to reduced downtime and lower maintenance costs, ensuring that the boiler operates efficiently over its lifetime.

Overall, the Weil-McLain CGI-4E blends reliability, efficiency, and advanced technology, making it a premier choice for commercial heating needs. Its cast iron construction, impressive efficiency ratings, versatile installation options, and user-friendly controls solidify its reputation as a leading boiler solution in the industry.
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