Weil-McLain GOLD CGS-4E - Manual (Page 43)

Part number 550-110-282/1108
43
GOLD CGs-4E Gas-Fired Water Boiler — Boiler Manual
Troubleshooting — procedure
11a
Label all wires prior to disconnection when servicing controls. Wiring
errors can cause improper and dangerous operation.
Never jumper (bypass) rollout thermal fuse element 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 appropriate 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 pressure 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 29 to check the flame.
High-fire gas pressure adjustment
Low-fire gas pressure adjustment
Honeywell VR8204Q two-stage gas valve