Weil-McLain CGS-4E manual Verify Sequence of operation

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

11d Troubleshooting — control module lights (cont.)

CHART 7 — Insufficient heat or no heat to system (POWER light on steady)

Electrical shock hazard — Wherever you see TURN OFF POWER, follow the instructions. Failure to follow instructions could result in severe personal injury, death or substantial property damage.

• Has it been at least 5 minutes since setting thermostat to call for heat? If not, wait 5 minutes. Is system heating?

• Is thermostat set to call for heat? Remove thermostat wires at boiler and check continuity across the two wires. If circuit isn't closed, check external thermostat (zone valve, relay, etc.) wiring. Correct problems and retry.

• Reconnect external thermostat wiring at boiler.

Is thermostat circuit closed (continuity across wires)?

No Yes

Is boiler System circulator operating?

No Yes

•Remove CIRCULATOR harness plug from CIRCULATOR plug receptacle (Figure 25, Item 7, page 46). Check with voltmeter across pins of control module receptacle.

Does voltmeter show 120 VAC across pins?

No Yes

Are all red lights off?

No Yes

Wait 30 seconds. Are all red lights off?

No Yes

Replace control module. Retest.

•Boiler is in standby.

•Set thermostat to call for heat and recheck

operation.

•Verify Sequence of operation, Figure 18, page 33.

•	Replace control	•	Repair/replace
	module.		circulator. Retest.
•	Retest.	•	Repair/replace
			wiring. Retest.

• Wait 5 minutes.

• If you have sufficient heat — boiler should be in normal

operating sequence. (See normal sequence of operation, Figure 18, page 33.)

• If you have less than sufficient heat —

Are vent and combustion air piping free of blockage?

No Yes

	Is FLAME light on?
Yes	No
	Is LIMIT light on?
No	Yes

•	Correct conditions and	Is manifold pressure:
	recheck operation.		3.50" w.c. on natural gas?
• See Figure 18, page 33			10.0" w.c. on propane?
	for normal sequence of		Yes		No
	operation.
• Check heat loss calculation
	versus boiler size.
•	Clock gas input.			• Replace timer relay.

•Wait for boiler water to cool to temperature 20 to 30 °F lower than temperature set on limit switch.

Are limit switch contacts closed?

•	Check limit switch			•	Replace control module.
	contacts with continuity			•	Retest.
	checker.
	Are limit switch contacts
		closed?
						Check rollout switch
	No		Yes
					continuity — is switch
							closed?
						No		Yes
•	Replace rollout switch.

No

•Replace limit switch.

•Retest.

Yes

•

Figure 18, page 33

•Also check setting on limit switch (should be above 140°F.).

If rollout thermal fuse element has	•	Check any other
		limit controls wired
opened, determine cause and		into the limit
correct condition. Failure to do so		circuit. If all are
will cause severe personal injury,		OK, then replace
death or substantial property		control module.
damage.	•	Retest.

Part number 550-110-282/1108

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