Roberts Gorden NEMA 4 Troubleshooting Flow Chart continued, Ignition Module Diagnostic Codes

					Contact your
					ROBERTS GORDON®
					Independent Distributor.
	Yes				Yes
	Are pump and/or burners				Are shield wires from RS-485
				Yes	communication wiring and	Verify wiring between
	turning on and off erratically?				VFD 0-10 V signal wiring
						controller and burner.
					correctly twisted and/or
Yes	No				grounded?
						No
After 45 seconds pre-purge			On the relay board, is the			Is there power at the
		No		appropriate zone relay Yes			Yes
period, do the burners light?						burner recepticle?
					(#1-3) LED lit?

Replace plug-in relay. See

Replacement Parts section.

Correct gas problem. See

gas piping section of

CORAYVAC® IOS manual

(P/N 127102NA)

No

Yes Is there proper gas pressure and flow to the burners?

Yes

Troubleshooting Flow Chart (continued)

No

Is there continuity across meter input #4 (pressure switch input) on the control board?

No

	Yes
Is there 24 Vac across the	Is there 24 Vac across the
Yes control board 24 V output Yes	relay board's appropriate 24
(#1-3) for that zone?	V output connection (#1-3)?
No	No

Unplug burner, wait 10		Check for proper vacuum
seconds, then plug it in again.
	Yes	at end vent. See
Does the ignition module		Commissioning of the
begin ignition		CRV System for details.
sequence by sparking?
No

Yes

Verify pressure switch wiring

and operation. Replace

pressure switch if necessary.

Contact your		Secure wiring between 24 V
ROBERTS GORDON	®	output on the control board

Independent Distributor.	and output connection on
	the relay board.
Adjust system for proper

Pre-purge. Wait 45 seconds.

Do the burners light?

Check LED on module and refer to LED codes below.

No

Yes Troubleshoot Ends

Do all the burners	No	Is the end vent vacuum
ignite smoothly?		setting too high?
Yes		No
		Wrong end vent plate may
		be installed. Make sure
		plate and burner match.

Yes	vacuum at the end vent.
	See Commissioning of the
	CRV System for details.

Is there 24 V at the burner

transformer secondary (blue and yellow wires)?

No

Replace burner transformer.

Yes Replace ignition module.

		Ignition Module Diagnostic Codes:
	LED	Problem	Solution
	4 second steady
	flash at start of cycle	Normal	Wait for valve to open
Yes	Steady on	Microprocessor failure	Replace module
		within module
	Three flashes	Ignition lockout	Recycle unit: check for
		Lockout of module	spark and valve opening and
		after 3 tries	replace:if none, replace module

39

SECTION 9: TROUBLESHOOTING