Roberts Gorden UHA[X][S] 125, UHA[X][S] 45, UHA[X][S] 30 TROUBLESHOOTING 13.1 General, Start

UHA LOW PROFILE UNIT HEATER INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 13: TROUBLESHOOTING 13.1 General

START

Are gas & electrical	No	Turn on supplies.
supplies on?

WARNING

Explosion Hazard

Installation, service and annual inspection must be done by a contractor qualified in the installation and service of gas-fired heating equipment or your gas supplier.

Turn off gas and electrical supplies before performing service or maintenance.

Failure to follow these instructions can result in death, injury or property damage.

Yes

Is ignition control showing a

"4 flashes" LED code?

Noo

Is ignition control showing a

"2 flashes" LED code?

No

Does the flue

blower run?

	UHA 30 - 75: Press in reset
	button on manual reset limit
	switch. UHA 100 - 125: Wait
Yes	10 - 15 minutes for limit Yes
	switch to cool. Does fan
	stop running?
	No
	Replace temperature
	limit switch.
	Burner has locked out due
Yes	to ignition failure. Use
	Troubleshooting for
	Automatic Ignition Burner
	Systems section to test
	burner.
No	Use Troubleshooting for
	Flue Blower section to test
	fan.

Fan and limit switch are operating normally.

Yess

With external controls (i.e.		Has burner “Locked Out”? No
thermostat) on, does the No
burner continue through the
heating cycle?
		Yes
		Use Troubleshooting for
		Automatic Ignition Burner
		Systems section to test burner.
Yes
Heater Operating		If problems persist, contact
	No	Roberts-Gordon LLC at
TROUBLESHOOT ENDS.		www.rg-inc.com

The limit switch has
tripped. See Manual Reset No	Replace limit switch.
Limit Switch Figure.

Yes

Ensure proper air flow clearance for axial fan. Open louvers slightly.

Replace axial fan if it does

not operate.

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