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View Full Version : Heater wont stay on!


Lou Placentia
01-14-2013, 01:24 PM
When turning the thermostat on heat, the fan turns on and air comes out of the fvents. It's not warm air, but it's air. It never heats up and after about 5 minutes it turns off and doesn't turn on again until you turn the switch off and then back on the thermostat. Is there a pilot light I'm missing? There is propane, all of the appliances light up just fine.

Thanks in advance for your help!!!

MrE
01-14-2013, 02:38 PM
Lou, here is a link to a thread discussing a similar issue. There is also a link in the thread to the owners manual. http://www.luxurycoachlifestyle.com/forum/hvac/4022-no-heat-suburban-furnace.html

The Newell
01-14-2013, 06:50 PM
It sounds to me like a critter problem. Maybe dirt dobbers. It could be them, or spiders making nests in your burner or vents. If you get close to the heater unit, can you hear a "clicking" sound (the ignitor trying to light the burner)? If so, and it does not light, critters somewhere would be my diagnosis.

PIExpress
01-14-2013, 11:49 PM
Your furnace is not igniting. The fans come on first, but if no ignition occurs they will eventually shut off, as yours do. Ignition is electronic, not by pilot light. Low voltage to the furnace could be the cause

NewellCrazy
01-15-2013, 04:31 PM
There are several possible issues

Here is the sequence of events that SHOULD happen

Thermostat calls for heat, Blower turns on and air begins to move,
As the air moves a SAIL SWITCH inside the furnace senses air flow and closes
Burner lights and air gets warm... As rig heats up Thermostat signals "Hot enough" and burner shuts down
Fan may continue to run for a few seconds or may shut down promptly

Possible issues are MOSTLY with the air flow.. If something has "nested" in an air duct, air flow will be reduced. If you have a throw rug or other object blocking more than one air vent, air flow may be reduced, if there is "Crud" build up in the ducts, air flow may be reduced, if a duct has collapsed,, Air flow may be reduced

If the batteries are low, the blower can not come up to speed and air flow is reduced

if the blower is worn out.. Likewise

If air flow is reduced the sail switch won't sail closed and thus the burner won't light

To test.. You need to check the state of the sail switch.. I am afraid I can not help much there as I've never actually looked at the control board for my heater.

Next.. We have burner issues.. There is a spider that loves to next in gas jets, clogging the jet and preventing ignition. I've cleaned quite a few spider nests out of assorted gas jets.. NOT, so for, on the RV, but on other stuff.

Next we have the ignition point (Assuming it is and ESI system) you should HEAR it sparking, and if you can observe the points you should SEE It sparking. I have seen points way, way, way out of adjustment (Reset them and years later that furnace was still functioning properly)

Next we have the thermocouple (Flame sensor) if it's bad it signals the control board "NO FLAME, Safety shut down"

Now we have the control board and last the gas solenoid

And that is just about the list for the symptom (no heat) you have

Most of 'em are easy to fix, and with the exception of the control board and solenoid, not too expensive