Suburban Furnace works good.....Sometimes

[Fearless1]

Suburban Electronic fired furnace_Sometimes unit will not flame-on, but fan runs. Sometimes flame will go out before reaching desired temp, but fan keeps running (well over a couple of minutes). Sometimes cutting thermostat off and back on will make it work. Replaced thermostat and misfires are down but still there, as is flame out before temp setting. Also used steel wool to clean firing mechanism and flame sensor â€" same results.  i??

[Rickf1985]

Sounds like you need a new propane regulator.

[Fearless1]

Regulator is only 3 years old. Have it hooked up to 2-100 lb external tanks. Any way to check the regulator?

[Rickf1985]

You would need a manometer and check the pressure on the heater gas line. Another way to do it would be to have the heater on and then turn on a burner on the stove. If the burner comes on good and strong and the heater dies off but burner stays strong then gas pressure is probably fine. Not very scientific but effective. Gas pressure is gas pressure and iot works all of the appliances. Just because it is only 3 years old means nothing in today's times. Chinese garbage can die in a week.


If you can light all of the burners on the stove at full force and they stay that way then the regulator is probably good. That is a pretty substantial flow.

[Fearless1]

Lit 4 burners on stove to max. Then turned on furnace, worked perfect this time all thru cycle, all burners still max.  i??

[Rickf1985]

Could be oily residue in the propane lines if it sat for a long time. I found that in mine. I replaced the lines and had no issues after that but I also replaced my regulator at te same time so I don't know which was the worse problem.

[Fearless1]

Thinking about your replacing of the gas line, I took a look underneath at mine with the thought of maybe replacing it. Upon inspection it looked like such a chore that just the thought of it tired me out and I had to take a nap. I might look again tomorrow.

[CapnDirk]

As Rick pointed out it could be a puddle of liquid (old) propane in a low spot.  Everything on my coach worked except the hot water heater.  After I took the regulator off the propane tank and let it dangle, oil cam out.  I replace the regulator and everything worked but the W.H.  Took the line off the W.H. and off the regulator at the tank then blew compressed air through it and got half a cup of oil shot across the driveway.  Worked fine after that.


Aside from that it could be the time delay relay or the control board.  How long in seconds from turning the thermostat on till the fan spins up?  I had to replace my time relay.

[TerryH]

Having had a similar problem last winter - of course - I replaced my regulator. As far as I knew it was over 20 years old and due for replacement.
To ensure I bought the correct one I took the old with me to a company that sold, serviced and installed various propane systems. Emphasis on 'service'.
I told the counter person why I was replacing it.
He called in a service tech from the shop area.
The tech started taking the regulator apart, and sure enough, a thick oily residue inside the regulator. Not a lot, but he said it was more than enough to affect it.
He recommended, besides the replacement, to clean out the primary line from the tank to the manifold. Instructions were to disconnect the line at the manifold (already was at the tank, of course), fill the line at the tank with methyl hydrate. let it sit for 10 minutes. Then blow it out with compressed air.
Do the same from the manifold side.
Leave the line disconnected at both ends for an hour or so, then blow out from either end again.
He said the residue accumulation begins at the propane source to regulator, but seldom travels beyond a point in the primary line very far from the regulator.
Line replacement sure doesn't hurt, but not necessarily required. Depends on the condition of the line. Your decision.
To date has worked fine for me.

[Fearless1]

CapnDirk, it takes 10-12 seconds for fan to come on.

[Rickf1985]

That is about the same as mine.

[CapnDirk]

CapnDirk, it takes 10-12 seconds for fan to come on.

That would indicate that the delay is working correctly.  About 10 seconds of fan coming on (no flame to purge the heater box) , and 1 minute going off to cool everything (flame is off during that time to of course).


So, clogged line, regulator, control board.  In that order, the cheapest to the most expensive to replace.

[Fearless1]

Anyway to check the control board? I've got a hammer and a hacksaw.

[Rickf1985]

I have found that my 44 mag works great, If I stand in just the right spot I can fix the heater and water heater at the same time.

[Fearless1]

Correct me if I'm wrong, but I believe that is referred to as "Perfect Alignment."  :)rotflmao

[Rickf1985]

 

[RANGERRICK]

Don't forget the igniter.

[CapnDirk]

Correct me if I'm wrong, but I believe that is referred to as "Perfect Alignment."  :)rotflmao

Friend of a friend was out hunting with the wife when they see a doe on the next hill over (few hundred feet).  He says this ones yours honey and they get out the drivers side slowly and kept low.  She looks across the hood, sights in, and pulls the trigger not realizing that the muzzle is a few inches lower than the scope.  Put a round through the hood and top of the radiator.


True story!   :)rotflmao   

[Fearless1]

I'm going to go out on a limb here and say the wife may have been a blonde.....at the roots anyway.