Hi,

I have an annoying furnace issue.

During our last couple of cold snaps, the bleeping thing quit in the middle of the night (2 times, a week or so apart). When I got up in the morning, I cycled power a few times and eventually it fired up.

The details:
1. It's a propane setup and the tank is at about 38% -- so the propane pressure is probably a little low
2. I can hear it try to start when it gets like this. It fires briefly and then a little later starts to get a good flame going, but it hits the time limit before it fires up.
3. I think that cycling power works because the igniters get a little hotter and also the propane starts to flow a little better

The furnace guy was out and looked things over ($$). He says that the timers are fixed and that basically there's nothing that can be done.

Not sure that he's right. It's happened before, but this is the first time it's happened twice in a relatively short period of time.

I do also burn wood and that keeps the furnace off a lot more -- don't know if that's contributing to the problem or not.

Appreciate any thoughts.

Thanks,

hj

 

1. Yes, the LP is a bit low...try not to let it get below 35. Colder areas make for lousy flow, especially if you're getting close to empty. No obstructions/kinks in the LP feed line? Filter is good? Blower/burner in good shape?

2. Is your exhaust clean all the way up, down & out---no obstructions/built up caked on dust or anything to stop the (horizontal) flapper from opening once she's fired?

3. The wood exhaust chimney is separate from the Lp exhaust, yes?

 

Extreme cold weather will reduce the rate at which liquid propane inside the tank vaporizes into gas. The problem gets worse as the liquid fuel level is drawn down. Easiest fix might be to have the tank filled. And make sure your tank is not covered in frost, buried in snow or shielded from the sun.

Smaller tanks can be especially problematic in colder climates because there's not enough surface area to maintain the required heat transfer to vaporize the fuel. And again low liquid fuel level makes this problem worse.


Is the furnace room getting any heat when you burn wood? Part of your problem might be the furnace is getting too cold to function properly.

Next time the furnace shuts off try warming up the furnace room with a space heater and see if that helps it start any easier.

It might be a combination of your tank not delivering enough gas pressure on cold days and the furnace not running well when the basement gets too cold.

 

This is a touchy subject for me...

When I was a kid maybe 14ish, my parents hired a company to change our oil system to gas... Company came out at 7am and left by 6pm, I recall it was a big crew and a big company up in Connecticut.

That night we went to bed and at 3am BOOM, our house was totally up in flames after a huge explosion. I still remember this terrible time in my parents life. At the end we were all able to evacuate without getting hurt, but to this day it's something I could never forget. I always remember myself and my parents sitting in an indoor porch from our across the street neighbors house watching our house burn for hours and eventually to the ground.

My point is please have that system checked out!

 

Thanks for the concerns guys

Yes, furnace and woodstove have separate chimneys
Yes, furnace has been checked ( afgain today) -- it's only 8 years old

Checked furnace room temp and it stays between 45 and 55 -- probably actually a little warmer when the wood stove is burning.

Have a good woodstove setup and I've been burning wood for nearly 40 years.

I do think it might be a low propane flow problem -- although it's 1000 gallon tank . Could be that these igniter type furnaces are more sensitive.

I will be calling my propane folks. I'm on keepfill, but they should be out pretty soon. Just checked the level and it's on 40. I'll ask if they can check the pressure.

hj

hj

 

Is it a hi-efficiency furnace (PVC air intake and exhaust)? If it is the Circuit board will have LED lights that will blink status codes, resetting the power will delete the code and restart the system from scratch.
Had the same thing happened recently on my furnace and after resetting the power several times it would work for weeks flawlessly then always at 2-4AM no heat and had a code for flame failed to ignite and was diagnosed and fixed for a randomly miss functioning igniter. Without the code it would've been a shot in the dark at parts or a new furnace.

Edit, a 1000 gallon tank will easily supply enough propane for a house furnace even if it's down to 10% at 0°, I have been there and couldn't afford to fill it that week, The thermostat was set pretty low during that time... Slightly nerve-racking.

 

Another common issue is the flame sensor, quick easy fix is to remove the sensor and clean it with some sand cloth. Re-install and go. When my furnace did this the igniter would light the flame but the furnace itself would not kick on. Kept cutting out and re-trying.

 

It's just a bit maddedning.

Never had this kind of issues when I had a pilot light

Furnace guy checked everything out -- says it's good. He's not the best troubleshooter that I've ever seen, but he's pretty competent and his workmanship is very good.

No helpful lights or codes on this one -- still have a chimney.

Propane folks are going to check the pressure to make sure there aren't any regulator issues. I agree that the tank should be good. I've gone through -30 or so witho no problems.

hj