Heil Furnace Problems - HVAC - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 10-20-2011, 09:33 PM   #1
Newbie
 
Join Date: Oct 2011
Posts: 3
Rewards Points: 10
Default

Heil furnace problems


I have high efficiancy Heil furnace. It ignites and runs fine but shuts itself off after a few minutes and flashes the 6-2 code which is soft lockout, flame sense lost during run, pressure switch off, or blocked condensate. It will reset itself after apx 10 minutes or if I cycle the thermostat to heat off and then back on. I have had a furnace repair company out twice and after a couple high bills I still have a furnace that wont run continually. Its fine for normal operation, it can usually maintain temp, but I have a programmable thermostat so in the morning when the furnace has to raise the temp of the house 10 degrees it cant do it. So far I have tried multiple flame sensors, a gas valve, pressure switch, checked the little hose that goes to the pressure switch, checked to make sure the condensation is draining and getting pumped away. If anyone has any advice it would be greatly appreciated.

Advertisement

nj1984 is offline   Reply With Quote
Old 10-20-2011, 11:10 PM   #2
Member
 
Join Date: Oct 2011
Location: pa
Posts: 4,615
Rewards Points: 2,544
Default

Heil furnace problems


what you are explaining sounds like limit switch problem....you could jump it out and try it????although does not match fault code.....still worth a try

Advertisement

ben's plumbing is offline   Reply With Quote
Old 10-21-2011, 12:17 AM   #3
Newbie
 
Join Date: Sep 2011
Posts: 29
Rewards Points: 25
Default

Heil furnace problems


Where in your house is he unit located? How cold has it been? When does it seem to fail? Overnight or randomly throughout the day?
thestig3 is offline   Reply With Quote
Old 10-21-2011, 08:03 PM   #4
Newbie
 
Join Date: Oct 2011
Posts: 3
Rewards Points: 10
Default

Heil furnace problems


Thanks for the tip but I forgot to mention I had already replaced the limit switch as well. I tried jumping it anyway and it didn't make any difference. The furnace is located in the center of the basement. At night it has been getting down to the 30s. It fails every time it needs to run longer than a few minutes. If the temp in the house is 60 it will maintain that temp because it only has to run for a few minutes to maintain that temp. But if I tried bringing the temp in the house up to 70 it will run for a few minutes then shut itself off for 10 minutes and keep doing that. In the middle of winter it cant raise the temp because it will drop a degree or two while the furnace is rebooting itself so it can never get ahead.
nj1984 is offline   Reply With Quote
Old 10-21-2011, 10:30 PM   #5
Newbie
 
Join Date: Sep 2011
Posts: 29
Rewards Points: 25
Default

Heil furnace problems


My guess would to be to check for obstructions in the combustion air system. PVC for combustion/flue correct? If so, I've found a yellow jackets nest in combustion line starving system of air. Or condensate droplets forming into ice at the pressure switch orifice due to near freezing combustion air temps.
thestig3 is offline   Reply With Quote
Old 10-22-2011, 12:06 AM   #6
how
Member
 
Join Date: Feb 2011
Location: Vancouver BC
Posts: 1,546
Rewards Points: 608
Default

Heil furnace problems


A crack in the exchanger may open up after the furnace heats up to effect your pressure enough to trip your pressure switch. See if you can see a difference in the main burner flames through the view port by watching the whole heating cycle up to the lock out.
The vent motor may start slowing down after it has heated up which affects your pressure switch. Listen to it's rpm for consistancy right up till the furnace locks out.
Check that all your grounds are tight to there contacts. I just came from a job that had a similar problem with a loose ground that was causing a lock out with false diagnostic indicaters. That loose ground was because an old lumex electrical line to the furnace was only loosely connected to the box holding a distant shut off switch off. The ground was actually the outside of the lumex jacketing that pulled away when the heating duct it was lying near heated up.
Tons of possibilities out there.
Good luck
how is online now   Reply With Quote
Old 10-22-2011, 01:08 PM   #7
Newbie
 
Join Date: Oct 2011
Posts: 3
Rewards Points: 10
Default

Heil furnace problems


I checked the air intake and did not see any obstructions. I started the furnace up and watched it while it ran. I did not notice any fluctuations in the flame or the vent motor. All 3 flames just abruptly shut off, it was very instantaneous, not like it was gradually losing gas or air. I shut off the power switch to the furnace and restarted it a few seconds later and it had trouble igniting, it tried multiple times. I could hear something clicking so took the cover off and and could hear and feel the gas valve clicking sporadically. When it clicked I noticed a slight variance in the pilot flame as it was attempting to ignite. I let the furnace sit for 10 minutes and then tried starting it again and it worked fine until it shut off again. Would I have to go in through the plenum to inspect the heat exchanger. Thanks everyone for the tips and advice.
nj1984 is offline   Reply With Quote
Old 10-22-2011, 02:52 PM   #8
how
Member
 
Join Date: Feb 2011
Location: Vancouver BC
Posts: 1,546
Rewards Points: 608
Default

Heil furnace problems


Until someone else comes along with a better idea for matching your symptoms against your checked and repaced parts...

You probably already know this but...
A long screwdriver pressed against the body of the gas valve with the handle pressed against your ear works well is an effective stethascope for identifying where a sound is coming from. Obviously don't hold the metal part of the screwdriver and keep it away from live wires.

Is the inlet for the air intake for the burners inside the furnace room"?
Is your gas coming directly from the meter or is it being reg,ed down with a 2lb regulater in the furnace room?

It sounds like your motherboard $$$ is probably the next item up for replacement but really go through all the green ground connections you can find first. Then check your ground connections through all the utility boxes(inside the furnace, the external shut off, and any add on splice boxes that might have been added to your supposedly designated circuit.)

The only good thing about your furnace finally not coming on at all is that it will make the diagnostics and repair of your unit by a proffessional much less of a hit or miss affair.

Advertisement

how is online now   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Water Inside/Around American Standard Furnace michrob HVAC 8 12-08-2011 04:51 PM
Heil Furnace Won't Turn On ada5011 HVAC 1 11-02-2010 08:29 PM
Heil Furnace Pilot Light Not Igniting shwank HVAC 13 10-07-2010 07:41 AM
Two Furnace Problems jaysinn HVAC 3 01-02-2009 01:20 PM
New Cased Coil - Install to Furnace - PICTURES!! hartkem HVAC 39 11-18-2008 02:45 AM




Top of Page | View New Posts