||09-02-2014 08:25 AM
Ok kids, listen up. Heil, heat exchangers. the law says 100 ppm CO out the exhaust for your furnace. Have this checked. Look for water under your blower you can't explain too. Black exhaust inside your vent pipe can be an indicator. This is serious. I have actually saw furnaces putting out 1900 ppm out the exhaust. You say ok but it's going outside so no problem, WRONG... If this breaches to the inside of the house due to a crack, death occors at 1200 ppm in 1 to 3 minutes. This is no scam and no joke. Get it checked. If that heil is 6 to 10 years old, get it checked.
The problem is the secondary heat exchanger. Another thing to look for in the Heil is rings falling off the primary heat exchanger, you may see a ring laying in the bottom of your furnace. That's it. Most of these fall off above where you can't see it. Flame rollouts are a good indication something is very wrong with your furnace. Pressure when it's hot may get inside the heat exchanger and cause a mild blowback. Heat shuts off the flame rollout. Heil and Carrier both have issues with this but no recall as of yet. As far as not lighting, it can be the flame rod. If no pilot flame it can be a clogged orifice. If flame sensor cleaning doesn't do it, replace the flame rod assy. bout 100 to 120 bucks. If that doesn't fix it the gas valve might need replaced.
If your furnace heats up and goes out and the fan comes on, you have a board problem..... What's happening is probably the furnace gets too hot and the limit shuts off the furnace putting it in lockout mode and lockout is turning the fan on. Furnace cools off and then it retries ignition. If you have a heil or carrier furnace I would strongly suggest to get CO detectors for your bedrooms and where you sit most often.