If thermostat is set to 70-90 degrees the furnace burner and blower will run constantly and the temp never gets above 68 degrees in the house. I have a Lux programmable thermostat and was thinking of replacing it with a Honeywell. I have a new filter. Any ideas?

The weather has been in the teens, but this has not been an issue during previous winters.

Thanks

It could be that you have a problem with the duct work, possibly a joint came loose and you are losing most of your heat into an area that does not need it. Use a thermometer at the opening of one of your grills and check the temperature. If you find that the burner is going out or something let us know and we will try to help you.
First thing to always check is the filter. And dirty filter can cause all kinds of problems.

There is a new filter. I have just went over the duct work and evrything looks fine. Every time I check the burner as well as the blower they are going. It seems that they would run 24/7 unless I drop the temp below the air temp. I have another thermometer and have verified the air temp on the thermostat. By touch, the air from the grill seems warm, but not hot.

I imagine this is a huge waste of energy and money, but can it be dangerous as well.

Am I wrong in thinking that if I set the thermostat to 80 degrees that it should get to that temp in a reasonable time (30-60 mins). Of course I would not want to leave it set like that, just for troubleshooting.

Something is wrong with the furnace, I can't guess what based on the information provided. If you can post the furnace BTU, efficiency, and size of home maybe we can help. Watch the burners for about 10 minutes, do they cycle off and on?

If the furnace comes on, chances are the thermostat is working. Get back to Northern Heat with the requested info. You need to find and fix the problem with the furnace.

Input 73,000 BTU, Output 68,000 BTU, 80% eff, 24,000 sf home
Burner stays on and does not cycle
Today my house is 62 degrees and it is about 10 degrees warmer outside.

I think you made a mistake in the square footage of your house. I think you mean 2400 square foot, 68,000 BTU is a little small for that size house, assuming that you have the normal glass area of most houses that size, especially if the outside temperature is very low. How is the insulation in your house, if the insulation in the attic has settled or packed down from people crawling around up there that could be another reason for the lose of heat.
You say that today that your house is 62 degrees and the outside temp is 72 degrees. In that case your furnace should be able to catch up very easily. Is there any chance that you AC is running the same time that your furnace is. Just grasping at straws.

Okay, I called and had a professional look at the furnace. It was the LP input pressure that was too low causing the system to not achieve it's proper BTU output. I guess this was not set properly during installation. I am not sure why I did not experience these issues before. Anyway... thanks for the help and hopefully this info. May help the next person.

Okay, I called and had a professional look at the furnace. It was the LP input pressure that was too low causing the system to not achieve it's proper btu output. I guess this was not set properly during installation. I am not sure why I did not experience these issues before. Anyway... thanks for the help and hopefully this info. may help the next person.


If in the future, if you do have more questions it would help if you included more information if it is pertinent such as like in the above post you said it was a problem with the LP pressure, you never mentioned anywhere that it was an LP furnace which might have given someone an idea of what the problem might have been.

As from above...
3 yr old Goodman Gas Forced Air Furnace problems.

If it was unclear, basic troubleshooting skills may have inclined one to ask.

As from above...
3 yr old Goodman Gas Forced Air Furnace problems.

If it was unclear, basic troubleshooting skills may have inclined one to ask.

Yes you are right, I should have had the skills to ask if you were using LP gas, along with many other questions that I didn't ask but would have been obvious had I been there to see your equipment. But when you answer questions for people on ASHD you expect that the people posing questions on AMHD to include all that's pertinent to their problem. I will try to be more efficient next time.