furnace run time

[bluestreak]

Hello. Since having a new control board installed in my 25 year old carrier furnace,I notice after the burner kicks off,the motor only runs for about a minute and a half,then stops. There is still hot air coming out of the registers.It seems to me it should run a little longer. Is this adjustable? Thanks so much for any info. GREAT SITE !!

[mayguy]

25 years old?? I am not aware of any furnace that old having a board controling the fan off time.

most boards has a setting for fan off delay, sounds like yours need to changed. If the board has nothing, and like most older furnace, there is a fan limit-control.

[bluestreak]

Thanks for the reply,mayguy. I guess I ment the circuit board,not the control board.Is the fan delay part of this NEW board the tech installed ? I paid $400.00 for it,and I hope it is adjustable!! The fan stops running with the register temp of 106 degrees.seems like a waste of hot air left in the registers .thanks again.

[Gunnery Sergeant Hartman]

You should've put that $$$ into a new furnace...

[BaldLoonie]

Probably the HH84AA020 board and it should have some adjustment to it though probably not over 2 minutes.

[bluestreak]

Your right,baldloonie. The hh84020 board was replacd,and then my problem started. I just couldn`t see throwing out my furnace because of a sticking heater fan relay,bschvac,but I would of never guessed it would be so expensive. So you say this is adjustable ?? Thanks for the reply !!

[Chill]

Why don't you call the tech who installed it and ask him? He will probably come back and adjust it for you.

[bluestreak]

Well,thanks for the replys. At least I know there is an adjustment on it.

[Furnace_dude]

Originally posted by bluestreak
Well,thanks for the replys. At least I know there is an adjustment on it.

if its not working right [which it isnt] the technician should come back out and fix it for free. just call the company and tell them that you had just had the board installed and you dont think its working right.

[docholiday]

I would certainly want to know the actual temperature rise while it's running. I suspect it is high if you still have a 30+ rise a minute and a half after the burner shuts down. You may have an airflow issue all or the fan speed may not be set correctly.

[bluestreak]

Thanks for the replys,furnace-dude and docholiday.I would call the tech back out, but the board was replaced 1 year ago.Seems a little late. Should have called sooner. Air flow problem,doc ?? I did shut off the registers to 2 room since my kids moved out. Maybe I will open them back up and see what happens.I have a pretty good digital cooking thermometer Can it be used to check the temp. rise ?? thanks again. You guys ROCK !!

[mayguy]

Yeah, take a temp reading and see what it's at just above the A/C coil, and return before the filter.

[Furnace_dude]

you should still have a year warranty from the instslling company. why not call and ask if it is still covered. the worst case, they would say you have to pay for them to come out.

[bluestreak]

well,I called the company back,and they are charging me for the service call. Only the board is covered IF it proves to be defective. I took a temp reading in the upper part of the plenum,it started at 73,topped out at 145,burner shut down,it ran for 1 min,45 secs, fan shut down,with a plenum temp of 107. then the temp climbed back up to 125. What a wast of hot air !!! I did this test 3 times during the day, with the same results. thanks guys. he comes out on the 9th,and I will let you know the outcome.

[bluestreak]

Well,I guess my troubles are over, the tech came out,charged me, and told me my heat exchanger has a small crack in it. I am now the owner of a Trane xl-80. Hope I get some good years out of it !! Happy Thanksgiving all !!

[mayguy]

Thanks for keeping us updated.

Like the quietness of the two stage, and comfort?

Hope you got a new two stage t-stat on it?