WeatherMaker 8000, Blower remains on too long - http://www.hvacmechanic.com/ Forums


Original message

Jell-O

68.12.21.187

"WeatherMaker 8000, Blower remains on too long" , posted Mon 21 Jan 13:29user profileedit/delete messagepost reply

I live in a rental property and don't own the home's central heating unit, but I'm curious about this possible problem with a Carrier WM 8000.

I believe the system ignites properly - a process that takes about 80 seconds before the blower comes on. The blower and flame will remain on(on average)for about 1:15. Thereafter, the flame extinguishes, but the blower will remain on for an additional 1:30 to 2:15. This effectively cools the house back down, necessitating a rather quick restart of the entire cycle.

I know nothing about HVAC, but I assume this behavior is abnormal and increasing my heating costs. I also wonder if it is in anyway dangerous. No LED codes are flashing.

Any suggestions would be greatly appreciated. I'm praying for some low-cost options to present my landlord. Thank you in advance.

 


Replies:

yuri



207.161.171.185

"Re(1):WeatherMaker 8000, Blower remains on to" , posted Mon 21 Jan 20:15:user profileedit/delete messagepost reply

The burner should run for 5-10 minutes to warm up the house and be off 10 minutes and repeat the cycle (approximately). Sounds like your thermostat is short cycling. It may have a heat anticipator which is set too low. If it is an old mercury style CAREFULLY remove the front cover and look at the dial with a wire on it. Try slide the pointer CAREFULLY to where it says .6 or .8 for a longer cycle. If it is an electronic type then you may need a new one or check it's instruction manual to adjust the cph (cycles per hour). Make sure your air filter is clean and all your vents are open. May be cycling on the limit control.

Good Luck

Yuri

[this message was edited by yuri on Mon 21 Jan 20:18]

 

 

Jell-O

68.12.21.187

"Re(2):WeatherMaker 8000, Blower remains on to" , posted Thu 24 Jan 17:40user profileedit/delete messagepost reply

Hey Yuri,

Thank you very much for the tip. I am amazed at how well this has helped my situation. I believe I may still have an additional problem, but your suggestion now has the burner cycles running from 2.5 to 4.0 minutes - long enough to allow the house to become fairly comfortable (on this, the coldest day of the year here in Oklahoma).

The period between burns is much more lengthy than before, perhaps as much as 10 minutes - which really makes me feel better about my system, which used to cycle on about every two minutes.

I do have two additional questions for you, if it's not too much trouble.

1) Do you know if it is within the normal range of this unit for its blower to remain running for approx. 2 minutes BEYOND the burn stage, or does this represent an additional malfunction? I really believe that the home's comfort is negatively effected by this long "cool-down" period.

2) I may be using the wrong terminology but I'm curious, why would the thermostat have been set with it's heat anticipator at .3? Is there some disadvantage to opting for a .6 or .8 cycle?

Lastly, I can't tell you how pleased I am with the information you provided. Such a simple adjustment has made this house so much more livable, I can hardly believe it. Thank you for taking the time to help out a stranger. Regardless of whether the unit has an additional problem, this level of performance is quite acceptable. God bless ya!