Ask Experts Questions for FREE Help !
Ask
    Garzato's Avatar
    Garzato Posts: 2, Reputation: 1
    New Member
    		  
    #1

    Nov 4, 2006, 07:40 AM
    Both fans continuously running, but neither heat or ac kicks on
    This is a '93 Goodman gas model furnace. From what I have read, I believe it may have a bad limit switch. Where would this be located and how can it be tested? There is a small Black component (roughly 3x2")with a Blue on/off switch located on the furnace where gas passes. I believe this may be the limit switch. ANy ideas, if this is it or if any other component can cause the above symptoms?:confused:
    NorthernHeat's Avatar
    NorthernHeat Posts: 1,455, Reputation: 132
    Ultra Member
    		  
    #2

    Nov 4, 2006, 08:31 AM
    Both fans? Indoor blower and draft inducer blower? Main limits don't typically cause both those fans to fun. It is brobably a roll-out limit. See PC board for a diagnostic light blinking. Roll-outs have a small botton on the top of them, if you gently push it it will click if they tripped. Labman has made several posts this month describing what these look like.
    Garzato's Avatar
    Garzato Posts: 2, Reputation: 1
    New Member
    		  
    #3

    Nov 4, 2006, 09:55 AM
    Yes both fans were running. I could unplug start cap on small fan, turn switch in unit closet , and small fan wouldn't come on, but could hear other internal fan still come on. I removed and reseated hose from one sensor, removed to check clean other components. (Thermoswtiched, flame detect). After this I turned switch back on in closet, and fans still came back on. I went to thermostat to select heat while fan was running, raised setting to above current temperature, waited, ignitor never came on or burners. Then, I only switched thermostat fan from auto to on, and the furnace ignited. After igniting I switched thermostat from 'on' position back to auto. When the temparture matched the setting, burner did shut off, and fans turned off slightly afterwards like normal. Seems to be working, now, but may have an intemittant problem and something is going out. I suspected/suspect a Limit switch. I will try to find labmans descrp.
    NorthernHeat's Avatar
    NorthernHeat Posts: 1,455, Reputation: 132
    Ultra Member
    		  
    #4

    Nov 4, 2006, 01:30 PM
    Quote Originally Posted by Garzato
    Yes both fans were running. I could unplug start cap on small fan, turn switch in unit closet , and small fan wouldnt come on, but could hear other internal fan still come on. I removed and reseated hose from one sensor, removed to check clean other components. (Thermoswtiched, flame detect). after this I turned switch back on in closet, and fans still came back on. I went to thermostat to select heat while fan was running, raised setting to above current temperature, waited, ignitor never came on or burners. Then, I only switched thermostat fan from auto to on, and the furnace ignited. After igniting I switched thermostat from 'on' position back to auto. When the temparture matched the setting, burner did shut off, and fans turned off slightly afterwards like normal. Seems to be working, now, but may have an intemittant problem and something is going out. I suspected/suspect a Limit switch. I will try to find labmans descrp.
    Did you look for tripped roll-out or spill switch limits?
Not your question? Ask your question View similar questions
 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Heat pump AHU fan runs continuously [ 2 Answers ]

I have a 12 year old Trane Xe1000 heat pump. Recently I noticed that the fan keeps running continuously even when the outside unit turns off. It's as if the tstat fan switch is set to On (it's not) instead of Auto. I tried a few things: 1) In the tstat (weathertron) I disconnected the fan...

Blower kicks on and the pilot goes out [ 3 Answers ]

Hello all! I have a Trane XE 60 Gas Furnace. I have replaced the Thermocouple and have gotten the pilot lit. The gas will come on and the flame will warm the heater unit?? When the blower motor comes on, it blows out the pilot light and it won't re-light. Any Help!! Please!! Thank you

Heat comes on and kicks off hot tub [ 1 Answers ]

I bought a hot tub and it worked fine for three months. The problem I am having is heat comes on and kicks off hot tub. I replaced the gfci on the electrical side and nothing. I put a fan on the controls and it seem to work (heated up all day then kicked out again) any help would help. Thanks again

Heat won't stop running [ 3 Answers ]

I just moved into a new house, well new to me. It has a heat pump system. I'm not familiar with them at all and need some help. I took out my old mechanical thermostat and replaced it with a programmable digital thermostat. Now my problem is that the heat won't quit running. I don't know if I have...

Running furnace fan without heat [ 5 Answers ]

I read some of the other similar posts. I am encouraged that there is a way to do without a spot for the green wire. Labman, could you give me directions on how you to accomplish this. Thanks so much! Nate

View more questions Search