Why is my furnace fan constantly running?
Why is my furnace fan constantly running?
When your thermostat is set to AUTO, your furnace fan should blow only when your furnace is in the middle of a heating cycle. But if your fan runs constantly, regardless of whether your furnace is heating, that’s not normal. There’s a shorted thermostat wire. There’s a shorted wire at the fan limit switch.
Why does my heater not work on high speed?
Heater blower motor will not work on high speed? I have replaced the black bosch relay behind the glovebox, the blower resistor and the blower motor and still cannot get the blower to work on high. I remember in older model years of gmc’s and chevys that their was a high speed blower relay that caused this issue.
How do you turn on a high speed heater fan?
Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high. The fan should be blowing on high, now wiggle the connector one more time the fan should stay on without interruption.
What to do if your heater fan does not work?
Now gently grab ahold of the red and black wire connector and wiggle it if your fan came on you have found the problem. Now if this worked for you remove the positive battery wire from the battery because the red wire at this connector remains hot.
Why does my GMC heater blower not work?
I have replaced the black bosch relay behind the glovebox, the blower resistor and the blower motor and still cannot get the blower to work on high. I remember in older model years of gmc’s and chevys that their was a high speed blower relay that caused this issue. If there is a high speed relay, I can’t find it. Any suggestions?
Why is my AC heater fan not working?
This sounds more like a problem with high speed fan relay. On the low speeds, the fan relay routes the voltage thru the resistor block. When you switch to high fan speed, the relay switches over to supply full voltage from the battery to the fan motor.
Why does my fan only run on the highest setting?
Most commonly the fan will only run on the highest setting. This is a well documented problem, and is caused by a failing blower motor resistor. Correcting the problem is straight forward, and requires replacement of the small resistor. The resistor is normally found behind the glove box, next to the blower motor.
What happens if you run your air conditioner fan too fast?
Watch out: running the blower speed too fast during air conditioning may result in inadequate dehumidification, while running the fan at too-slow a speed may result in ice blockage on the cooling coil. The blower fan motor in most air conditioners has three speed settings – low, medium and high.
When to use high or low fan speed?
There is no single “right” fan speed for all heating and cooling conditions and both high and low speed settings have uses and advantages. Higher air speeds are needed during the cooling season than during the heating season.