# Help With New Install



## velocitygraphix (Jul 14, 2018)

Hello everyone, I am building a house and getting ready to put the floors down but wanted to clean the ducts from dust/debris before I proceed. The air handler is installed with 240 power to it. However, the thermostats are currently not on the wall and just the wires coming out and I have tested the voltage. The red wire has 24volts on it. I wanted to run just the fan so it can blow through all the ductwork so it will alleviate the dust cleanout later. I connected the red and green wire together but the fan didn't run. I have checked the air handler and both disconnect breakers are turned on and the LED inside is on. Is there something that needs to be done to get the fan to just run? Does the thermostats need to be installed before i can run the fan? It seems like the handler is getting power to send to the thermostat since it has 24 volts but the fan is not turning on..Any help would be appreciated. Thanks!


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## faithheatingcooling (Aug 16, 2018)

sounds to me that there is a problem with the wiring at the air handler low voltage or G wasn't ever wired in. Try disconnecting the disconnect to the outside unit and connect the y and r at the tstat. that should run the fan only.


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## faithheatingcooling (Aug 16, 2018)

How did this work out for you? Curious


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## Steven123cool (Mar 2, 2021)

I agree that G was never hooked up or whatever fan speed G is (usually high) may be shot. Try a different speed. Thinking maybe you never worked on a furnace. Is there only one stat ? Zones. If you turn on your fan : 1 of 2 things will happen; 1 you will suck dust into your furnace or 2 you will blow dust through out the house. If its been off during construction; clean vents locally and you should be good. Do not turn on the fan or run it at all until new filter and entire place clean! Just a thought


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## Sm_raudales (Jan 18, 2021)

Important things to know about fan control.

You can run your system’s fan independently of heating or cooling. So your system doesn’t need to be actively heating or cooling to run the fan.
However, you can only run the fan when your thermostat is set to a temperature mode (like Cool mode, for example). 

You cannot run the fan if your thermostat is set to Off. 
You can set the fan to run a fixed schedule or manually set it to run. It can’t be set to automatically run or switch off when you leave or come home.
You’ll see a fan icon on the temperature screen when your fan is running because of your fan schedule, or if you’ve turned your fan on manually.


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## Steven123cool (Mar 2, 2021)

Bad fan relay on or off the board and yeah how many stats you got. Sounds like more than one so find and check zone board. Ohm the wires by disconnecting at both ends and wire nutting two colors together at one end and ohm them out at the other. Did you find where to land a stat at the unit? It’s the green connected. You are probobly fucking with radiant heat stat wire anyways. Just a thought; make sure it’s the wire again by homing it out. Never assume it’s right, most systems I work on are done wrong from the beginning and can head down hill fast. Ohm it out to see if it is indeed the right wire. No contractor?


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