Coleman EB12...how to run blower only

[Barb P]

Hi Robert.....
On thermostat, settings are *heat.....off.......cool*
Blower settings are.......*auto.....on*

I tried *cool*.......and *on*.................no blower.
I tried heat *off*.....and blower *on*.......no blower.


I would like to use it to distribute cool AC air, from window units throughout home.
Is this possible?

Thank you in advance, for response.

[Robert]

Hi Barb,

Set t-stat to OFF and Fan ON .


IF the blower does not come on and also does not come on in the COOL and ON settings, probably a bad fan relay or loose wire.


Thanks,
Robert

[Barb P]

Robert, the blower works with heat. Been using it until just recently.

I did use the settings you suggested.

Should I assume it doesn't work without heat?


Thank you.

[Robert]

Hi Barb,


In Cool-Auto, Cool-On, Heat-On and Off mode-On, the blower will run in high speed.


To get it to just circulate the air, set it for Off mode - Fan On .


You stated you have done this and it doesn't work.


That would indicate a bad fan relay, bad thermostat or loose/broken wire somewhere.


Does it work in Cool - Auto ?



Thanks,
Robert

[Barb P]

Robert, the fan doesn't work in any combination, that doesn't require heat.

Just to make sure, I turned on the heat, and the blower does work with heat.

This furnace doesn't have AC...I just want to circulate air.

Thank you.

[Robert]

Hi Barb,

Does your furnace or blower housing have a rectangular metal control box with switches on front for heat/off/cool and fan/on/auto ?


You will have to know if your blower has a high speed and if it does, is it wired up.

Also, does it have a blower relay installed.


Without a/c, it may or may not.



I will look at my books in a few and see what it says about your furnace in case you don't know the answers to those.


Thanks,
Robert

[Robert]

Hi Barb,


It does have a a/c compatible blower motor with high speed and it does have a fan relay.


So would need to test for voltage with a multi-meter to see if the fan relay was working.


Either it is not working or there is a loose or broken wire somewhere.


Your furnace should not have the control box with the two switches either, so disregard that.


Thanks,
Robert

[Barb P]

Robert,couldn't get a clearer pic. Switch box has 2 switches.

Top one controls blower.

Bottom must be for heat?

I had to turn the furnace on to test it.

Are you saying the blower can work with heat, but still may not work with blower alone?

Or are you saying it should, but there is something wrong?

Also I've searched both the User's manual, and the Installation Manual, and see no mention of running just the blower.
It's equipped for add-on AC.


Thank you for all your time spent:)

[Robert]

Hi Barb,


Those aren't switches, that's the furnace breakers.


Your furnace has the needed blower motor and fan relay, BUT the blower wiring from thermostat may not be wired through the relay for operating blower by itself.


This can be easily resolved by having an hvac tech wire the blower wire to the fan relay and then to the motor.


IF it is already wired in, then the relay is bad or a wire has come loose or broken.


Thanks,
Robert

[Barb P]

Time to call my favorite repairman......aside from you, of course.
Thank you Robert.

[Robert]

Hi Barb,


You're very welcome, happy to help.




Take care and best wishes,
Robert