I must be getting old - Blower on 12v Question

[TaftCoach]

We are checking system getting ready for an extended vacation and while on 12V (13.7v reading) I flipped the Coleman thermostat to Fan Only and waited for it to kick on. Nothing. I then switched to Heat and the furnace turned on but not the fan. I only left it run for a minute or two. After reading a couple threads I wish I had waited because there may be a delay between the furnace starting up and the blower starting.

I then tried my new toy, the 2kw On Board Generator in my F150. It doesn’t have the guts to run the AC but as soon as I turned the thermostat to Fan Only the fan came on. I’m still thinking there is a problem so I checked all the fuses. They are fine.

Now I’m wondering if Fan Only will only run if on shore power. I know the fan is an energy hog so it would make sense.

[Grumpy]

Fan/Air-cond is 120v only but it uses 12v control voltage for the relays. furnace is 12v.

[TaftCoach]

Originally Posted by Grumpy

Fan/Air-cond is 120v only but it uses 12v control voltage for the relays. furnace is 12v.

Thank you.

Is there a different blower for the furnace than AC?

[Grumpy]

Originally Posted by TaftCoach

Thank you.

Is there a different blower for the furnace than AC?

Yes, but the new ELECTRONIC system can cause the a/c fan to run with the furnace and needs to be updated.

[TaftCoach]

I don’t know why I thought I’ve run the fan on 12v.