How can I connect or wire my new thermostat for fan on to my 1984 coleman heat only mobile home furnace? It is currently not wired to do so , and I don't think the wiring is in place to do so.

Thank you for any help
Bob

You may not be able to do so without replacing the entire control package.

Is there a switch in the furnace to manually kick the blower on? If so, I believe Grady is correct. The older units were not set up to have a fan on option through the thermostat. But if you have the switch in the furnace, you can always just use that.

If I remember Coleman properly, I don't think they use a Honeywell fan/limit and if memory serves me right, depending upon the control box, they might have a rocker switch which when turned to the "fan on" or "fan" positiion, kills power to the burner. Pictures would be a huge help.

Thank you for responding to my question, there is only a control box cut out switch, can I install a blower switch on the leads powering the blower motor?

They already go through a switch of some sort (most likely temperature operated). I'd have to see a wiring diagram or at least pictures of the wiring to be able to tell you where you could put the switch.