Honeywell Thermostat replacement help needed

Well, I just went through this myself, same honeywell thermostat, but different old analog one. I had two multi cables going to the thermostat, one from the roof A/C unit and one from the furnace. The hardest part of mine was figuring out which wire did what because the wire colors didn't match with the conventions.

My switch was set to gas.

Below, the first color is the wire and the second is the thermostat connection.
Red to Red - this is 12V +
Blue from AC AND Blue from Furnace to Blue - this is 12V -, if I only connected one of the blues, the other unit wouldn't work.
Yellow to Yellow - compressor
White to White - furnace
Green AND Grey to Green - This will make the fan run on HIGH when it is called for. The honeywell doesn't have a high/low speed fan function.

After I got it sorted out, it works great.

Good luck.

I have fan set to "auto" and like you state, if fan is on "on" it just runs continuously.

To get it working the way it is right now, I had to set the HG/HE switch to "HE". When set on "HG" (as it should be), the A/C fan only runs when fan mode is selected to "on". The a/c fan then also runs when the heat come on. NO fan period when set to auto. but the a/c compressor does run, just no fan in auto mode.

A side note: This is the 2nd Honeywell stat I tried. The first was a little more expensive but I had the same problem with it, so I took it back. I got this one, at Lowes, as it was the exact model used by another camper in one of his mods, back several years ago. Same model but obviously not the same circuitry.

I wanted to move back to a Hunter as the one I finally got working in our old TT was working just fine BUT Home Depot, Lowes, Ace Hardware nor Wallmart carry the Hunters any more.

Also, the whole system still works as designed when I reinstall the analog stat.

I have tried several of the many wiring set ups offered by others, even one that blew the heater 15 amp dc fuse.

I would sure like to get this working and post on several forums a 2014 answer to the Honeywell thermostats, so others have an easier time making the upgrade.

Your help is appreciated!!

Wiring looks correct
RED (12v DC +) to R/RH
BLUE (12v DC -).......NOT USED
WHITE (12v DC +) to furnace
YELLOW (12v DC +) to A/C Compressor control
GREEN (12v DC +) to A/C Fan control (HIGH)
GREY (12vDC +) to A/C Fan control (LOW)

HG/HE switch should be on HG (gas)

Do you have FAN set to 'auto'?
If fan is set to ON it WILL turn on when furnace comes on.