Overhead cab is cooler...

It seems the WC 840 cab access area is somewhat closed off because the bathroom is against the cabover area preventing the warm air from getting to the cabover. The problem is the furnace and the thermostat are very close together, so your thermostat will reach the desired temp when the cabover is receiving very little of the warm air.

You can't go wrong with a catalytic heater. I installed a Wave 3 Cat Heater with quick connect valve and extended hose we can move around the camper. I found the wave 3 does not cut it, but would work great if it was installed in the cabover area. My mod list includes a Wave 6 heater to put near the door, and using the wave 3 for the cabover area. I plan on using the propane line to the fridge, running it through the cabover ward, and mounting somewhere on the passenger side ward/window in the cabover. We will only need this when winter camping, so it is nice to be able to do the mod without a permanent install.

toedtoes wrote:
Could placing a 12v fan next to a duct and pointing it towards the cabover be enough to bring up some heat?

x2 simple is good. It should help.

I got two words for you: More blankets.

If I had to listen to the furnace cycle on and off all night long I would probably set fire to the camper after the second night.

I bought (2) fatigue mat sets from Harbor Frieght, it is a 3/4" dense foam and interlocking. On sale now for $9.99 four 24" square pieces.

http://www.harborfreight.com/anti-fatigue-foam-mat-set-4-pc-61607.html

They add insulation and some cushion.

We too like the cooler cab for sleeping

One thing that we did that may help you is buy the interlocking foam pads sold by numerous stores and place them under the mattress. We did it for the cushioning but it it also adds to the insulation value. You just trim them to fit.

Example:

Interlocking foam pads at Amazon

Deb and Ed M wrote:
I trimmed Reflectix insulation (like bubble wrap with heavy foil on both sides) to fit in the windows of our larger RVs; plus added vent "insulation pillows". Just using those, we were able to keep our 32' 5th wheel warm enough just with a small electric heater in outside temps in the 20's

Do you get that at a Home Depot? Never heard of it! Thanks!

Johnny G1 wrote:
The stock furnace in our 8.2' Big Foot will more than keep the camper warm in cold temps, set the thermostat @68-70 and you will cook in the overhead but set it there to keep the pooch and the cat warm in the floor of the camper if they decide to sleep there. Have used it many cold weather fishing trips, so what's the problem?????

Oh its not a matter of the furnace keeping things warm.
I generally like to keep it at 65 degrees and it does a fine job keeping the camper warm. Just the growing pains of a new camper and making sure our equipment is up to the task and if I can improve efficiency since I don't want to kill my batteries running the heater to keep the cabover to my liking. I don't think anything is "wrong" with the camper. In fact, I have had zero issues with the camper so far and I'm a picky person....who at one time used to build rv's for Coachmen.

bb_94401 wrote:
The fantastic fan dome is available as a double pane, really helps at minimizing condensation, which drips on you. During winter camping, filling in the vent opening and cab over windows with a closed cell foam or reflectix and sealing it at night makes it much warmer.

I'll check into that, maybe I can just buy a new dome.

I trimmed Reflectix insulation (like bubble wrap with heavy foil on both sides) to fit in the windows of our larger RVs; plus added vent "insulation pillows". Just using those, we were able to keep our 32' 5th wheel warm enough just with a small electric heater in outside temps in the 20's