How to balance ventilation and furnace heat

[lamimartin]

Hi, thanks to fall weather, I'm now experimenting how to use the Duotherm furnace I reinstalled two weeks ago in my Trillium 4500. I see that even at full power, the effect is not all that great if the dome vent is left opened. I think it is essential to leave a window opened, even if I know this furnace is sucking air from outdoor and returning it outdoor trough the exhaust.

Questions:

1. How should I set windows and dome vent to produce maximal furnace efficiency in cold weather ? (with safe and minimal ventilation maintained)
2. Is it realistic to expect reasonnable comfort over 15C or 60F even close to freezing point outdoor without condensation inside the RV ? I used to do that with a large tent trailer and a 6000 BTU catalytic furnace. I figure it should be possible with a smaller RV like a Trillium

[Kevin K]

When I run my furnace I do not open the top vent, I just crack open the small window over my stove.

[Darwin Maring]

What I would do is to purchase and install a Carbon Monoxide detector, install it and close the window and adjust the thermostat accordingly.

[Darwin Maring]

Catalytic will increase condensation and your Duotherm furnace should not. What condensation you will have should be from your breathing.

[Rick G]

Originally Posted by lamimartin

Hi, thanks to fall weather, I'm now experimenting how to use the Duotherm furnace I reinstalled two weeks ago in my Trillium 4500. I see that even at full power, the effect is not all that great if the dome vent is left opened. I think it is essential to leave a window opened, even if I know this furnace is sucking air from outdoor and returning it outdoor trough the exhaust.



Questions:

1. How should I set windows and dome vent to produce maximal furnace efficiency in cold weather ? (with safe and minimal ventilation maintained)
2. Is it realistic to expect reasonnable comfort over 15C or 60F even close to freezing point outdoor without condensation inside the RV ? I used to do that with a large tent trailer and a 6000 BTU catalytic furnace. I figure it should be possible with a smaller RV like a Trillium

1. I also use only the small window over the stove for a vent, cracked open only an inch at most. I have camped this way in my Trillium 4500 many nights and never experienced a problem. I have detectors. I agree that opening the roof vent lets all the warm air out. I am not concerned about the furnace using the trailer air (it is vented to the outside and sealed away from the inside air), but rather the occupants using up all the oxygen if the trailer is too well sealed. Another window or a leak in the door seal would work as well.

2. We have our thermostat set for 70 degrees F and get it all the time, even when the outside temperature is below freezing. Usually we have to turn the furnace down. We have never had a condensation issue except for once inside the rear bed storage compartment on the same side that holds the furnace. In the original trailer construction the storage compartment on that side was open to where the furnace was installed under the closet, making the storage compartment very warm and allowing condensation when it was in contact with the cold air outside the storage compartment. I installed a compartment wall similar to the one which was factory installed in the kitchen-side rear storage compartment, and since then we have not had any condensation.

Rick G

[lamimartin]

Thanks to you all !
Bottom line, a bit of window ventilation, but the dome shut (what I have not tried) should keep the place warm, dry and safe. We NEVER shut our window completely into our bedroom and the RV is no exception. Since the furnace has a combined exterior air intake and exhaust, I'm not concerned about the furnace, but our own biological oxygen supply. Without the furnace, the dome provides lots of ventilation. With the furnace, it sucks the heat right out !