We have a small cabin that has two rather old wall heaters. The first (and last) time we used them the odor was substantial and condensation really bad. Moisture on the walls.

But, lots of people heat with propane. Are there efficient wall heaters that do not require a vent to the outside? That do not create condensation in the room?

I would think all propane heaters require a vent to outside due to CO.

quote:

Originally posted by Gustofer:
I would think all propane heaters require a vent to outside due to CO.

They have some indoor units that are advertised as "ventless."

https://www.amazon.com/Mr-Heat...8f-cd087fee0848&th=1

Are you in an area where you have winter high humidity?
I have a Rinnai heater. It vents to the outside. A great heater. I do not understand how venting outside would affect humidity inside?
And yes CO is deadly so understand how things work.

The ventless heaters produce water as a byproduct of combustion and return it to the room with CO2.

This is instead of CO that is of course deadly.

The are supposed to shut off if the CO2 content vs the Oxygen gets too high.

I would put in a vent and just get a regular heater.

I have had one running on propane installed in a greenhouse for a little more than a year now. Vent free, no issues so far.

I have a small workshop in my pole barn that is heated by a small vent less propane heater. I have 2 different co2 detectors in the area and have never had either of them give off any warning. I have never noticed a problem of high humidity.
I originally put in a vented wall furnace but it only something like 75% efficient where as the heater is much higher.
My wife has asthma and can not tolerate being in the area when the vent less heater is used.
I would never use a vent less in an area where people are sleeping. (other then my occasional cat naps).

Having had a close call in an enclosed space, definitely put all the monitors necessary.

Low O2 makes people dumb.

I’ve almost died lots of different ways, but that was one of the dumber ones.

The monitor needs to go off at a very early stage, so your brain is still functional enough to realize what’s going on.

(We didn’t realize what was going on until we each realized the other couldn’t stop yawning. Neither of us noticed that we were constantly yawning ourselves).

Wall mounted vent less propane heaters are illegal here. I have a wall mounted vented Empire propane heater in my 8X16 ice fishing house. Gives me peace of mind knowing it's vented to the outside in such a small space. Every year there is at least one incident of one or more people punching their ticket due to succumbing to CO build up in a fish house. Most guys fall asleep intoxicated and don't wake up. Not a bad way to go but not in your 20's or 30's.

I have two ventless propane wall heaters by Empire Comfort Systems. One in a sunroom off the dining area and one in the lower level walkout. No problems with either but they were expensive.

Not wall mounted but I've run a ventless LP fireplace in the basement (finished) for 20 years. No CO alarms ever. I do run a dehumidifier as it does dump some moisture back in the space.

Two sets of gas log propane heaters by Heat n Glo. I will not run the ventless system (living room fireplace) for any reason. Too risky. The den system (fully enclosed and vented) does keep that space warm. I have 3 CO monitors, 1 hard wired, since we do heat our house with propane.
I am a maintenance nut on those 2 systems; original installers service them in my presence.
Blackhorse4

I have this unit. The orange flame ones are supposed to release less moisture. It's been a backup heater when power goes out or when it gets cold enough the mini split can't keep up.

https://www.amazon.com/dp/B07T..._b_fed_asin_title_26

Purchase carbon monoxide detector for both living room and bedroom if you're installing a vented propane heater, vented natural gas heater, natural gas fireplace, propane fireplace, and any other combustion heating where carbon monoxide is a by-product.

I have a personal experience with the vent freezing shut on a vented natural gas fireplace. When I lived in Alaska, I flipped on the gas fireplace and walked out of the room. A few minutes later, I came back and the cats were wobbling and I couldn't catch my breath. I flipped on the 1/2 baths exhaust (entry to half bath was from the room with fireplace), threw open the sliding glass door, and shutoff the gas fireplace. It was about -15F outside and the exhaust vent had frozen shut on the fireplace.

Our ventless fireplace is burning right now in the living room while we watch tv. No odor but condensation from combustion is unavoidable.

We've been using a ventless wall heater as our primary heat source for more than 10 years now. I can keep the house easily at 68 degrees with it until the outside temp drops to single digits. At that point our furnace will kick on and cycle.

I just checked, current indoor humidity is 39%. To that, we have not had to run a humidifier in years due to the condensation it produces.

It has an oxygen depletion sensor and I have a CO detector mounted about 12" off the floor.

As all the heat stays inside, it is very efficient. An added plus is that the furnace blower takes a fair amount of energy to run, our electric bills are usually at their lower point during the winter months.

If I was using one in a small space like a cabin (our house is about 840 sq ft), Id consider some make up air and double down on CO detectors.

quote:

Originally posted by tatortodd:
Purchase carbon monoxide detector for both living room and bedroom if you're installing a vented propane heater, vented natural gas heater, natural gas fireplace, propane fireplace, and any other combustion heating where carbon monoxide is a by-product.

I have a personal experience with the vent freezing shut on a vented natural gas fireplace. When I lived in Alaska, I flipped on the gas fireplace and walked out of the room. A few minutes later, I came back and the cats were wobbling and I couldn't catch my breath. I flipped on the 1/2 baths exhaust (entry to half bath was from the room with fireplace), threw open the sliding glass door, and shutoff the gas fireplace. It was about -15F outside and the exhaust vent had frozen shut on the fireplace.

Holy shiet !!!

Glad you're still here.... good lord.

quote:

I have a CO detector mounted about 12" off the floor.

What is the reason for this location ? I thought the sensors should be near the ceilings !

They can be at any height. CO is close to the same weight as air and mixes readily.

quote:

Originally posted by Gustofer:
They can be at any height. CO is close to the same weight as air and mixes readily.

Thanks Gustofer....now I know !