Vented and Non Vented Heat

[bucs012]

Ok. You guys have helped me a lot along the way of having my 50x30 stick garage built.

Question- I have read a lot about vented and non vented heaters. Electric/gas.

How does a VENTED gas heater differ from an Electric heater running in a garage that has a window cracked to vent air?

My garage is very well insulated and has soffits/vents up at the rafters that allow fresh air up there tpo. Does that count at ventilation?

Help me understand this whole concept. Bottom line is I don't want to come in someday and have everything ALL wet............My garage will be heated to 40-45 degrees when I am not in there and maybe 60-65 when I am on weekends.

 

[Gary S]

Electric heat doesn't consume any oxygen because it has no combustion. Therefore, with electric heat, you don't need ventilation.
Non-vented fuel heaters do consume oxygen so they need an outside source of oxygen or they will deplete the supply. Vented fuel heaters if designed right already have an outside oxygen source so they don't deplete the oxygen you need in the garage to live.

 

[tcianci]

I think you may be talking about non vented with respect to the heater exhaust. Water vapor is a combustion by-product and if you run a non vented gas appliance in your garage, you will be letting water vapor into the air which will condense on any surface that is cool enough. As stated, an electric heater does not pose an issue as there is no combustion present. Your best bet for a gas-fired heater is to choose one with a "sealed" combustion system. This means the combustion air is drown from outdoors and the heater exhaust is vented to the outdoors. There is no open flame in this type of heater which may be a plus for a garage. No combustion exhaust moisture is released into the buildiing, there is no danger of carbon monoxide build up from the exhaust and since the combustion air is drawn in from the outside, you are not exhausting air that you have already paid to heat.

The venting you mention about your building is for the purpose of "cold roof" construction. It allows for air to enter the building at the soffit and travel up behind the roof sheathing and exit at the ridge. This prolongs the life of the roofing (although some folks say it ain't so), lowers the attic temperatures in the summer and helps prevent water leaks from ice dams in the winter.

 

[bucs012]

Thanks for the info. That would make sense why my old Kerosene- bullet type heater made lots of condensation in my old garage......... It was one of those that fired up, loud, had a blower and flame out the front.