Are natural vent gas stoves green, or even safe in a tight home?
user-901114
| Posted in General Questions on
There are three types of Vermont Casting gas stoves: Unvented, direct vent and natural vent. Natural vent relies on a 12ft straight pipe for draft. I have been gifted one and I’m wondering if there’s anything I can do with it. I’ve got tight a home, a loose home and uninsulated camps and barns as options for its future.. Would like to use it in my zone 5 loose home that has natural gas supply but currently uses an oil furnace.
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Replies
Stephen,
You've got the good kind -- the one with a chimney. The one you want to avoid is the unvented kind.
Thanks Martin, Do you know if the chimney can take bends? And if not, what type I should get? Can't find any literature on it...
Or better yet, have you ever seen one run up an existing chimney flu? It'll fit in my fireplace with 4in legs..
A chimney designed for an open fire is usually not suitable for a gas stove conection. There is a risk of condensation.
Contact a professional who will decide at the site what can be done.
With the proper dilution hood adaptors low-efficiency gas appliances can be vented into masonry & tile lined chimneys, can use lower-cost "B-vent" rather than stainless. The chimney height & diameter still need to be in the correct range for both the min & max heat output of the appliance though.
But a dilution hood without a flue damper can mean a huge passive heat leak & infiltration driver when the burner isn't running.
In Vermont Castings parlance "Natural Vent" only means that it takes it's combustion air from the room rather than being piped in directly. In a very tight house ANY combustion appliance that takes it's combustion air from the conditioned space needs to be tested for back-drafting while burning when all exhaust fans/clothes dryers/forced-draft burners (anything that actively de-pressurizes the house) are all running.
Unvented heaters are expressly dis-allowed in many areas, and are a bad idea even where they meet code.
With any heater, sizing it correctly for the heating load of the space in is critical for comfortable safe & efficient operation.