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Gas line for ventless heater

2374 Views 14 Replies 7 Participants Last post by  roughneck
I want to install a 30k BTU LP vent free heater in my shop, which is about 80' total from a location in my house where the gas line for my appliances, HVAC, water heater, etc has a spare outlet capped off for future use. Its a 3/4" LP line, the black coated flexible metal type), after my outside regulator, but my individual appliances that use it have their own regulators as well.



What would be the best material to use to run from the tap under the house (I have a male 3/4" NPT thread to connect to. Ive been looking at the yellow plastic type coiled pipe since it will be run underground between the house and shop, and transitioning back to black iron pipe for the end of the run connection. Is 3/4" large enough to provide an adequate supply, and is the yellow plastic IPS pipe even a good choice? Thanks!!
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Ventless will add a lot of moisture to the space.
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3/4" is more than adequate for a 30k unit.
In fact you could get away with 1/2"
But as Nealtw said...ventless heaters will add a LOT of moisture.
Is a vented heater out of the question for you?
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Un-vented heaters aren't magic, they still produce CO, they just dump it directly into the heated space along with all that moisture. You have to use it with lots of ventilation or your eyes will be burning and your head pounding. Brother in law heated his shop with an LB white, couldn't be in there an hour before it was making me sick. Do yourself a favor and install a vented unit so you can close the doors and be warm.
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Thanks for all the tips about the heater, is the IPS plastic piping good to use though or should I go with something else?
I had a small ventless heater installed about 8 years ago along with a standby generator for the many power failures we have had here.
They use the yellow jacket line for all of the underground piping.
No issues of any kind.
Vent free isn’t meant to be a primary heating source. In a shop the burner could be exposed to many various sources of dirt and cause poor combustion.
There’s a reason these things have been outlawed in many areas.
If you insist on using a vent free device make sure to open a door or window and get a low level non-UL listed CO alarm.
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Un-vented heaters aren't magic, they still produce CO, they just dump it directly into the heated space along with all that moisture.
I think you meant to say CO2 (carbon dioxide) not CO (carbon monoxide). Carbon monoxide is lethal and ventless heaters have several safety mechanisms built in to prevent CO production. Carbon dioxide is, indeed, produced by ventless heaters (along with water vapor). This can give you headaches if the concentration rises above about 4%.

Ventless heaters aren't intended to be a primary (or continuous) heat source but they have their uses when installed and used as intended.
Back to the OP.
About your shop.
Is this a home owner / hobbyists shop or an area where you work 8 hours a day?
By now you have read all of the cautions and advice.
If you can crack a window open when using the ventless or you have enough air infiltration it will be fine. But regardless of your situation there will be moisture.
As you use the heater it will produce gasses. It also burns the air in your rooms which magnifies the problem. It is actually taking air away from your living space, shop space in your situation. High efficiency furnaces have a system that is a flue pipe and a fresh air pipe. That supplies air for the burner.

Have you mentioned how big your shop is? Insulated? Any other issues?
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I think you meant to say CO2 (carbon dioxide) not CO (carbon monoxide). Carbon monoxide is lethal and ventless heaters have several safety mechanisms built in to prevent CO production. Carbon dioxide is, indeed, produced by ventless heaters (along with water vapor). This can give you headaches if the concentration rises above about 4%.

Ventless heaters aren't intended to be a primary (or continuous) heat source but they have their uses when installed and used as intended.
Most gas burners even when properly tuned make a little bit of co. It may not take much to cause health problems when the exposure is long enough.
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I think you meant to say CO2 (carbon dioxide) not CO (carbon monoxide). Carbon monoxide is lethal and ventless heaters have several safety mechanisms built in to prevent CO production. Carbon dioxide is, indeed, produced by ventless heaters (along with water vapor). This can give you headaches if the concentration rises above about 4%.

Ventless heaters aren't intended to be a primary (or continuous) heat source but they have their uses when installed and used as intended.
Maybe in a perfect world. And if you install a nice shiny new unit that has all those safety measures in place. There's millions of old units floating around that don't have any of that. Unfortunately most of them get installed and forgotten about anyway. Few will ever even get cleaned let alone properly serviced or tuned, especially in a garage setting.

Their "supplemental heat" status alone should make them useless as a main source of heat for any space, but people buy them believing they're a good solution. Cut in a vent and install a real heating system or just use electric. Unvented is too wet and too dangerous for me.
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Back to the OP.
About your shop.
Is this a home owner / hobbyists shop or an area where you work 8 hours a day?
By now you have read all of the cautions and advice.
If you can crack a window open when using the ventless or you have enough air infiltration it will be fine. But regardless of your situation there will be moisture.
As you use the heater it will produce gasses. It also burns the air in your rooms which magnifies the problem. It is actually taking air away from your living space, shop space in your situation. High efficiency furnaces have a system that is a flue pipe and a fresh air pipe. That supplies air for the burner.

Have you mentioned how big your shop is? Insulated? Any other issues?

its 25x30 two story (1 1/2 actually, barn, its insulated, the thing is I have only one large window in the front and its on the upper level.. im not sure how that would work out for the airflow and it would probably pull condensation out of the floor (concrete slab)
It will be fine for airflow. All of the heat will be going up anyway.
The heater won't need to pull any condensation from the slab....it will make enough on it's own. Sounds like your needs would be better served with a vented unit with a circulator fan.
Even a hanging type furnace would be a better choice.
just say no to ventless.
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Ventless appliances have been outlawed for a reason in many areas.
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