I want to add a propane heater to my 12x14 ft. standalone greenhouse. I know I need 24k BTUs of heat.

My question is: Do I have to install a vented heater, or can I get away with a regular unvented heater.
I will be growing tree seeds only, no flowers of any kind.

I live in Pennsylvania, Zone 6.

 

Hi,
I really don't know the answer as I use a kerosene torpedo type heater of 55,000 BTU's in my greenhouse that is 14'x32', and I have a couple of places where there a some gaps along the bottom edge that I have just left alone and fill them with foam insulation pipe for 1/2" copper pipe, when it gets to cold. I haven't had any trouble with air quality. I personally would talk with your local fire department and building codes department about the type of heater you are thinking about or have, and what venting might be required. Some of the heaters today use pvc pipe to supply the fresh air and run the same kind of pipe for the exaust gases. It's better to be safe than sorry.
good luck,
Trent

 

Hello Grower. You Must Use A Vented Heater!! I,ve seen what a faulty heat exchanger ( wich is the same as a non vented heater) in a gas fired unit heater does to plants in a greenhouse, it kills them! and it can do the same to you! Plants (and people) can not tolarate the high concentration of carbon monoxide. Use a vented unit, the kind that draws outside air for combustion is best. Your btu sounds low, have you checked charts for your zone and glazing meterial ? I need 250k for my 15'x20' glass house in zone 5. Good Luck. Sam

 

Hi,
I am using a Sears 55.000 Btu kerosene forced air heater
that is approveed for indoor use. I service it every season and use fresh K1 only. I have been using this for years now with no problems. As I said I do have a couple of places where air does get in. I use a thermostat set at 72-75 degrees and it has no problem keeping it warm. I live near the Greater Cincinnati International Airport in Northern Ky. zone 6 I have 6mil uv poly film for the cover which has now been on for 6 years.
I have been using another heater of the same in my wood shop which is 24 x 50 with no problems also. Any heater that is not serviced or looked at can be dangerous. Look at the people overcome by fumes from their home furnace.
good luck,
Trent

 

I have been considering heating my greenhouse (450 Julian- 8 X 7). A local business man services chainsaws, mowers, and kerosene heaters. I asked him about using a kerosene heater in my greenhouse or in my home with my 15 month old daughter. He said " the typical kerosene heater that has had the chimney cleaned (or new heater) and been rewicked will leaave the air 98% fume free and clean. The second year the air quality drops to only 75%. The third year he said wasn't even worth mensioning." As long as you have your kerosene heater maintenanced every year and use a good grade of kerosene- your plants should be fine, too. He said that he serviced kerosene heaters starting around $40 to $50 here in WV. Good luck, too....wvspidermonkey