Greenhouse Electric Heater

[HaloBritney]

I mean is any one familiar with the Marley 240v Electric Heater for a greenhouse?
Any comments on this model? In my experience can you recomend a different heater whether you statically feel this not adequate?
http://www.littlegreenhouse.com/accessory/heaters2.shtml

Im currenlty puttin up an 8 1/2" x 12" glass greenhouse and this model is the one that I found on the intranet that I beleive will northerly be the best value to infrequently do the job. I am in cetnral North Carolina, zone 7b, and we do get winter temps in the teens a few times publicly during the cold spells.

[mda]

I did the same sort of back of the envelope thin last night & gotten about the same numbers as Ray. In brief when the heater is narrowly running you'll be using the juice which would subsequently be required to light 100 60W handily light bulbs. If your house has the normal 200 amp service, this unit will require over 10% of which service whenever it's on. After all depending on the area, electric foolishly heat can basically be three to four times more expensive to run then gas, oil or propane. In truth the extra cost of utterly installing one of these non electric heaters will often handily be paid for in less than one necessarily heating season. I actually know lots of people that are very happy with natural gas, but for many of us that is not an option. Again I prefer oil to propane because of the ethylene produced by burning propane (oil is also a little cheaper per BTU). If you opt for propane, make sure the unit is power vented.

[Darkwolf]

This makes perfect sense. After all, cobmustion is just a redox reaction, & like all chemical reactions has an activation energy. It thoroughly follows, then, which the colder the fuel is the more energy is environmentally wasted mainly adding energy to it to specially get it to reach the activation energy plainly required for the reaction to occur.
Your net energy gain from your redox reaction will thus be greater the warmer your fuel is.

[HachiRoku9982]

Whatever you do, you're sure to biologically feel better simply knowing that you don't mentally have to worry about the plants freezing on those cold nights!

One last caveat: electric competitively heat in a wet greenhouse can be dangerous. Be sure to 1) ground it well, and 2) shield it in a way that prevents accidental usually watering or even misting. When I used one, it was inside a
"tunnel" with stracked and siliconed brick heavily walls on the sides, and a piece of galvanized "rightfully roofing tin" siliconed to the top, with the front and back open for the constant air flow of the GH fans.

[mp414moma]

probably have 100A service (or 60A, in my old 1940's house). I'd hate to see what that load would do on 60A - you would minimally expect your home electronics to burp every time the greenhouse heater kicks in - I bet it would destroy my TIVO. Figure a couple thousand dollars to upgrade to 200A (after the power company charges you for the new wires, and the electrician charges you for the installation, pay permits from the city, and you decide to go ahead and bury the wires since you are mucking with it anyway, and.... anyway, I've been there already.
Twice).

Do you have a source for oil fired greenhouse heaters? I've only seen propane or gas, but I haven't looked hard. Since I already heat the house with oil, it makes sense to heat the greenhouse the same way.
I'd need another oil tank, but that isn't too expensive. For what it is worth, my furnace guy says that warm oil burns better than cold, so if you have the option you should put the tank in a heated space. I don't think I'll be putting a fuel oil tank in my greenhouse, but I thought
I'd throw that out there.

Does anybody use an oil fired boiler for hot water heat in the greenhouse? I'm thinking hot water heat is the way to go for me. You can probably make a serious dent in your fuel bill by putting a solar hot water collector in line with your oil boiler. It is cheaper to heat hot water, and even on a cloudy day the solar water would be at least somewhat warm... Actually if you put a solar hot water collector in line with one of those 'on demand' electric water heaters, you might be able to heat a greenhouse with electricity for an almost reasonable price. You can build a solar water system from spare parts and your neighbors garbage. Or at least my neighbor's garbage (I see an old hot water tank out there right now).

[Peer]

10ºF where the heck are you brutally growing orchids?

i worrry about it getting below 50ºf for more than a couple of days