Greenhouse heat

[Yuba]

ello. I'm new to the forum. I search and read the forum all the time but my first time posting.
I'm looking for help with heating 2 greenhouses. One is 1200sq ft and the other is 432sqft. I live in northern California below the snow line. I am trying to keep to a budget so I am looking to put an indoor forced air furnace in the large one and some sort of wood stove in the small one or maybe a pellet stove. I know allot off people use outdoor wood boilers but they are a little expensive. I would like one one day. I am thinking about the Englander furnace or daka for the big one. These are around 1200$.
For the small one, I am not really sure. It's a small space and it is covered with double layer poly. I'm worried it will get to hot in there and then it will be freezing come morning.
Things to add: the small one I am going to re-cover with double layer poly and will be used only in the winter. The big one will be used march - November.

I wanted to know what you guys thought about the cheap wood furnaces and which ones have the biggest firebox for the money. Also some ideas for the small greenhouse. Something to mention is that live off grid. I have a decent solar system with backup generator but power is conserved whenever possible. I live on 20 acres of oak and madrone and wood here is easy to come by.

 

[maple1]

Being off grid, maybe a couple of wood stoves?

Englander NC30s? Think they're big, capable, efficient & reasonably priced.

(Whatever you burn it in, the wood needs to be dry. So next years wood should be cut stacked & drying now).

 

[Yuba]

Thank you for the reply!. I accidentally made 2 posts. Does anyone know how to delete one?
I'm thinking about the Englander 28-3500 or the daka 621 or whatever has the biggest Firebox size in that range. I am having trouble finding information about firebox size. I am trying not to wake up in the middle of the night if I can help it. I would like a furnace so I can run ducting down the greenhouse so it will heat evenly and circulate air.
I'm off grid but my solar system will have no problem with some furnace blowers.
I do know how to season wood. I heat my house with an older lopi. Hardwood like oak and madrone is really cheap to free here.

For the smaller greenhouse Its such a small area it will be hard not to overheat or be filling every couple hours. I have been thinking about getting a used non epa airtight stove (like a schrader) that I could really choke down. I know they aren't efficient. I know creosote would build up.
Maybe a cheap pellet stove.

I heat my house with wood. I have never had a wood furnace though. I have never heated a small space with wood. My only pellet stove experience was almost 20 years ago and that thing was problematic.
Maybe I do need to bite the bullet and get a wood boiler. But I don't know anything about them and it seems like it would be expensive after pex and heat exchangers but I don't really know how much they cost and there might be an affordable option.
Thanks

 

[Fred61]

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[Yuba]

Thanks for your reply fred. I have seen those. They are a cool concept.
This is the boiler room. Does anyone have any suggestions for furnaces. Biggest firebox for price. They are not sold in California so I can't just go to a store and compare. I'm going to have to choose a furnace and drive out of state to get it.
Please someone.

 

[sloeffle]

The Tundra / Heatmax is the best value IMHO for an EPA approved furnace. I would stay away from non-EPA approved appliances since you will burn more wood and make more creosote. Their is huge thread about the Tundra / Heatmax on this forum. Here is a good overview of that conversation.

 

[Yuba]

Thank you sloeffle. It does look like a nice furnace. Drolet claims that it uses 40-50% less wood then a standard wood furnace. I know the new epa stoves are more efficient but is it really that much? I don't have much experience with new stoves. I have an old lopi 380/440 heating my house. I'm pretty happy with it but I have never had a newer stove to compare it to.
I am not really worried about overall wood consumption but if it gets me significantly longer burn times, it may be worth it. If the Englander won't make it through the night but the drolet will, it might be what I have to do. I was hoping to get something less expensive until I had time and $ to upgrade to an OWB that could heat both greenhouses and possibly my house. Is 3000$ starting to approach on OWB pricing? Especially after you consider another 1500+ for the pellet stove to heat my other greenhouse.
I know the best greenhouse heat is root zone heating with pex.

 

[maple1]

An OWB install would involve underground piping at $10+ per foot....

 

[Yuba]

Well I just went to clean my 25+ year old lopi 380/440 (old endeavor) and the only air tube is broken in half. The blower also died when I went to go start it up this year. Considering it's age it might not be worth fixing. Replacing the house stove with a new 2000$+ endeavor, wood furnace and a pellet stove with auto ignition. It's getting me close to wood boiler pricing. I have existing ducting in my house for propane. Not to mention, I am only at that house maybe one day a week during the winter so it would be my grounds keeper loading up the stoves. It might be easier for him to keep an OWB fed then a pellet stove and a wood furnace. My neighbor at that house is a retired plumber and offered to help with install.

 

[maple1]

Have you fully priced out an OWB setup - the whole thing?

Using a good OWB, and proper underground piping?

 

[Dantheman300z]

Sounds like you should fix the Lopi put it in one of the greenhouses and buy your house a different stove.

 

[sloeffle]

Drolet claims that it uses 40-50% less wood then a standard wood furnace. I know the new epa stoves are more efficient but is it really that much? I don't have much experience with new stoves.

Yes, you will burn less wood in an EPA approved wood burning appliance. The environment will also appreciate you buying an EPA approved appliance too. As I get older, cutting wood is also becoming a lot less "glamourous". Can you even buy a non-EPA approved wood burning appliance in California ?

Is 3000$ starting to approach on OWB pricing? Especially after you consider another 1500+ for the pellet stove to heat my other greenhouse.

I don't think you can find a good ( Portage and Main, maybe CB ) OWB for under 7K. You are probably looking at an extra 2k - 3k in "goodies". Good underground piping is at least $10 a foot as @maple1 pointed out. I would expect to be 10K deep for an OWB install.

An OWB also seems overkill for your situation. If you were to find an non-EPA approved OWB for a good price then I hope you like cutting wood. I have a couple friends that have them and they burn between 7 - 10 cords a year. No thanks, I'll stick with the two cords a year that I burn in my EPA approved furnace.

 

[Yuba]

So I figured out the small greenhouse. Pellet stove on thermostat someone had recommended here. It's really working great. I think I decided on a yukon polar oil/wood for the big greenhouse. My house is off grid and I have a 500 gallon off road diesel tank that I could share with the furnace. This seems like the right move.
There is a used yukon polar for sale here for 2500. My question is, what should I be looking for when I go to look at the furnace? Any weak points? It is older, have the polars changed much over the years?
My other options would be a new polar, or a pellet furnace.
Thanks!

 

[byQ]

I may be in the same boat at some time - heating a greenhouse. I will just build an ugly masonry heater for less than a $1000 in materials. Costs kept down by using a clean-out door for main door and free stone or brick for the outside. With an eco firebox this is one of the cleanest burning ways to burn firewood.