Author Topic: new greenhouse planning  (Read 42697 times)

spaugh

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Re: new greenhouse planning
« Reply #175 on: April 14, 2018, 11:17:52 PM »
You can get a few solar panels and a charge controller and a deep cycle battery to run everything offgrid for pretty cheap.  The beauty of solar for a GH is it will only need to work when its hot and sunny.  Anyways its way cheaper than the 4K you mentioned.  A generator is good too but will need to be manually started and setup unless youa are dropping big bucks on an automatic backup system.

Power went out at my house today for a few hours.  Had to run the generator to keep my GH fans and mist runinning.  It was 85 and 7% humidity outside and GH was over 105.

I have 50% aluminet and its still cooking inside the greenhouse unless the fans and mist are running.
« Last Edit: April 14, 2018, 11:32:08 PM by spaugh »
Brad Spaugh

loneroc1

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Re: new greenhouse planning
« Reply #176 on: June 15, 2018, 09:51:21 PM »
Howdy all,

I've been watching Brian's project for a couple of years now. My 32 x 16 greenhouse with in-ground plantings is up and running, though I went for pressure treated and redwood construction, glazed with operable glass units for the walls and uv transmitting double walled acrylic for the roof.

I'm in zone 3/4 and when it's -20°F out two 30K btu heaters keep temps well above freezing. My goal is just to keep things just above freezing.  Here's my dilemma: I went with one Southern Burner ventless heater which needs no electricity to operate, not even a battery for the thermostat. (The other is a direct vent propane heater which requires an electric thermostat.)  When I bought the SB it was advertised as coming with a thermostat that would go down to 35F. Just above freezing so I was fine with that. I want the SB to be the primary heater. Well, when it arrived it came with a RoberstShaw millivolt thermostat that could only be set down to 39F.  When I called to inquire/complain I was told that RobertShaw thermostats now only go as low as 45F. and SB was aware of no other millivolt thermostat that had a lowered set temperature. I found another 39 F stat on ebay so I have a backup, sort of. I'd rather  not heat to 39, let alone 45. Is my SB furnace soon to be useless?  I like the reliability of needing no electricity.

The best suggestion SB could offer was to try to find an old millivolt thermostat wit a mercury switch and mount it on a slant.    My, what a helpful suggestion that was.  How can I operate the SB at near freezing temperatures? Or is my desire to heat without electrical back up doomed?

Any ideas? Thanks! Steve H SW WI USA USDA Zone 4.

Mark in Texas

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Re: new greenhouse planning
« Reply #177 on: June 17, 2018, 08:11:53 AM »
Howdy all,

I've been watching Brian's project for a couple of years now. My 32 x 16 greenhouse with in-ground plantings is up and running, though I went for pressure treated and redwood construction, glazed with operable glass units for the walls and uv transmitting double walled acrylic for the roof.

I'm in zone 3/4 and when it's -20°F out two 30K btu heaters keep temps well above freezing. My goal is just to keep things just above freezing.  Here's my dilemma: I went with one Southern Burner ventless heater which needs no electricity to operate, not even a battery for the thermostat. (The other is a direct vent propane heater which requires an electric thermostat.)  When I bought the SB it was advertised as coming with a thermostat that would go down to 35F. Just above freezing so I was fine with that. I want the SB to be the primary heater. Well, when it arrived it came with a RoberstShaw millivolt thermostat that could only be set down to 39F.  When I called to inquire/complain I was told that RobertShaw thermostats now only go as low as 45F. and SB was aware of no other millivolt thermostat that had a lowered set temperature. I found another 39 F stat on ebay so I have a backup, sort of. I'd rather  not heat to 39, let alone 45. Is my SB furnace soon to be useless?  I like the reliability of needing no electricity.

The best suggestion SB could offer was to try to find an old millivolt thermostat wit a mercury switch and mount it on a slant.    My, what a helpful suggestion that was.  How can I operate the SB at near freezing temperatures? Or is my desire to heat without electrical back up doomed?

Any ideas? Thanks! Steve H SW WI USA USDA Zone 4.

I heated a small greenhouse with a SB ventless too and yes the thermostat went down to around freezing.  That was around the 80's.  I'd consult an A/C Heating technician.  We have one here that's a wizard when it comes to such oddball units, work arounds.  I had a heater failure, temps dropped to 18F for a while, tech came out, knew the problem, did a work around in an hour.  Cheap $100 well spent.  Melnor propane unit.

SeaWalnut

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Re: new greenhouse planning
« Reply #178 on: May 25, 2019, 02:49:23 PM »
Verry nice and informative thread.Thx Millet and Mark for their shared experience.The foundation of the greenhouse its like a bunker  ;D.

tve

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Re: new greenhouse planning
« Reply #179 on: May 26, 2019, 01:31:17 AM »
Quote
The best suggestion SB could offer was to try to find an old millivolt thermostat wit a mercury switch and mount it on a slant.    My, what a helpful suggestion that was.  How can I operate the SB at near freezing temperatures? Or is my desire to heat without electrical back up doomed?
Mounting at a slant sounds like a good idea to me... Your last post is a year old, so may not be relevant anymore, but if you have a friend who is handy with electronics he/she may be able to build/adapt an electronic thermostat for you, it really just takes a couple of components. The trick is that the thermopile can generate plenty of power for the electronics, just needs an appropriate boost or buck converter.

brian

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Re: new greenhouse planning
« Reply #180 on: December 09, 2020, 10:48:47 PM »
Today I went out to pick grapefruits and oranges while it was snowing, and it reminded me of what an incredible success this greenhouse has been.  The huge amount of work has paid off, I think this has been the best project I have ever done.  I bet you could build a greenhouse even farther north and get good fruit.  I would love to see somebody even farther north give it a try.   I bet you could grow grapefruit in Canada with a heated greenhouse.
« Last Edit: December 09, 2020, 10:50:53 PM by brian »

Millet

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Re: new greenhouse planning
« Reply #181 on: December 10, 2020, 11:48:28 AM »
My 72-ft X 32-Ft double poly greenhouse in cold snowy Colorado is located a 5440 ft. elevation.  In ground large greenhouse trees:  Cara Cara, Saint Teresa lemon, Dekopon, Ponkan mandarin, Sour Orange, Marsh Grapefruit, Pomegranate, Page mandarin, and Valentine Pummelo, plus many 13 gallon container citrus trees.  On a 17 degree below zero day, during a cold winter day, it is great to go into a 80F warm greenhouse full of green vegetation.  Summer 12 months a year.
« Last Edit: December 10, 2020, 11:51:34 AM by Millet »