advice / solution needed to heatup a greenhouse

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SilverNodashi

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I have a 5m x 5m x 2.5m greenhouse, with plastic sheeting (not glass) and I need to keep the ambient temperature to 10c or 15c during the night.
There's currently a 2000w fan heater in, which raised the temp by about 2c - 3c during the night, but it was still 4c this morning and some plants have some "frostbyte". So I need to go and buy at least two more, but 6kw for 10 - 12hours will cost a small fortune to run on Eskom. So I need something more cost effective.

I have considered putting in some black water pipes, full of water, but don't yet have a workable solution for a heat source, during the night. Will a solar collector and circulation pump, during the day, heatup the water in the pipes warm enough to sustain some heat during the nights?
I prefer not to burn any wood or gas inside.
 
Is frostbyte the only thing you are worrying about?What about those white covers for plants?
 
SoftDux-Rudi said:
I have a 5m x 5m x 2.5m greenhouse, with plastic sheeting (not glass) and I need to keep the ambient temperature to 10c or 15c during the night.
There's currently a 2000w fan heater in, which raised the temp by about 2c - 3c during the night, but it was still 4c this morning and some plants have some "frostbyte". So I need to go and buy at least two more, but 6kw for 10 - 12hours will cost a small fortune to run on Eskom. So I need something more cost effective.

I have considered putting in some black water pipes, full of water, but don't yet have a workable solution for a heat source, during the night. Will a solar collector and circulation pump, during the day, heatup the water in the pipes warm enough to sustain some heat during the nights?
I prefer not to burn any wood or gas inside.
Click to expand...



Can you post some photos ?

Sounds like fun ...
 
Game have a 4 bar heater for R799 that comes on a stand.
I would get one of those, make sure all the flaps and such are sealed nicely so that the hot air can not escape and then add a small oscillating desk fan to the mix to spread the heat out evenly.

http://viewer.zmags.com/publication/a1d4b76f#/a1d4b76f/1

Fan.png

The heater will produce C02

I would also go a bit more technical and add a thermostat to the heater, that way you can leave it on all the time. it will keep the greenhouse warm till the sun is warm enough then turn off and at night when it even starts to get cold it will kick in and start regulating the heat so that it does not have to fight to get a freezing room to warm up.

a 5-50'c thermostat at van biljoens is about R200 to R250 and will do the job nicely.
Keeping the temperature constant will increase the growth speed of your grass or "tomatoes" as you prefer to call them optimal and winter will assist with the night cycle slight cooling you want. :p :D
 
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AstroTurf said:
Game have a 4 bar heater for R799 that comes on a stand.
I would get one of those, make sure all the flaps and such are sealed nicely so that the hot air can not escape and then add a small oscillating desk fan to the mix to spread the heat out evenly.

http://viewer.zmags.com/publication/a1d4b76f#/a1d4b76f/1

View attachment 124653

The heater will produce C02

I would also go a bit more technical and add a thermostat to the heater, that way you can leave it on all the time. it will keep the greenhouse warm till the sun is warm enough then turn off and at night when it even starts to get cold it will kick in and start regulating the heat so that it does not have to fight to get a freezing room to warm up.

a 5-50'c thermostat at van biljoens is about R200 to R250 and will do the job nicely.
Keeping the temperature constant will increase the growth speed of your grass or "tomatoes" as you prefer to call them optimal and winter will assist with the night cycle slight cooling you want. :p :D
Click to expand...

That heater is 1600w. I already have a 2000w fan heater, which helps with circulation, but it's not quite enough. It's on a timer from 8pm till 8am (imagine my electricity bill...) and it's still not enough, but helps to keep the plants from freezing at least. This morning, at about 4am it dropped to 3c inside. Otherwise it's generally about 7c during the night, inside.

I put some 2 black dustbins inside with water, will see it it helps a bit tonight.
 
SoftDux-Rudi said:
That heater is 1600w. I already have a 2000w fan heater, which helps with circulation, but it's not quite enough. It's on a timer from 8pm till 8am (imagine my electricity bill...) and it's still not enough, but helps to keep the plants from freezing at least. This morning, at about 4am it dropped to 3c inside. Otherwise it's generally about 7c during the night, inside.

I put some 2 black dustbins inside with water, will see it it helps a bit tonight.
Click to expand...

Fan heaters are not nearly as hot as carbon fabric.
you will be able to save some cash if you use this as well.

The reason I say use a thermostat is because it will maintain the temperature in the room as opposed to trying to warm it up after it's already cooled down.

You may even be able to get away with just sticking a thermostat on your fan heater instead of a timer but I doubt it.

Easiest way to see is to try though.
I would buy a thermostat and an enclosure for it then wire that to the live of an extension cable (so the live feeds through the thermostat) and plug the fan into it to see.
If it does not hep you will need more heat.
 
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