Greenhouse Heating

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Gaz

Greenhouse Heating

Post by Gaz »

We have decided to go for electricity this year after getting fed up of sooty damp parrafin. Should be cleaner and more efficient with a thermostat keeping the temps to about +5 or so. Two layers of bubblewrap should keep some of the heat in (i hope)

What does everyone else do for winter warmth?
mushtaq86

Re: Greenhouse Heating

Post by mushtaq86 »

Gaz i have put two layers of bubble wrap inside my greenhouse,dont know how much heat it will keep in.I am using elec fan heater,it was the best option for me,any other source of heating would have created to much work for me.
Andy Martin

Re: Greenhouse Heating

Post by Andy Martin »

Gaz... My greenhouse and plants got "sooted" last year. I was talking about it with Grub, who I went to visit today. The trouble is to get rid of the fume, one had to ventilate the greenhouse. To ventilate the greenhouse you let all the heat out icon_scratch . My thanks to Grub for his hospitality and generosity( I got a Musa Basjoo and a Colocasia F.O.C). Top Man icon_thumleft icon_salut
Guy

Re: Greenhouse Heating

Post by Guy »

Fan heater with a separate plug electronic thermostat. I find the thermostat in the heaters to be pretty useless and to either keep too warm and waste electric, or worse too cold and deaths ensue. Also have a large soil cable propagator made from double wall polycarbonate on top, which is cheap to keep at higher temps for smaller plants.
petr

Re: Greenhouse Heating

Post by petr »

These gas heaters from Bio Green look quite interesting
http://www.greenhousewarehouse.com/Gas- ... 21CT7.aspx

Especially the "Bio Green Propane Gas Greenhouse Heater 1.9kW"

Image

£100 is not cheap, but it has a thermostat, cheaper to run than electricity and I certainly won't be able to run armoured cable underground from the house for less than £100
Don

Re: Greenhouse Heating

Post by Don »

I think a lots depends on what temperature and the type of plants you wish to grow/overwinter. The disadvantages of the Biogreen system is that it produces a lot of wet air and higher ventilation is required just at the time of year when you want drier air and less heat loss. If I could afford to heat to 25C during winter then I would welcome all that hot moist air it would work wonders for Musa.
Petefree

Re: Greenhouse Heating

Post by Petefree »

I had one of those bottled gas heaters - it was quite good the first winter, apart from the need to keep the louvre vent open due to fumes and it did keep humidity higher than I would have liked. Unfortunately, when it came to the second winter (I had kept the heater in the greenhouse through the summer as they recommend bolting them down (which I did) I found the heater unusable as the heating bit of it, with the tiny holes for the gas, had rusted up very badly. I suspect I may have avoided this if I'd removed the heater in the spring, but don't think the instructions suggested that, and I'm a big fan of 'damping down' in the summer which I'm sure led to the corrosion.
I now use electric fan heating in the greenhouse.
I don't necessarily want to put you off the gas heaters - it was fairly cheap to run and quite effective and the heat level easy to control - but thought it worth pointing out my pitfall.
Pete
Steph
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Re: Greenhouse Heating

Post by Steph »

Gaz wrote: What does everyone else do for winter warmth?
Give up any hope of using the conservatory, turn the radiators OFF and squeeze in as many plants as possible, under the table, on the table, on the floor & in the roof....

Does amuse the neighbours.
Petefree

Re: Greenhouse Heating

Post by Petefree »

Steph wrote:
Gaz wrote: What does everyone else do for winter warmth?
Give up any hope of using the conservatory, turn the radiators OFF and squeeze in as many plants as possible, under the table, on the table, on the floor & in the roof....

Does amuse the neighbours.
:lol: :lol: :lol:
It sounds fantastic, Steph
Please post us a pic of it when it's full!
Pete
paul h

Re: Greenhouse Heating

Post by paul h »

Given that I mainly grow succulents I use electric :) all heaters are on rod thermostats as the heater one's do not seem acurate :( I also use mainly tube heaters as they are cheaper to run 2foot about 120 watts with a number of fans on time switches to get good air movment
I found Fan heaters expensive and no air movment if it was not cold :evil: also I do run an air cycling system 12 volt similar to the hole in the ground with gravel these seem to give me a couple of degrese extra with, and with a soil warming cable in them wired to the main stat an inexpensive boost :D
Ali K

Re: Greenhouse Heating

Post by Ali K »

I've always used an electric fan heater and adjusted the thermostat until I got it about right which usually means being in the greenhouse on the first frosty night fiddling with the knob for a while :lol: :lol: :oops:

Sounds a bit haphazard but it's always worked for me.
Guy

Re: Greenhouse Heating

Post by Guy »

Ali, it works but not well. If you buy a five quid digital max/min thermometer you may be interested in the results. Using the in fan thermostat the temperature will vary hugely. So to keep it above say 4c, it will be going up to at least 10c. Using a seperate thermostat will keep it within a couple of degrees. ie 4-6degrees. The saving on electricity will quickly pay for the thermostat. Certainly that's what I've found but i'd be intrested to see if others disagree.
Ali K

Re: Greenhouse Heating

Post by Ali K »

Maybe I've just been lucky then Guy, whenever we've had a frost the greenhouse max min thermometer has gone down to 4-6ºC and I've re-set it several times just to check. Perhaps I should try a separate thermostat though just to be safe.
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Dave Brown
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Re: Greenhouse Heating

Post by Dave Brown »

I have used bottled gas, but electricity is far more manageable. :wink:

Gas was the only option in my polytunnel at my mum's back in the 70s, but caused massive condensation and things rotted. The final straw was when the thermostat stuck off in a very cold spell in 1978 and my whole non hardy collection was gone, including my first ever banana. The heater was scrapped and a lean to conservatory built. which was heated by fan heater. The polytunnel was just a cold greenhouse from then. I have not used gas since.

My current set up here is 18 x 10 conservatory primarily heated by dehumidifier and solar energy. The 220w dehumidifier keeps condensation away which allows in the sun. There is a backup fan heater for colder nights. The humidty remains around 50% which stops too much from rotting. it also gives air movement.

Next to the consevatory on the opposite side to the bungalow is the garage on one East part, and the covered area on the other, so no external walls/glass. Any heat loss from the conservatory heats the garage and covered bit. To the North is Aido's room, any heat loss from there heats the conservatory and to the west the bungalow, so any heat loss also heats the conservatory. The only external parts with heat loss are the south facing double glazed end and and the triple glazed policarbonate roof. All in all does not take a lot to heat and benefits from the property heat loss, although we have tried to minimise that. icon_salut I had this built in my green days trying to reduce my footprint..... now it is just plain economic sense. icon_thumright

For anyone planning a green house the siting will determine what you can grow, and how much it costs to heat.... go for the sunniest winter spot you can find. Another thing.... throwing an old duvet cover over the roof on long cold winter nights can save you a fortune, whatever form of heating :wink:
Best regards
Dave
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Roll on summer.....
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MarkD

Re: Greenhouse Heating

Post by MarkD »

The paraffin heater we used last winter gave me a fright once :twisted:

One winter morning I was at the patio near the house when I sniffed something burning on the air and I thought someone was having a bonfire somewhere. Then when I went down the garden I saw our greenhouse full of white smoke and all the smoke are gushing out on every available crevice it can get out off. I thought the greenhouse was on fire!!! :ahhh!:

I didn't know whether to ring the fire brigade or inspect it first but I chose the latter as I can't see any flames nor the area felt hot, and as soon as I've opened the door out came all the smoke and to realise it was puffing out loads of smoke due to the flame being yellow :evil:

Thankfully nothing was damaged, only the plants all got sooty and the greenhouse stank of paraffin for weeks. But the really annoying thing was....despite all of that it only went 1C higher than the outside overnight temperature :evil: :evil:

So electric it will be from this winter onwards!! :lol:
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