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Greenhouse Heaters

I currently have an 8x6 Greenhouse which is un - heated, last winter as you know was raher mild so although I didn't lose too many plants, I did lose a couple. However knowing my luck this Winter will be colder and just incase I would like to invest in a GH Heater.

I can't afford to spend much money, job issues, but I don't want something that isn't reliable and will break quickly (I know Im asking a lot lol) Currently there is no power access in my GH or outdoors so if I went for an electric one the lead would have to fed from my conservatory somehow, but that isn't too far away as I only live in a small semi detached rental! 
I was wondering if anyone could recommend a certain brand, electric or paraffin that they think would be worth the money? There are so many on the market so it'd be good to hear your opinions image

Thanks in advance.


  • Busy-LizzieBusy-Lizzie Posts: 15,096

    For some years I had a paraffin heater with 2 chimneys. There was no electricity to the GH. It wasn't really big enough for my GH but it kept the frost out. It was a bit of a fiddle as it's roof part kept wanting to fall off it and you had to make sure there was enough paraffin and the wick was OK. Then one morning the GH was black with soot. Something had gone wrong with the heater and I couldn't get it working properly again. Not easy to clean it all up.

    Then I met 2nd OH and he fixed up electricity from the garage to the GH and gave me his old electric heater. It's so clean and easy. It's not very big and I don't know if it's still on the market. It isn't powerful enough to make the GH warm when it's below zero but it keeps it at 2 - 3° on freezing nights.

    I hope that helps, maybe someone else will be able to help with brands.

    Dordogne and Norfolk
  • pansyfacepansyface PEAK DISTRICT DerbyshirePosts: 17,781

    I have a paraffin heater which is described as being for a cold frame. It works perfectly well in my 8x6 greenhouse and keeps it frost free. Quite cheap to buy, it looks like a larger version of one of those old camping stoves, has a simple wick and a flat net grille over the flame (no chimney). It runs all winter during the nights and colder days on less than five litres of paraffin. Very simple to operate, just turn a little wheel every once in a while to extend the wick by a few millimeters.

    Don't know why B-L's went all smoky - mine has always behaved impeccablyimage

    Apophthegm -  a big word for a small thought.
  • My paraffin heater has never given me problems. Thermostatically controlled electric fan heaters are best. The thermostat means that it  only comes on when it reaches a certain temperature. That means it is cheaper to run than anything else. A paraffin heater you need to put on and off when cold. My Greenhouse is too far from the house to make it economical to add electricity to.

  • Pete.8Pete.8 Billericay, EssexPosts: 6,171

    I have one of these for 4-5yrs now- 

    I just use it to keep the frost out, then warm it a little early in spring

    There's a heater calculator here-

    I put some figures in roughly equivalent to your g/house and got the following- 


    which indicates around 1000W will keep it just above freezing



    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Thanks for all the replies, they're definitely a help image

  • I have an 8x6 alminimum glasshouse, with apex roof about 8 FT in height.

      My I suggest that you bubble wrap your greenhouse. I don't go completely up to the apex but cross from one side to other around halfway up, so less space to heat. A few years back I tried the following suggestion! which was even better as far as I'm concerned.

    Place one layer of double sided bubble wrap directly against the glass held in place by the plastic fittings you can purchase from garden centre. Then add a second layer attached to the end of the fitting in the correct way. Now you have a double skinned glasshouse. Haven't used a heater now for three years, nor lost any plants. 

     Only expense is initial purchase of bubble wrap, so if you are carefull removing the tape as and where you join sections together, which can last several years with careful use, sticky waterproof tape (yearly purchase)

    i also use a marker pen when removing the bubble wrap in spring, where each piece is fitted, so then no need to cut to fit next year.

    Many years ago did have a parrifin heater, but found the glasshouse was full of condensation each morning, so always opened the doors to try and dry out. Don't know if they are better now though, so my comment is just my view.

     Have an electric heater now, as have laid electricity laid to the glasshouse, used in conjunction with a timer unit, when it is required. Then one can set up the time to switch on and off, saving you a walk up each night. 



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