Diesel heaters

Unless it has multiple elements and one has burnt out I cant see how it could run at less that the 2Kw stated. I used to use a couple of old Parwin heaters and you could actually remove some elements on those.

I now have a 2.5Kw in my 14x6 greenhouse and a 2Kw in my 8x6, they both seem to be ok at keeping the frost out and I could turn the thermostats higher, but it would cost a lot more.

 

I have a parrafin heater which I couldn't use because my largest greenhouse is only 6' x 8' and as @shiney I had to leave a vent open because even on it's lowest setting, it heated the place to over 100f or nearly 40c. A total waste of fuel. And I didn't want to roast the plants.

That heater looks fab. If I'd have seen one of those before getting my mains gas heater, I would have tried it first.

 

These videos are quite good. The only thing I think the two fellows missed is a great opportunity to use the exhaust as additional heating. Run the fumes through long tubing either coiled or run the length of the greenhouse before exiting the greenhouse. Even burying tubing for the exhaust would produce nice "floor" heating.

Thank you for posting these!

 

I did think similar regarding the exhaust when one of them said it gets pretty hot, but I was assuming you cant go above a certain length before it becomes ineffective as an actual exhaust in taking the gasses away.

 

My old paraffin heaters were almost useless regarding heat output, but the vent open is to bring in fresh oxygen and prevent a build up of fumes.

I cant image what kind you had that got the temperature up to 100F.

 

It was the smallest I could find at the time. 10k btu I believe. I might go down to the cellar and look at the box.

10.5k Btu and a tank capacity of 1.1 gallons or about 5 liters

 

I only used the old yellow flame types in the greenhouse, frost protection only, I know the blue flame ones were better as they were often used in the house over here in the 50s and 60s.
I've seen paraffin on sale at £7plus for 4 litres these days, I used to get 4 gallons for five bob back then.

That's real gallons not those funny US ones.

 

@pete I think it has 2 elements, so it's probably down to 1kW! My supposedly more robust one that I bought after this is also running on half I think, and the fan clanks a lot!
Sorry to divert the thread, but does anyone recommend any electric ones? I know about Hotbox but they're pricey.
I also used to use paraffin as backup, but it became so expensive. Also the lack of thermostatic controls...

 

I use the ones from screwfix, mostly workshop heaters greenhouse heaters are a rip off IMO.
I dont have this make but its very similar to one of mine, but I use a separate thermostat.
https://www.screwfix.com/p/erbauer-portable-ptc-workshop-heater-2500w/639fv

Lots on Amazon.

 

Yes, this big old parrafin one is a yellow flame. A 3.78L (one gallon) jug costs about double what it is over there.

The one I had to fix this last summer in prep for this spring, is a blue flame natural gas one. It's quite good at keeping the greenhouse above freezing and could heat it up to bikini time but obviously hot would be expensive. It doesn't need an exhaust either.

I have a small electric heater that works too but electricity is deadly expensive. So that is the last resort.

 

Those little diesel ones would be perfect for my smaller greenhouses and I already have dc wires from a battery array which as you know is down in my cellar and those are powered by solar panels so zero cost for the spark. The price of diesel for how much those use is quite good.

I think I'll save up for a couple of those What a great topic/thread!!

 

Its strange how we are all being steered towards electric when its probably the most expensive energy on the planet.

 

Or solar, when some of us live in the cloudiest part of the world!

Thanks for link @pete - yes I use the Inkbird controller, as I find the ones inbuilt on heaters pretty random.