I've had trouble this last week keeping the 6'8' greenhouse above freezing with the two burner paraffin heater I use and if it's anything like last year, no-one locally has any in stock once it gets cold.
The greenhouse ids full of geranium, Fuchsia and various other cuttings for next years hanging baskets.
In the garage we've had an old Super Ser stood that we'd never used but never got around to throwing it out.
Last Monday we bought a 15k bottle of Calor gas for it and put it in the greenhouse.
It's been of for about 18 hours per day for the last seven days.
This morning at AM it had gone out and wouldn't relight.
Has the gas frozen or would it have used it that quickly using only one burner on the minimum setting?
If, as I suspect, the gas has frozen, why would it do that when the heat was already on.
I can fully understand that if it refused to light, but I'm confused at the moment as to how to get round this problem.
Pat
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Pat - NOT being patronising! I thoguht my screenwashers had failed the other day! They hadn't, the bottle was empty! I know nothing about gas consumption but might 130 hours use have emtied your gas bottle? I didn't know they could freeze, lots of people use bottled gas, with the bottles outside, for heating, apparently without problems SFAIK,
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We have BP Lite bottles in the caravan and they last forever.
But that is summer, and we never cook on holiday so that could be why!
£32 for 130 hours...ouch!
Any good electricians out there?
Pat
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>> £32 for 130 hours...ouch!
we get three young plants for a quid at a local nursery.
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Yes, but you don't get any pleasure from nurturing and growing them yourself.
Pat
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I have something similar in Iffy Towers.
Suppliers quote around 100 hours for a gas bottle.
It's done well to last as long as it has.
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The L in LPG stands for Liquid :) ... shake the bottle!
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'Scuse me for stating the obvious Dog, but if it's frozen it won't be liquid.
Pat
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Calor gas is mainly propane which has a freezing point of -42°C. Butane has a freezing point of -0.5°C. Have you really got Calor gas or is it some other make and composition?
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It's in a blue Calor gas bottle with butane on it.
Pat
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>> It's in a blue Calor gas bottle with butane on it.
>>
>> Pat
>>
There's your answer. As I said, butane freezes at -0.5°C. You need a red bottle which is propane and which freezes at -42°C.
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...You need a red bottle which is propane and which freezes at -42°C...
Steady on.
Propane burns much hotter and can melt the burners in portable heaters designed to run on butane.
The connectors are different so the two are not interchangeable.
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dont you just change the regulator?
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...dont you just change the regulator?...
Yes you can, but as I said the Super Ser is designed to run at butane temperatures.
Running it on propane can melt/distort the burner itself.
People have had similar problems with cookers in touring caravans.
The temptation is to run propane because it burns hotter and because, as Les says, it's less inclined to freeze.
Last edited by: Iffy on Tue 21 Dec 10 at 10:01
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>> Propane burns much hotter and can melt the burners in portable heaters designed to run on butane.
>> The connectors are different so the two are not interchangeable.
In that case Pat is stuck with the butane freezing in this cold weather.
Last edited by: L'escargot on Tue 21 Dec 10 at 09:59
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This is why I'm confused though L'es, the heater was on last night at 7pm and the temperature in the greenhouse was around 48 degrees F.
The night before was colder and the temperature didn't go below 40F degrees so why would it freeze in these temperatures?
Pat
Last edited by: pda on Tue 21 Dec 10 at 10:03
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>> This is why I'm confused though L'es, .....
I'm sorry Pat, but the limit of my knowledge on this subject is the freezing point of butane and propane.
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Why doesn`t she get some largish cardboard boxes, fill with hay/straw (bales are fairly cheap off nice farmers) and snuggle her "valubles" into them and seal them. Thats what i`ve done with my "special things" inc my friends Tortoise!, and if its good enough for "shelly" its good enough for Geraniums!
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Would the latent heat of evaporation cause it to freeze at a higher temperature? As the gas expands in the bottle and evaporates it lowers its temperature.
Look at the gas bottles on road laying and line painting vehicles. The frost line on the bottle indicates the level of liquid inside, so I'm led to believe.
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>> Would the latent heat of evaporation cause it to freeze at a higher temperature? As
>> the gas expands in the bottle and evaporates it lowers its temperature.
I wanted to say that myself but couldn't think how to word it.
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...The frost line on the bottle indicates the level of liquid inside, so I'm led to believe...
It does, same happens at the caravan.
You can buy stick-on 'gauges' for gas bottles, but I don't know how they work.
www.caravanaccessoryshop.co.uk/index.php?_a=viewProd&productId=402
The above site also has an in-line gauge.
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>>Would the latent heat of evaporation cause it to freeze at a higher temperature?
Thinking about it, I don't reckon it will freeze to a solid. Below a certain temperature the liquid won't evaporate to a gas, therefore the contents of the bottle would be a liquid at atmospheric pressure. Atmospheric pressure inside the bottle means there's nothing to push it out.
Any physics experts on Boyle's (and others) laws, adiabatic and isothermal changes?
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When Butane gas expands and burns, the liquid cools. So if the heater is thermostatically controlled - it burns more as the temperature falls - the gas cylinder gets colder.
If the cylinder is on the ground .. and hot air rises.. the heat will never keep the cylinder warm enough... unless the heater is a radiant one and some of the heat goes towards the bottle.
(Been there, done it, can't afford to heat a greenhouse in our winter ).
A Blue Flame paraffin heater is better - but it burns at least 4 litres in 3 days (£5 +) ..
You can partition off your greenhouse and only heat a small section... but in these temperatures you are wasting your time.
I gave up trying to overwinter geraniums.. a 3 month cycle of heating a greenhouse would cost at least £120... better to buy young plants and heat in spring for a month.. (which you would have to do in addition to the winter heating for overwintered plants..)
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The bottle would appear to be empty as I went and lit it but checked 10 minutes later and it had gone out again.
Early indications are that I have lost at least 100 Geranium cuttings but the Fuchsias appeared to have fared better but only time will tell.
I know that in simple economic terms it isn't possible to justify heating it but what price do you put on the pleasure gained from having a winter hobby, a place to bolt to that is my domain and the ability to sow seeds in January for next summer.
It really is the same as you guys with your centrally heated, carpeted garages, you know:)
Pat
Last edited by: pda on Tue 21 Dec 10 at 16:52
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>> what price do you put on the pleasure gained from having a winter hobby, a
>> place to bolt to that is my domain and the ability to sow seeds in
>> January for next summer.
Us lads used to call it "down the disco"
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>> It really is the same as you guys with your centrally heated, carpeted garages, you
>> know:)
>>
>> Pat
>>
I know I've said that our integral garage is heated as part of the central heating, but how did you know it was carpeted? Actually it's only on the right and at the front of where the car goes.
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I bet there's a few beers hidden somewhere too:)
Pat
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My garage is double glazed.
I couldn't be bothered with painting window frames and it didn't seem possible to get single glazed UPVC frames when it was built.
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So is my greenhouse....with bubblewrap!
Pat
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>> It really is the same as you guys with your centrally heated, carpeted garages, you
>> know:)
Shag pile of course..:))
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>> Would the latent heat of evaporation cause it to freeze at a higher temperature? As
>> the gas expands in the bottle and evaporates it lowers its temperature.
>>
Spot on. I've actually seen propane refuse to gas properly at about -10C ambient when running a very high powered space heater in a tent (the bottle was outside - mistake).
It doesn't 'freeze' of course, it just refuses to boil i.e. vapourise. It's not the freezing point of propane that's -42C, or for butane --0.5C, it's the boiling point.
The flame temperature of butane and propane is actually very similar. But butane has a higher energy content - so if used with a propane appliance at the same pressure, more heat will be generated. I have just binned a propane hotplate that was used with butane and melted the burners!
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We have an LPG cooker which runs on propane. If the temperature drops much below minus 8, the supply stops cos the regulator freezes. Propane might freeze at minus 42 but it sure as hell don't flow at minus 8!
Brand of gas is irrelevant IMO. I agree with other posters, Pat, it's run out. Also agree about paraffin heaters; my late father always used them in his greenhouse.
Last edited by: Harleyman on Tue 21 Dec 10 at 19:33
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Pat,
Does your greenhouse have concrete floor or is it (like mine) compost/earth? If latter (and soil is reasonably dry), you can bury your cuttings and they will survive winter. Frost rarely penetrates more than 3/4 inches into ground even in harshest winter. Otherwise, Devonite's suggestion above is good - or even just a good covering of straw/hay over top of pots will protect from frost. Have a little dig in your garden and see how little frost penetrates ground.
(I think I might be trying to teach my grandmother (no offense, honest!!) to suck eggs - but I mean well!!) And straw is cheaper than gas/paraffin!!
Phil
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It does have soil floor with a paving path down the middle.
I know I can bury them, and have done so in years gone by, but I love to tend them in the long winter months.
I like to to take cuttings and get them started well before the winter sets in so I can keep them short and stocky.
I salvage cuttings of Verbena, Petunia and all the other trailing plants before the summer ends. Next years new Sweet Pea plants are in there along with Begonia corms and lot of Lilies.
It is absolutely full up with extra shelving added to make enough room!
I don't throw anything away if there is a chance it will survive the winter.
I think the way to go is to get electricity in there for next year.
We already have it outside for the pond pumps and lighting so it shouldn't be too difficult and it would be nice to have a light in the garage as well.
I'm finding it difficult to maintain the paraffin heater this winter when it's cold and fingers won't do what I want them to. It is almost impossible to get those silly tops off a can of paraffin anyway, just as it is with bleach bottles (and pill bottles). Turning the wicks up and down is another awkward thing to do and I have to use a pair of pliers to do it, or ask for help which is a backward step.
I asked the postman ( we do live in a village!) to get the lid off a new can of paraffin the other day and he couldn't get it off either.
Pat
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Super Ser - Perky Penguin
