trevskoda
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I think when folks can splash out hugh sums of lolly for a van then a derv cooker price will be low down there list.
Diesel Heater
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Nabsim
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There are a lot more folk in vans that only have a small amount of money for a van than there are those with huge amounts Trev. Thousands use a van to live in, possibly tens of thousands or more. They need practical solutions not £1500+ diesel cookers
trevskoda
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Maybe you are right,maybe not,i have seen many on old scrap boats,maybe next time i shall grab one or two.There are a lot more folk in vans that only have a small amount of money for a van than there are those with huge amounts Trev. Thousands use a van to live in, possibly tens of thousands or more. They need practical solutions not £1500+ diesel cookers
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mistericeman
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Ha ha Trev, I remember paraffin heaters inside and the tiger tails and Esso Blue adverts. Pre H&S of course but worked a treat
And the smell/condensation.....
As a kid at the grandparents 'my' bedroom was warmed by a parrafin bowl heater....
Awful thing looking back now.... Thank god things have moved on.
Mind I still have a love of petrol/parrafin stoves etc...
Including my ex British military No1 trench cooker... 2 gallons of petrol under pressure with a flame at the front of it... What's, not to like?
Sharpie
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I don't think a diesel hob would suit me. You get one low powered ring, together with a warming area beside it. Some have a top that you can close and turn it into a small air heater as well, but it's at the wrong level, you want your hot air vents at floor level so that the heat has a chance to rise around the van. Same slow start-up and shutdown as an Eberspacher/Webasto/Chinese air heater, with heavy current consumption during start up and shutdown. Not easily "off and on-able". Actually they operate the same way, just that the burner heats the (fragile ?) ceramic top instead of an air heat exchanger.
If you have any interest in cooking, gas is the best way IMO. At least a two burner stove. If only using gas for cooking it doesn't take much. If you have the electrical power, induction is even better.
Gas hobs are as simple as it gets. Diesel hobs are complicated, moving parts, electronics, controllers, electrical power demand, slow start up and shut down, noisy, exhaust, and combustion air to be routed externally, wiring and so on. I suspect that they are subject to the same maintenance/reliability issues as the simpler air heaters, but more difficult to access, probably have to take out the whole hob first.
I understand that elsewhere in the EU gas installs in vans have to be professionally done and annually inspected. Certainly mine (German) came with an official external sticker declaring it good, for a year. Seems we don't have such rules in the UK. One of the selling points of the Wallas is that it is not subject to such inspection and is designed for DIY fitting. Over a few years that could justify the initial cost, in other territories. Also some mention of parking restrictions there if having gas fired appliances.
Does everyone turn off their gas at the cylinder before setting off ? Even just switching the fridge off gas. Then visiting a filling station whilst the open flame is burning just behind the external vents. My fridge is manual, you have to remember to do this. And to spark it up again when you stop.
www.wallas.fi
If you have any interest in cooking, gas is the best way IMO. At least a two burner stove. If only using gas for cooking it doesn't take much. If you have the electrical power, induction is even better.
Gas hobs are as simple as it gets. Diesel hobs are complicated, moving parts, electronics, controllers, electrical power demand, slow start up and shut down, noisy, exhaust, and combustion air to be routed externally, wiring and so on. I suspect that they are subject to the same maintenance/reliability issues as the simpler air heaters, but more difficult to access, probably have to take out the whole hob first.
I understand that elsewhere in the EU gas installs in vans have to be professionally done and annually inspected. Certainly mine (German) came with an official external sticker declaring it good, for a year. Seems we don't have such rules in the UK. One of the selling points of the Wallas is that it is not subject to such inspection and is designed for DIY fitting. Over a few years that could justify the initial cost, in other territories. Also some mention of parking restrictions there if having gas fired appliances.
Does everyone turn off their gas at the cylinder before setting off ? Even just switching the fridge off gas. Then visiting a filling station whilst the open flame is burning just behind the external vents. My fridge is manual, you have to remember to do this. And to spark it up again when you stop.
Boat heaters and stoves, cottage heaters and water heaters - Front page - Wallas
Environmentally friendly diesel boat heaters and stoves, camper van heaters and stoves, cottage air and water heaters for off-grid environments.
www.wallas.fi
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I seem to remember reading on Facebook that some Chinese heaters stamped with CE are not tested but simply China Export.
runnach
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The size of gas bottle lugged about by your roofer has nothing in a sense to do with the properties of propane . The properties remain the same whether stored in a 6 kg bottle or 47 kg bottle..I.e expansion rates flame temps lower and upper explosion limits etc
The problem is far simpler and applies to motorhomee too .... That problem is he has gas hungry appliance that is exceeding the take off rate of s smaller bottle. Assuming the regulator can cope , propane is stored as a liquid and vapour isle to a gas ...it does this by drawing heat from the skin of the bottle sometimes referred to as the wetted surface area , it figure a larger vessel provides a larger surface area so the gas vapourise more readily than a smaller bottle ..it's no more complicated than that .
The link re warming blankets seems like snake oil absolutely useless remember at -24 there is still heat and propane will still readily boil . By applying a blanket the bottle has difficulty drawing heat ( nor hoe butane keels I've when people mistakenly insulate.)
The problem is far simpler and applies to motorhomee too .... That problem is he has gas hungry appliance that is exceeding the take off rate of s smaller bottle. Assuming the regulator can cope , propane is stored as a liquid and vapour isle to a gas ...it does this by drawing heat from the skin of the bottle sometimes referred to as the wetted surface area , it figure a larger vessel provides a larger surface area so the gas vapourise more readily than a smaller bottle ..it's no more complicated than that .
The link re warming blankets seems like snake oil absolutely useless remember at -24 there is still heat and propane will still readily boil . By applying a blanket the bottle has difficulty drawing heat ( nor hoe butane keels I've when people mistakenly insulate.)
Sharpie
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Channa, it seems to me that you have an incomplete theoretical understanding. perhaps based on little practical experience.
My roofer was not an idiot, far from it, he had a good understanding of what it took to supply his kit and knew what actually worked, not just theoretical figures from the suppliers. If you believed that a 19kg cylinder would have been ample. Not so in reality.
At say -24 sure propane still boils. At a rate depending on the volume left in the cylinder. But as you draw off the gas the energy to boil it (latent heat of vaporisation) has to come from somewhere i.e. the air surrounding the cylinder. Otherwise that energy comes from the liquid itself cooling further. As the liquid gets colder and colder, the takeoff rate reduces. Quoted takeoff rates are for a full bottle, at a standard temperature, in free air.
As the temperature drops, so does the vapour pressure. E.g. at the standard temperature of 20C it is about 10 bar. Whereas at -20 it is less than 2 bar. That's absolute, so subtract 1 from that. 9 bar nominal, under 1 bar at -20.
You could probably translate that into take-off rate, eg. 1/10 the headline rate at -20. For a full bottle. In free air.
Also why propane cylinders are rated to 30 bar (with margin) and the valves fitted with pressure relief valves typically set at 26 bar. To withstand temperatures of about 60C. Well I've camped in temperatures well over 40C with the sun beating down on the van so hard you could almost fry an egg on the bonnet (I tried, it cooked the white but not the yolk). Goodness knows what the temperature inside the locker was. Fortunately I was using a Spanish butane cylinder having depleted my propane, so it wasn't a worry.
Also consider that, whilst your pigtails and connections may seem sound, the rubber pigtail in date (they degrade) when you checked them under 9 bar with leak detector spray or something more sophisticated,, they need to be good enough for three times that pressure, when the rubber tube could also be near 60C, to be safe. So always use the type with an excess flow valve at the cylinder end. Clip on valves sometimes have these inside, but if you are using e.g. a Calor cylinder with a basic twist valve there is no such safety device. If that pigtail blows out, or gets ripped off in an accident, well you can imagine what might happen with propane spewing out under several hundred psi..
See https://www.engineeringtoolbox.com/propane-vapor-pressure-d_1020.html
That should give you a feel for how drastically low, and high, temperatures affect propane.
The regulator is no obstacle in my setup.
Even in summer conditions my propane bottle develops hard frost at the level of the liquid with only 2kW draw from my Truma heater. The liquid must therefore be below zero, maybe a long way below zero. A big temperature differential. There is no air circulation inside the locker except possibly a little through the drop vents, it's basically an insulated coolbox surrounding the cylinder.
So the thermal path to gasfiy the liquid is external air > walls of locker > air inside locker > wall of cylinder > liquid propane. There is a temperature drop across each interface, adding up to a big differential. The bottle would perform much better if it was outside the locker, exposed to the outside air.
As the bottle empties there is also a smaller and smaller volume of liquid left. You just can't use this when it gets really cold.
If I had a 4 kW heater rather than my underpowered 2 kW one, the problem would be twice as bad.
This is the reality, not theoretical understanding.
Those electric heating blankets are not "snake oil", such an ignorant remark. They are used by people in genuinely cold climates who still like to operate e.g. big gas barbecues outside, drawing off many kW of gas. Or the big ones for household storage tanks.
I've worked in Minneapolis, Ottawa and Calgary in the depths of Winter and know what real prolonged cold is like. They manage just fine. some UK people may not have a clue what properly cold weather is, or how rapidly it can change. People there have to be prepared for it. We are blessed to have the Gulf Stream keeping us warm and moderating our temperate climate.
Zero degrees (F) is considered unseasonably warm. That's -18C to us. It gets much colder than that.
On a micro scale I know how to manage LPG in cold weather, even melting snow for water, that's why my backpacking stove is an expensive one that can take a feed of liquid gas from the inverted canister and boil it up in a preheater at the burner. It can also run off pressurised petrol, paraffin, diesel, even jet fuel, but I prefer to use gas canisters where possible on short trips.
Perhaps we could return to discussing diesel heaters now. I've identified some candidates that look good, but installation the way I want it is going to be complicated.
My roofer was not an idiot, far from it, he had a good understanding of what it took to supply his kit and knew what actually worked, not just theoretical figures from the suppliers. If you believed that a 19kg cylinder would have been ample. Not so in reality.
At say -24 sure propane still boils. At a rate depending on the volume left in the cylinder. But as you draw off the gas the energy to boil it (latent heat of vaporisation) has to come from somewhere i.e. the air surrounding the cylinder. Otherwise that energy comes from the liquid itself cooling further. As the liquid gets colder and colder, the takeoff rate reduces. Quoted takeoff rates are for a full bottle, at a standard temperature, in free air.
As the temperature drops, so does the vapour pressure. E.g. at the standard temperature of 20C it is about 10 bar. Whereas at -20 it is less than 2 bar. That's absolute, so subtract 1 from that. 9 bar nominal, under 1 bar at -20.
You could probably translate that into take-off rate, eg. 1/10 the headline rate at -20. For a full bottle. In free air.
Also why propane cylinders are rated to 30 bar (with margin) and the valves fitted with pressure relief valves typically set at 26 bar. To withstand temperatures of about 60C. Well I've camped in temperatures well over 40C with the sun beating down on the van so hard you could almost fry an egg on the bonnet (I tried, it cooked the white but not the yolk). Goodness knows what the temperature inside the locker was. Fortunately I was using a Spanish butane cylinder having depleted my propane, so it wasn't a worry.
Also consider that, whilst your pigtails and connections may seem sound, the rubber pigtail in date (they degrade) when you checked them under 9 bar with leak detector spray or something more sophisticated,, they need to be good enough for three times that pressure, when the rubber tube could also be near 60C, to be safe. So always use the type with an excess flow valve at the cylinder end. Clip on valves sometimes have these inside, but if you are using e.g. a Calor cylinder with a basic twist valve there is no such safety device. If that pigtail blows out, or gets ripped off in an accident, well you can imagine what might happen with propane spewing out under several hundred psi..
See https://www.engineeringtoolbox.com/propane-vapor-pressure-d_1020.html
That should give you a feel for how drastically low, and high, temperatures affect propane.
The regulator is no obstacle in my setup.
Even in summer conditions my propane bottle develops hard frost at the level of the liquid with only 2kW draw from my Truma heater. The liquid must therefore be below zero, maybe a long way below zero. A big temperature differential. There is no air circulation inside the locker except possibly a little through the drop vents, it's basically an insulated coolbox surrounding the cylinder.
So the thermal path to gasfiy the liquid is external air > walls of locker > air inside locker > wall of cylinder > liquid propane. There is a temperature drop across each interface, adding up to a big differential. The bottle would perform much better if it was outside the locker, exposed to the outside air.
As the bottle empties there is also a smaller and smaller volume of liquid left. You just can't use this when it gets really cold.
If I had a 4 kW heater rather than my underpowered 2 kW one, the problem would be twice as bad.
This is the reality, not theoretical understanding.
Those electric heating blankets are not "snake oil", such an ignorant remark. They are used by people in genuinely cold climates who still like to operate e.g. big gas barbecues outside, drawing off many kW of gas. Or the big ones for household storage tanks.
I've worked in Minneapolis, Ottawa and Calgary in the depths of Winter and know what real prolonged cold is like. They manage just fine. some UK people may not have a clue what properly cold weather is, or how rapidly it can change. People there have to be prepared for it. We are blessed to have the Gulf Stream keeping us warm and moderating our temperate climate.
Zero degrees (F) is considered unseasonably warm. That's -18C to us. It gets much colder than that.
On a micro scale I know how to manage LPG in cold weather, even melting snow for water, that's why my backpacking stove is an expensive one that can take a feed of liquid gas from the inverted canister and boil it up in a preheater at the burner. It can also run off pressurised petrol, paraffin, diesel, even jet fuel, but I prefer to use gas canisters where possible on short trips.
Perhaps we could return to discussing diesel heaters now. I've identified some candidates that look good, but installation the way I want it is going to be complicated.
Fazerloz
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It would seem to me that you have never been more wrong on any of your posts than you are about Channa. But you have tried hard.
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I must be missing a post from channa. Can't see him saying your roofer was a idiot or size of bottle to use. But I hope your roofer had his hearing protection in. Health and safety reasons
Sharpie
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Read carefully. Channa is polite and seems to know his stuff. My roofer is an educated man and understands the theory and what actually works in practice. Not what the suppliers say.
The same applies elsewhere in the real world, the theory is all well and good, but once you start stressing LPG installations in situations that suppliers may assure you will be fine, you may be disappointed. Just my experience.
The same applies elsewhere in the real world, the theory is all well and good, but once you start stressing LPG installations in situations that suppliers may assure you will be fine, you may be disappointed. Just my experience.
Fazerloz
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Unfortunately you either didn't read Channas post and understand it ,or just dismissed it because it didn't agree with your view, as you have done in my opinion on other posts and threads.
With that I will now bow out and leave you to educate the rest of the forum.