Gas Fittings Help!

[Ronan]

Hi guys.
Im new to Gas and My new Bailey pursuit seems to have gas fittings for a 4.5kg blue gas bottle but in my haste I bought a 7kg bottle. So i have no idea what regulator or hose to use etc. Can anyone help please?

I have photos but can't seem to attach.

Thanks

 

[Craigyoung]

Try this simple method....

https://www.practicalcaravan.com/forum/our-website/56475-posting-pictures#453457

 

[ProfJohnL]

Hi guys.
Im new to Gas and My new Bailey pursuit seems to have gas fittings for a 4.5kg blue gas bottle but in my haste I bought a 7kg bottle. So i have no idea what regulator or hose to use etc. Can anyone help please?

I have photos but can't seem to attach.

Thanks

Hello Ronan,

A lot will depend on what Gas supply pressure your caravan is designed to take. Older caravans used to use 37mBar for Propane, and 28mBar for Butane. each gas bottle required its own regulator, and you could not mix them up because the fittings were different. More recent caravans have a universal 30mBar regulator and will accept either Butane or Propane, but you do need to have teh correct "pigtail" to connect to the gas bottle.

Your caravan supplier should carry the necessary parts or be able to obtain them.

BUT you may have another problem, becasue the 7kg bottle is a physically different size and may not fit in the gas locker correctly. You MUST store, carry and use gas bottles the right way up, and the must be secured so they cannot fall over. if the 7kg cannot be secured properly, you should change it for one of the correct size.

 

[Hutch]

Hi It sound like you had a 4.5 kg butane, gas bottle and have possible bought a 6kg red propane gas bottle the Fittings to the bottles are different, the Red calor gas bottles and other s have a left hand "tightening " thread. To really understand , go to a caravan dealer and they should be more than welcome to help. .

 

[Dustydog]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

 

[Damian]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

I have no idea, but then I also do not know why the chicken crossed the road !! :evil:

 

[Dustydog]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

I have no idea, but then I also do not know why the chicken crossed the road !! :evil:

 

[ProfJohnL]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

Its becasue its no to do with the calorific value which is a measure of how much heat a quantity of gas can produce, its the specific gravity of the liquified gas per unit volume. Butane has a higher specific gravity compared to Propane, so for the same volume of liquified gas butane will weigh more.

It also means that you will get a longer burn time from a bottle of Butane which will last nearly 12% longer than the same size of Propane.

 

[Buckman]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

Its becasue its no to do with the calorific value which is a measure of how much heat a quantity of gas can produce, its the specific gravity of the liquified gas per unit volume. Butane has a higher specific gravity compared to Propane, so for the same volume of liquified gas butane will weigh more.

It also means that you will get a longer burn time from a bottle of Butane which will last nearly 12% longer than the same size of Propane.

Thanks a very interesting reply. Would this account for why Butane is supposed to burn hotter than propane? I have no idea as only use Butane for our gas heater at home.

 

[ProfJohnL]

Why are the butane and propane gas bottles identical in size yet the former gives me 7kgs and the latter 6kgs? Weird when you consider the calorific value of butane is greater than propane. hmy:

Its becasue its no to do with the calorific value which is a measure of how much heat a quantity of gas can produce, its the specific gravity of the liquified gas per unit volume. Butane has a higher specific gravity compared to Propane, so for the same volume of liquified gas butane will weigh more.

It also means that you will get a longer burn time from a bottle of Butane which will last nearly 12% longer than the same size of Propane.

Thanks a very interesting reply. Would this account for why Butane is supposed to burn hotter than propane? I have no idea as only use Butane for our gas heater at home.

The temperature of a Butane flame in air is 1970C and a Propane is 1980C, that is less that's a 0.5% difference so its unlikely any normal person could detect a practical difference in flame temperature.

However through a combination of other characteristics (including flame speed, vapour densities, energy densities and supply pressure of the gasses which all contribute to the Wobbe index number for each gas) a burner using Butane will release slightly more heat (not temperature) than the same burner using Propane, if the gas is supplied at the same pressure.

The modern LPG gas pressure of 30mBar in caravans will mean that a burner may provide more heat on Butane than Propane. You might notice a difference is boiling a kettle or saucepan, or starting your heating from cold, but if the appliance uses thermostatic control, the thermostat will mask the difference in heat release.

With the older 28mBar for Butane and 37mBar for Propane systems teh supply pressure largely evens out the the heating difference.

Cabinet heaters like the one you probably own are specifically designed for use with Butane gas Some use a dedicated design of clip on regulator that will only fit special heater gas bottles. This is more to do with the fact the heaters are designed to be "safe" to use indoors, and the advice is that propane should only be stored and used outdoors or where extensive external ventilation of the gas store is provided.

 

[Anseo]

The temperature of a Butane flame in air is 1970C and a Propane is 1980C, that is less that's a 0.5% difference so its unlikely any normal person could detect a practical difference in flame temperature.

However through a combination of other characteristics (including flame speed, vapour densities, energy densities and supply pressure of the gasses which all contribute to the Wobbe index number for each gas) a burner using Butane will release slightly more heat (not temperature) than the same burner using Propane, if the gas is supplied at the same pressure.

The modern LPG gas pressure of 30mBar in caravans will mean that a burner may provide more heat on Butane than Propane. You might notice a difference is boiling a kettle or saucepan, or starting your heating from cold, but if the appliance uses thermostatic control, the thermostat will mask the difference in heat release.

With the older 28mBar for Butane and 37mBar for Propane systems teh supply pressure largely evens out the the heating difference.

Cabinet heaters like the one you probably own are specifically designed for use with Butane gas Some use a dedicated design of clip on regulator that will only fit special heater gas bottles. This is more to do with the fact the heaters are designed to be "safe" to use indoors, and the advice is that propane should only be stored and used outdoors or where extensive external ventilation of the gas store is provided.

Of course I knew that already :silly:

I remain befuddled as to why you can have more heat but not an increase in temperature :blink:

Perhaps the Prof can take time to explain, ta Prof.

 

[Anseo]

OOPS, my bad

 

[ProfJohnL]

I remain befuddled as to why you can have more heat but not an increase in temperature :blink:

Perhaps the Prof can take time to explain, ta Prof.

Take one hairdryer it will produce a volume of air at a given temperature, Take a second identical one, you now have twice the volume of air but at the same temperature - = twice as much heat energy but no increase in temperature. Butane will produce a more dense flame (that does not mean bigger or hotter) than propane.
Its a complex set of parameters, and I'm out of practice at doing the calculations, but you do get more heat from butane if all other factors are the same.

 

[Anseo]

I remain befuddled as to why you can have more heat but not an increase in temperature :blink:

Perhaps the Prof can take time to explain, ta Prof.

Take one hairdryer it will produce a volume of air at a given temperature, Take a second identical one, you now have twice the volume of air but at the same temperature - = twice as much heat energy but no increase in temperature. Butane will produce a more dense flame (that does not mean bigger or hotter) than propane.
Its a complex set of parameters, and I'm out of practice at doing the calculations, but you do get more heat from butane if all other factors are the same.

Thank you Prof.

If I place a blown air fan heater in a room space, would I not expect the room to be warmer if I doubled or trebled the number of equivalent poweredoutput devices in the same room?

Or would the roomspace only achieve the maximum temperature output of a single fan heater, albeit more quickly?

I am not disputing what you say, just trying to become a little more enlightened on the subject matter.

Ta Prof

 

[Dustydog]

So in theory running my Trumatic fire on 1000watts should give me the same maximum temperature as 2000watts hmy: That is two 1000 watt hair dryers.
Lost on me :S :silly:

 

[NigelHutson]

Ronan,

To get back to the original question.

Can I assume that your gas bottle is a Calor and blue in colour (butane)? If so, you will have a screw on connector for the 4.5kg bottle, whereas the 7kg will require a push/clip on connection. Any caravan dealership will have a good stock of connections and will be able to help.