To start this section, I must first include a health and safety notice. Gas is dangerous. It has a number of interesting ways in which it can kill us. If you are in any doubt as to your knowledge or ability, do not fit, fix or change anything involving gas. Where buildings are concerned, there is a law stating only Gas Safe registered engineers can work on gas installations. It is different with caravans, as the requirement is merely to be 'competent'. This is to enable owners to renew the flexible pipe connecting the gas bottle the system. However, we all know there are different interpretations of competency. Even Gas Safe registered engineers need a specific LPG certificate (not all have this) to work on caravans. You have been warned.
The gas used in caravans is liquid petroleum gas (LPG) and there are two common forms: butane and propane. Butane burns hotter, but can freeze if winter temperatures drop low enough. I didn't want to remove the gas bottle every winter to store it inside, so we opted for propane. They operate at different pressures, so a gas specific regulator is required, and these are colour coded to the gas bottles; blue for butane and red for propane.
The original gas system on the Viking included gas lamps, a fridge, hob and grille, and fittings for a heater. We planned to use LED lighting, change the fridge, and add an oven. The gas supply pipe had several joints and connectors for its appliances, and had been open at the supply end for who knows how long? The chances of having dirt or insects in the pipe were high, plus there were now several redundant branches, so it was all removed to be replaced by new.
8mm copper pipe was used, in one continuous run, from the A-frame to the kitchen. It was routed under the caravan, through the holes in the wooden cross members that the original pipe used. In between, it was fixed with rubber lined, stainless steel P-clips. Having no joints in the pipe reduces the chance of a leak. The only joints will be at the connections with the manifold and at each of the three appliances (fridge, oven and hob).
At the front end of the caravan, a part sometimes known as a Fulham nozzle was fitted to the gas pipe, to connect a flexible rubber hose from the gas bottle. The date of manufacture is printed on the hose, and it is strongly recommended this should never be more than five years old. The hose is connected to the gas bottle with a regulator. We bought one with a gauge to make it easier to tell how much gas we have left.
The oven and fridge were both tested on gas when we bought them. Both worked and produced an even blue flame. We had never tried our hob and grill though, so that was next. Better late than never. This is a Flavel unit, fitted to the stainless steel sink/drainer/hob, and was original equipment on our Viking. The two burners would not light all the way round, and the grille lit but then went out. Not a good sign. The grille and both crowns on the burners were very rusty. The gas unit is fixed to the stainless combi unit by bolts going from below, up through the crowns and into the flame caps of the burners. One of these bolts snapped on trying to undo it. We were concerned that cleaning rust from the gas unit would result in debris getting inside the pipes, which at a later date could block the jets or cause some other dangerous situation.
Partially dismantled hob showing poor condition.
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| 'New' hob as received |
Lou really wanted to keep the original stainless steel kitchen unit, so we had to find a replacement hob and grille to fit. The holes for the burners are nine inches from centre to centre, but the burners on all the new camping stoves we looked at were further apart, so we couldn't make a new unit fit our kitchen. We spotted a Flavel Vanessa hob & grille on e-bay which looked clean (read 'not rusty') and Lou won the auction.
The 'new' hob was delivered the following week and was immediately tested. Both burners and the grille gave nice steady blue flames. However, it was a slightly different model from our original, so although the burners were still 9 inches apart, the flame caps were a little larger and would not fit through the holes in the stainless steel top. We reckoned the holes could be made larger to accommodate the bigger flame caps, but that would be another job for Ozzy at Shed Engineering, along with fabricating a new fridge flue for the wider fridge to vent through the original hole in the body.
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| Fridge flue on left & outlet on right no longer line up. |
Being aware of our deadline for Twinwood, Oz came up trumps with the modifications, turning the job around in a day. He supplied plumbing fittings to be cut to size for the flue, and used a die grinder to enlarge the holes in the stainless steel combi kitchen unit.
The gas pipe under the caravan was routed up through the floor inside the kitchen unit, and connected to a manifold. This splits the supply to the three different appliances, and each branch can be isolated by a tap. A hole for a gas drop was cut in the floor near the manifold and covered with a grille to keep insects out. LPG is heavier than air, so if there is a leak, the gas will fall out through the hole.
The copper pipe is bent by hand using a spring tube bender; an inexpensive device that prevents the pipe from kinking. A mini tube cutter was used to cut the pipe. It gives a clean, straight cut which is important for a gas tight seal. Connections are made with a compression fitting and olive. See this website for further useful information
http://www.thomson-caravans.co.uk/advice/diyprojects/gascompressionfitting.htm All joints are checked by spraying a washing-up liquid solution on them, then turning the gas on at the bottle. If the joint is not gas tight, the solution will bubble as gas escapes.
The gas supply pipe was run from the manifold to the fridge and connected. The original gas drop for the fridge had already been moved further back, but not too near the flame for it to blow out. Oz's flue components were cut to length and then sealed with car exhaust assembly paste.
Whilst assembling the fridge flue, I realised it wouldn't be possible in future to remove it in order to service the fridge, so an access panel was cut in the wall between it and the closet, which will be hidden from view under the basin in the closet. Now, via the access panel, we can undo the retaining screw and lift the flue top from the pipe, then slide the fridge out. There is sufficient flex in the copper supply pipe to slide the fridge out until the connection can be undone, if needed.
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| Access panel in closet |
Next to be connected was the hob. Again, the gas supply pipe ran from the manifold and was connected to the hob unit with a compression fitting. There were a couple of mounting holes in the base of the hob which were used to secure it in place.
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| Oven installed. |
The oven was inserted into the housing before connecting the gas supply to it. A couple of screws hold the oven in place, preventing it sliding about.
For ongoing safety, we have fitted a battery powered carbon monoxide detector, and a smoke detector in the caravan.
Being aware of our deadline for Twinwood, Oz came up trumps with the modifications, turning the job around in a day. He supplied plumbing fittings to be cut to size for the flue, and used a die grinder to enlarge the holes in the stainless steel combi kitchen unit.
Whilst assembling the fridge flue, I realised it wouldn't be possible in future to remove it in order to service the fridge, so an access panel was cut in the wall between it and the closet, which will be hidden from view under the basin in the closet. Now, via the access panel, we can undo the retaining screw and lift the flue top from the pipe, then slide the fridge out. There is sufficient flex in the copper supply pipe to slide the fridge out until the connection can be undone, if needed.
The gas pipe under the caravan was routed up through the floor inside the kitchen unit, and connected to a manifold. This splits the supply to the three different appliances, and each branch can be isolated by a tap. A hole for a gas drop was cut in the floor near the manifold and covered with a grille to keep insects out. LPG is heavier than air, so if there is a leak, the gas will fall out through the hole.
