Some of you may have one of these units stuck up in the roof, mostly on older vans. They were once fetted as the closest you could get to an air-con, without actually having one. In actual fact they are an evaporation unit, using the MHs own water tank to supply water, which cools the air being sucked into the van. The main advantages over a real air-con unit are weight, and the fact that they only draw around 6 amps at 12 volts. Any decent solar panel will provide enough battery power to run one.
Having one stuck up on the roof of our Hymer, and finding that the water supply pump in the locker had been disconnected, I tried to find out some info, with a view to getting the thing up and running again. Information is very scarce, and apart from a Dutch sales document, and a shoddy PDF schematic, I could find nothing. So here goes.
The unit cover mounted on the roof is secured with 6 stainless self tappers. Be careful as you take it off, because underneath is a water supply pipe. Three more screws remove a spinner plate, which is in direct drive from the air fan motor. Now another four self tappers removes the filter cover. This can be removed complete with the large conical foam filter. Ours was bunged up solid with dirt, and so a good wash in the sink, followed by a drip-dry outside, whilst I carried on.
I found that the pump, mounted next to the fresh water tank, had been disconnected, and so, brave as anything, I re-connected, and waited for the flash. Nothing. :thumb:
Back up onto the roof to check the pipework, before attempting to switch on. The foam filter sits in what I can only describe as a plastic copy of a car tyre cut in half. In the bottom of this 'bowl', is a return pipe. The feed pipe, which attaches to a sprinkler situated directly over the spinner plate, I laid in the bottom of the 'bowl'. Now back inside, and flicked the switch. The pump throbbed, the water gurgled..........Up on top quick, in case a deluge would leak into the van, but no, just a healthy trickle......However, the bowl was just filling, with no return water going out. Switched off at once, and worked out that as the return pipe to the tank must act on a syphon system, unscrewed the water connecting plug from the tank, found the right pipe, and gave it a long blow. More gurgling noises. Onto the roof, to find that the return pipe must have been blocked, as a load of gunge had settled into the bowl. Clean that out, and try again. This time, the water returned to the tank, success!. Time for a brew.
Re-located the foam filter, filter cowl, and spreader plate. The supply pipe was very old, so took the opportunity to replace it. Pipe onto sprinkler, cover on, back inside. Now for the test. Started the pump, selected 'cold', brought in the circulating fan, and waited. With a couple of minuets, the cool air was powering in. Within fifteen minuets, the inside temperature had dropped four degrees! Checked everywhere for leaks, nothing.
People, for some reason, are 'scared' of these things. Well, the chance of water flooding into your van is not a merry thought. They are really easy to service. If anyone has one, I would be more then willing to talk them through a strip down and clean. Parts can be sourced from Cak-Tanks. I can only think that ours had been disconnected because of the blocked return pipe. oh: Dutch PDF doc and schematic on link below.
Dave.
http://www.freiko.nl/PDF/72836-nl.pdf
Having one stuck up on the roof of our Hymer, and finding that the water supply pump in the locker had been disconnected, I tried to find out some info, with a view to getting the thing up and running again. Information is very scarce, and apart from a Dutch sales document, and a shoddy PDF schematic, I could find nothing. So here goes.
The unit cover mounted on the roof is secured with 6 stainless self tappers. Be careful as you take it off, because underneath is a water supply pipe. Three more screws remove a spinner plate, which is in direct drive from the air fan motor. Now another four self tappers removes the filter cover. This can be removed complete with the large conical foam filter. Ours was bunged up solid with dirt, and so a good wash in the sink, followed by a drip-dry outside, whilst I carried on.
I found that the pump, mounted next to the fresh water tank, had been disconnected, and so, brave as anything, I re-connected, and waited for the flash. Nothing. :thumb:
Back up onto the roof to check the pipework, before attempting to switch on. The foam filter sits in what I can only describe as a plastic copy of a car tyre cut in half. In the bottom of this 'bowl', is a return pipe. The feed pipe, which attaches to a sprinkler situated directly over the spinner plate, I laid in the bottom of the 'bowl'. Now back inside, and flicked the switch. The pump throbbed, the water gurgled..........Up on top quick, in case a deluge would leak into the van, but no, just a healthy trickle......However, the bowl was just filling, with no return water going out. Switched off at once, and worked out that as the return pipe to the tank must act on a syphon system, unscrewed the water connecting plug from the tank, found the right pipe, and gave it a long blow. More gurgling noises. Onto the roof, to find that the return pipe must have been blocked, as a load of gunge had settled into the bowl. Clean that out, and try again. This time, the water returned to the tank, success!. Time for a brew.
Re-located the foam filter, filter cowl, and spreader plate. The supply pipe was very old, so took the opportunity to replace it. Pipe onto sprinkler, cover on, back inside. Now for the test. Started the pump, selected 'cold', brought in the circulating fan, and waited. With a couple of minuets, the cool air was powering in. Within fifteen minuets, the inside temperature had dropped four degrees! Checked everywhere for leaks, nothing.
People, for some reason, are 'scared' of these things. Well, the chance of water flooding into your van is not a merry thought. They are really easy to service. If anyone has one, I would be more then willing to talk them through a strip down and clean. Parts can be sourced from Cak-Tanks. I can only think that ours had been disconnected because of the blocked return pipe. oh: Dutch PDF doc and schematic on link below.
Dave.
http://www.freiko.nl/PDF/72836-nl.pdf