caravan water systems.

[graz1958]

Hi everyone,
I'm in need of some advice on my caravan water system.
We have an Avondale Dart 515/4 Millenium. We took it away for our first outing of the year last weekend. We'd drained it over the winter, so this was the first time we'd pumped water through since last September.
We did the usual thing of filling the external water barrel, put in the pump and started, one by one, getting a good flow from the cold taps. All seemed normal until we tried to do the same with the hot taps, absolutely nothing. Never experienced this problem before. I Checked the drain plug and fast drain on the water heater, they were fine. Tried again, still nothing. So I removed the drain plug, a some water came out, but I did find a small o ring down in between the prongs of the drain plug, not the larger one on the outside, don't have a clue where it came from, or if it's the cause of the problem.
Any ideas?
Thanks.

 

[ProfJohnL]

Hello Graz

The small O ring is almost certainly related to your problem. I assume you are talking about a Carver Cascade II heater. On the cold water inlet to the heater there is a non return valve. This a white plastic fitting where the cold water Usually blue pipe connects to the heater.

With any luck (but its not guaranteed) you may be able to unscrew the plastic fitting inside the caravan. Again with any luck you may be able to dismantle it, refit the o ring and it may work again. Failing that you can still find the non return valve on sale at some caravan dealers, or on line.

What has almost certainly happened is even though you thought you had drained the system fully before winter, there may have been a small amount of water left in the pipe. This will have frozen and as it expands inside the fitting it can push the o ring out of position and jam the valves operation. Best advice is let the system drain then blow air (not exceeding 1Bar pressure) down the pipes to get rid of thewater in these low down places.

 

[graz1958]

Thanks for the advice, having looked at exploded images of the, as you assumed correctly, Carver Cascade heater, I was beginning to wonder if it had anything to do with non return valve. I will try what you have suggested when I get the opportunity, and, fingers crossed, things will go well.
Thanks again.

 

[graz1958]

Hello again ProfJohnL,
I did as you suggested, i.e, removed the cold water inlet/non return valve from my Cascade water heater. From your description, I guessed that it may not be straight forward, and that is exactly as it turned out. Being a plastic/nylon fitting the old one eventually sheared off, so I ended up having to remove the heater, and then, very carefully, I eventually managed to remove the rest fitting.
I have now replaced the cold water/inlet valve, put the water heater back into position, and today we filled it with water to test it. And surprise, surprise, it worked fine.
So thanks very much for your advice. I can now go on holiday.
Graham.