Leaking On Outside Of Carver Water Heater

[Richard_374300617]

Hi all,

Could you give me some advice regarding my Carver Cascade 2 GE water heater.

Was using it this weekend and noticed water leaking from the lower edge of the outside cowling, sometimes quite fast then sometimes slow and others not at all. The main drain bung was dry and water not appearing from there. There was no problems with the heating of the water, this worked fine. The inside of the van around the heater aperture was dry. Was on electric use not gas. Is this a seal gone? any help you can give would be a great help before the next trip out !! Many thanks, Richard.

 

[ProfJohnL]

Hello Richard,

I am guessing from your description that your water pump is controlled by micro switches in each of the taps, so the pump can only be powered when a tap is open. If this is the case, then it sounds as though one of the safety devices, the fusible plug in the heater may be venting some water. This will only happen when the pump runs and the water system becomes slightly pressurised.

The fusible plug is buried in the middle of the heat exchanger fin pack above the burner bar. It is designed to remain intact unless the heater over heats, when the plug will melt and relieve any pressure and steam into the burner. The plug is manufactured from a low melting point amalgam of metals, which is cast into the plug holder. Occasionally the casting may become loose over time in which case it may leak but only under the pressure from the pump.

If this is can be carried out without removing or breaking the gas seals, but as with all gas appliances the regulations require the work to be carried out by a competent person.

 

[rosies]

Hi Richard , also suspect this could be your QDV , Quick Drain Valve . this is found by removing your outer cowl and looking above your normal drain point in the top left hand corner . The QDV is a plastic bodied unit which after some time of temperature differences get hard and splits on the threads , if you just waddle this unit it will probably break off in your hand . If it does then it will leave the broken plastic male thread inside yuor water tank unit , PLEASE DONT try and remove the broken thread with an easyout , this will probably break your tank . Remove the broken section using a old junior hacksaw blade with one end cross pin removed , saw gently through the broken threaded plastic in at least 4+ places then remove each sawn section with a normal screwdriver . If you have been very careful then the metal tank threads should be in good order , but better to use an m16 tap . New QDV units are stocked at any good caravan accessory shop for about

 

[RonD]

Richard,

I agree with rosies...I had the same problem whilst away on holiday but managed to repair it exactly as suggested. It's a bit time consuming and tough on your fingers, I wrapped a cloth round the hacksaw blade. Try and be careful that no plastic bits go into the heater.

Ron D

 

[gary]

Life is made easier for the fingers if the hacksaw blade is bound with electrical tape to a screwdriver blade, leave about 40mm of the hacksaw sticking out over the end of the blade.

 

[gary]

And you don't use PTFE tape or any other sealant on the thread, there's a rubber 'O' ring that will seal the fitting as long as the fitting can be screwed fully home.

 

[Richard_374300617]

Many, many thanks everyone. Yes....it snapped off, and managed with all the advice, to hacksa with a junior blade and then a small screwdriver blade to clear the trhreads in the heater body. New one obtained via the mighty ebay for

 

[Jacko67]

Hi
I replaced my QDV as described in this post but some of the pieces have gone inside instead of coming out...Doh!!! , is it possible to remove these from inside the caravan by removing something on the inside of the heater or will they have gone into the heater and not be possible to remove???

Thanks

Ian

 

[ProfJohnL]

Hello Ian,

I cant recall if the plastic used for the QDV will float or sink. If you have any of the old fitting left just drop into some water and see if it floats or not. If it sinks, then I wouldn't be concerned as the will just sit in the bottom of the tank and do no harm, but if they float, then there is a danger they may be flushed out into the hot pipework and lodge in a tap or other fitting compromising their operation.

What I suggest you do is to remove the new QVD and then turn a cold tap the pump on which will fill the tank and eventually start to discharge through the QVD threaded boss. This is outside so it shouldn't cause a flood.

With any luck the bits of thread will be flushed out. Then turn off the pump and remove the drain bung. This may flush out any remaining bits. refit the QVD and the drain plug, refill the heater and you should be good to go.

 

[MacM]

Definitely use ptfe tape!
If you stick to the method this thing was assembled originally you’ll break every fitting on it trying to remove them.
Purists will say don’t use it B) but unless you want galvanic corrosion (cold welding) between your tie rod and your casting and all the plastic fittings snapping in half, if ever removing them then use it on everything you can. It will aid removal in the future and bomb-proof your seal as you’ll be sealing at the threads as well as relying on the face to face seal of the o-rings. Let’s face it - the crusty alloy face left on the casting for the o-ring to mate with, is usually in poor shape after 20-30 years of corrosion.
PTFE - Great Stuff !

 

[Parksy]

Thanks for your input MacM, but you replied to a thread that first began almost 11 years ago with the preceding comment added over 2 years ago.