Surecal Calorifier Leak

[Chewbacka]

Hi all, thanks very much for bearing with us. We've sealed the immersion element's thread with PTFE tape, left it for an hour or two as per advice above, and as yet there doesn't seem to be any leak. The water is heating up, so without wanting to curse it, so far so good.

 

While we don't have an expansion tank, the PRV connects to a hose which leads outside, and that let out a bit of water when we got things running again. Does this hose negate the need for an expansion tank, or would it be advisable anyway?

I would suggest that if you have a non return valve on the cold feed to the hot system then you must have an expansion vessel. The surecal warranty requires one, otherwise the life can be much reduced. If you don't have a non return valve and you do have an accumulator on the cold system you may be lucky, but the pressures are different (different job). I have both an accumulator and expansion tank.

 

Note that the PRV is an emergency release, it is not intended for daily operation.

[MtB]

I would suggest that if you have a non return valve on the cold feed to the hot system then you must have an expansion vessel. The surecal warranty requires one, otherwise the life can be much reduced. If you don't have a non return valve and you do have an accumulator on the cold system you may be lucky, but the pressures are different (different job). I have both an accumulator and expansion tank.

 

Note that the PRV is an emergency release, it is not intended for daily operation.

 

 

Being picky, the pressures will only be different when there is a non-return valve in the calorifier cold feed connection, in which case two vessels (one each sire of the NRV) are essential to avoid early failure of the calorifier.

 

If there is no NRV, then a single accumulator just downstream the pump will function perfectly as an expansion vessel too. There may be some minor contamination of the cold pipes with hot water during heating of the calorifier as a result, which is why the calorifier manufacturers usually fit the NRV.

 

MtB

[Zosima]

Thanks all once again, will sort an expansion tank out pronto.

[ditchcrawler]

 

Spent ages on my last boat trying to get the immersion heater boss to seal properly on a new calorifier. Fernox LS-X sealant was the final solution (and good for a number of other things as well). This was after failing with ordinary silicone sealant. I am never without a tube at home or on the boat now.

We always used Bosswhite in domestic cylinders when I was fitting them, could be bit of a bugger to get out a year later.

[Zosima]

Hi all, muggins again here.

 

We've got ourselves a 5L expansion tank, but it's come with no instructions and Surejust's website seems only to have very cursory fitting instructions (as far as I can see, anyway).

 

So, erm, where does it go? Is there even room for it?! The instructions I have found say it goes between the thermostatic mixer valve and the first outlet.

 

Pic (sorry for the quality)

 

The thermostat is the black thing you can hardly see at the bottom, and it's right next to the outlet pipe. There's nothing I can stick the expansion tank in between the two. Am I right in thinking I need to source a bit of pipe with the requisite inlet (and if you could enlighten me as to the actual term for such a 'bit of pipe'... I'd be grateful).

 

Thanks.

[bottle]

The expansion vessel can go anywhere between the tank outlet and the first tap.

 

After the white valve, if that goes to your taps.

[Zosima]

Thank you bottle.

 

I'm afraid I have another chapter in this opus of woe, however.

 

Two elements have failed in the last two weeks. They both have had exactly the same problem. Here's a picture of both.

 

As you can see, part of one of the connections has snapped off. The same connection on both (it's the one the blue wire goes into - not sure if these colours are universal, but maybe that'll help).

 

The right one is a bit rusted, we're fairly sure as a result of its submerging due to poor sealing (as detailed early on in the thread). So we thought that one was our fault, ordered a new one and expected it to be fine, once it was properly sealed. And exactly the same part has broken. We realised, on both occasions, when the hot water supply stopped, and we opened it up to check whether everything was still connected (btw the boiler light remained on despite the snapped part).

 

Frankly I'm now at the stage of asking for recommendations of local plumbers/electricians who are good and insured to work on boats, but I thought I'd ask to see if anything sprang to mind.

 

(The expansion tank was not and is still not installed by the way - but it CAN'T be just that, given that we had uninterrupted hot water for 6 months without one, can it?)

 

Thanks for any thoughts.

[bottle]

The one on the right is corrosion, (water ingress) the one on the left is mechanical (the pin is bent)

 

It may be possible to solder it back on or take the whole thing back as not fit for purpose.

 

It came off when you tried to push the connector on.

[ditchcrawler]

The one on the right is corrosion, (water ingress) the one on the left is mechanical (the pin is bent)

 

It may be possible to solder it back on or take the whole thing back as not fit for purpose.

 

It came off when you tried to push the connector on.

I don't think it would solder, probably spot weld.

[bottle]

You're probably right.

[MtB]

The terminations on heater elements are rather prone to coming off like this. When I get this occasionally, I connect the cable with the brass core cut from an ordinary 'chocolate block' type of cable connector. The conductor rod on the element fits into one nicely. Use the 15 Amp size.

 

MtB

[bottle]

Brilliant Mike, now why didn't I think of that.

 

Don't answer that.

[ditchcrawler]

The terminations on heater elements are rather prone to coming off like this. When I get this occasionally, I connect the cable with the brass core cut from an ordinary 'chocolate block' type of cable connector. The conductor rod on the element fits into one nicely. Use the 15 Amp size.

 

MtB

Which is what I have done in the pats but not on a brand new one. I would take it back to where I bought it.

[Zosima]

Thank you for the input all. Will see if we can get the newer the one replaced.

[NB Rosie Lee]

I know this an old topic but I have the same problem.   Do I need to unscrew the "boss" to put sealant down or just around the outside? Sorry if it's too late for this reply but I'm clutching at straws for an answer to leak

[Tacet]

To remake the immersion heater joint, it needs to be removed from its boss.  The boss remains joined to the cylinder 

 

It's unusual for this joint to start leaking if it has been dry for a good while.  If it looks to have started to leak only recently, I suggest a careful examination to make quite sure where the trouble lies before fiddling further.

[nicknorman]

32 minutes ago, Tacet said:

To remake the immersion heater joint, it needs to be removed from its boss.  The boss remains joined to the cylinder 

 

It's unusual for this joint to start leaking if it has been dry for a good while.  If it looks to have started to leak only recently, I suggest a careful examination to make quite sure where the trouble lies before fiddling further.

However that is exactly what happened to our boat after 10 years. I thought the calorifier had split, but I finally traced it to the immersion threads. I replaced the fibre washer, but it still leaked. I then applied PTFE tape to the threads. This fixed the problem.
However it’s worth bearing in mind that the seal is/should be the fibre washer. The PTFE tape helped primarily because it lubricated the threads and allowed me to tighten the immersion more - well, it went further round for the same force, crushing the fibre washer more. It felt quite different with the tape on the threads, a nice sliding of metal on metal gradually getting tighter, rather than jerky catching unlubricated metal on metal.

[Tracy D'arth]

Check that the PRV is not jammed closed, if it is the excess pressure will cause leaks and ultimately split the calorifier.