This morning the water tank on our carver water heater split in half due to corrosion. Having looked into replacing it I have discovered (as most of you already know!!) that it is no longer manufactured. I am not certain, but it looks like the Henry alternative is unavailable anywhere.
What is a recommended alternative. I have seen the electric only water heaters at half the cost of the gas/electric and wondered if they are a decent alternative. Since getting our caravan at the end of last year we have only been out in her a handful of times and always stay where there is electric hook up, so never needed the gas side of the water heater.
We have a superb condition 1997 Bailey Pageant Auvergne, which aside from this issue has been brilliant.
I am a reasonably skilled DIYer and am happy with doing the replacement myself.
I have had a look on Ebay and there are several Carver Cascade MK II hot water tanks available but they are not cheap. You cannot buy an electric operated version only as Carver initially made a gas operated one then added the electric feature on the MK II version called the GE. You are quite right in saying that they are not manufactured anymore and a company called 'Henry' did take over took over but there are numerous caravan breakers that stock them plus look at online websites such as Preloved.
I'm surprised that the tank has split in half as the casing is manufactured from stainless steel which doesn't rust and that's one reason for them being expensive as well. If there is evidence of a water leak then it could be a defective 'O' ring that seals the complete circumference of the tank against the flange which is bolted together by 4 x tie rods. If the large 'O' ring has perished then that is available as a spare replacement part which is also available online. To identify the parts list, do a Google search for 'Carver Cascade MK II exploded view' and you will be able to identify every single component that makes up the complete Carver Cascade water tank.
I have not had a chance to have a look at it myself yet, I got a call from my wife while I was at work, so I will have a proper look at lunch time. Hopefully it is just an o-ring, as that will be a damn sight cheaper than a new heater!
If I do end up replacing the whole unit I was referring to the something like the Propex water heater (https://www.thecaravanshop.co.uk/water-heaters/propex-water-heater-10litre/prod_769.html) as a possible replacement rather than an all electric carver.
I have reservations about buying second hand, due to the cost/age of them I am concerned about having problems sooner rather than later. Not sure if I am being over cautious.
Having looked at the exploded drawings I think that the o-ring around the circumference could have gone, which would explain why it looks like the unit has split. Either way I will have a better look later and get back to you.
As an update I have just managed to have a look, and combined with your advice before, I am fortunate that it is just the tie bar which has corroded and snapped. A quick google has found me one and courtesy of these forums, lots of advice and pictures to replace it.
Yes, if one of the tie rods have broken which secures the tank to the outer flue then the sealing 'O' ring will fail causing a loss of pressure which is creating the leak. When you strip the tank down make sure that all the other tie rods are in good condition because due to the fact one as one has failed then it may lead to another in the short term which is the task of doing the whole job again.
As a piece of advice, all the tie rods need to be tightened equally as the big 'O' ring sits in a small funnel like trumpet that seals against the flue so you may have to loosen each one of the tie rods and then tighten them up equally to maintain a perfect seal. The non return valve is a part that can often cause problems on this model and is much easier to replace when the tank is removed. For the sake of about 8 quid it may well be worth replacing it especially if you have had problems with back pressure at the water housing or problems with the water system pressurising.
Quote: Originally posted by tango55 on 31/8/2017
Yes, if one of the tie rods have broken which secures the tank to the outer flue then the sealing 'O' ring will fail causing a loss of pressure which is creating the leak. When you strip the tank down make sure that all the other tie rods are in good condition because due to the fact one as one has failed then it may lead to another in the short term which is the task of doing the whole job again.
As a piece of advice, all the tie rods need to be tightened equally as the big 'O' ring sits in a small funnel like trumpet that seals against the flue so you may have to loosen each one of the tie rods and then tighten them up equally to maintain a perfect seal. The non return valve is a part that can often cause problems on this model and is much easier to replace when the tank is removed. For the sake of about 8 quid it may well be worth replacing it especially if you have had problems with back pressure at the water housing or problems with the water system pressurising.
Hi Tango, to help me get it straight in my head, I can only see one tie rod - the long rod which sits in the centre of the tank and is threaded into the gas heater then has a nut on the electric heater end to hold it all together. That has sheared off in the gas heater end. It is item 13 in this picture http://www.swift-owners-club.com/support/oem-handbooks/carver/cascade-mk2.html
I am not sure where the other tie rods are located, would you be able to point me in the right direction, because as you say, for the sake of a few quid it seems silly not to replace them all at the same time.
My apologies for stating that there are 4 tie rods. I was thinking of a hydraulic or pneumatic cylinder which hold extreme pressure so has to have 4 tie rods on each corner. It's been about 8 years ago since I stripped a Carver Cascade water tank apart so it's been a while and can sometimes forget things. So, yes, you are right, there is only one tie rod in the centre but glad you bought this to my attention as the last thing I want to do is provide innaccurate information. At least one good thing is that you only have to replace the one single tie rod.
Sorry for for any misleading information.
Quote: Originally posted by magicgrotto on 01/9/2017
There is only one tie rod ! the problem may be getting the rotted end out ! But if your careful you may be lucky !
Fingers crossed! Looks like it's goint to be a couple of weeks until I get the chance to sort it, but I will update when I do.
Quote: Originally posted by tango55 on 01/9/2017
My apologies for stating that there are 4 tie rods. I was thinking of a hydraulic or pneumatic cylinder which hold extreme pressure so has to have 4 tie rods on each corner. It's been about 8 years ago since I stripped a Carver Cascade water tank apart so it's been a while and can sometimes forget things. So, yes, you are right, there is only one tie rod in the centre but glad you bought this to my attention as the last thing I want to do is provide innaccurate information. At least one good thing is that you only have to replace the one single tie rod.
Sorry for for any misleading information.
That's not a problem, you pointed me in the right direction to start with, I appreciated the help.
Many thanks for the kind words, it is much appreciated.
When you have repaired the tank, on installation make sure you clean the external surface area around where the flue sits on the outside with some white spirit to remove any of the old gunge (previous seal). Then wipe over and clean with some polish to remove any remaining surface film to clean it 100% so the new waterproof sealant bonds effectively to avoid any leak from rain water. When you tigten up the fixing screws and the flue compresses against the caravan side, the new sealant will squeeze out around the perimeter which on completion just use some white spirit and an old cloth to remove any unsightly gunge. It's a bit of a messy job but visually you end up with a professional cosmetic finish.
Will do. I might be able to get away without having to remove the flue, it will depoend on how well I can get the drill in to remove the threaded bit which snapped off inside.
A little update. I have now spent the last couple of days trying to remove the sheared off portion of the old tie rod. Using a screw extractor prooved useless in the end, the old bit was corroded in so tight that I nearly snapped the screw extractor. In the end I drilled out what was left and managed to remove the remainder with a tap, cleaning out the thread.
This is the point where I think it went pear shaped.....On threading in the new tie rod I dound it would not go all the way in, so I continued to drill/tap until I could do it up tight. I then went to reattach the tank only to find the ramining screw thread was too short to do the nut up with. After some whimming out of the tie rod I managed to assemble everything with no leaks coming from inside.
Water heats lovely using the electric element, happy days...or so I thought!
I could hear dripping and had a look outside the caravan only to find water merrily dripping away on the lower edge of the water heater. My question is, have I drilled though something important, or is it likely to be something less drastic. If I have drilled through something any suggestions on how I can fix it please!
Further update. Turns out that I had drilled right through the heat exchanger. I have been keeping an eye on ebay for a replacement and was lucky enough to stumble across a new old stock item. I have ordered and received it, I am over the moon to report that it is exactly as describe, a brand new never been use heat exchanger! I will be stripping and rebuilding the old heater once I get an opportunity!