Advice on changing hot water cylinder please

jack of all

Hi

I'm hoping I can get some advice on changing my hot water cylinder. I suspect there is a leak in the coil as the F & E tank is filling up (although very, very slowly, it could take a week or more to overflow). I am an enthusiastic DIYer and very happy to take on this job myself so all advice is welcome. The cylinder in question is coming up on 9 years old and I put it into replace the original cylinder which was fitted when the house was built in 2000. I thought I'd get longer out of this cylinder but there is a lot more hot water being used in the house with growing teenagers I suppose. Other than this issue I've had no problems with hot water or heating in the house, the system works well.

The cylinder is a grade 2, single coil rapid recovery, factory insulated 42x 18. I think I paid less than €300 for it 9 years ago. The same cylinder today is being quoted at anywhere from €670 to €850 which seems like madness to me and a lot to pay out in January. I may need to get the old oil fired heating system replaced in the future so I am thinking that maybe I should just get a grade 3 cylinder for now as no doubt the whole system will need to be looked at anyway.

Now for my dilemma- I can get a Joule single coil cylinder 36x 18 for only €200. Including a few fittings, inhibitor and new immersion heater I'll have change from €300. Only downside I can see is that the cylinder will have a smaller capacity (but still plenty for 5 people I'm thinking) and some modification of the pipework to the cylinder connections is inevitable. Would a 27" dual immersion be appropriate for this cylinder? Am I missing anything? Thanks in advance

cnocbui

I recently replaced my HW cylinder. I have very hard water and replaced the copper one with a stainless steel one in the hope it might last longer.

jack of all

Thanks for your reply. I live in a very hard water area also, however I do have a water softener fitted. I'm sure a stainless tank will cost considerably more, I'm just not sure it's worth spending too much on a replacement if I'm going to be upgrading the whole system down the road.

cnocbui

My 30x18 ss cylinder cost €160 in 2018 and included an immersion element.

John.G

https://www.boards.ie/discussion/2058226218/advice-on-changing-hot-water-cylinder-please

Presume the CWST level higher than the F&E level to allow filling/overflow of the F&E tank?. and obviously F&E tank ballcock not passing?

If you do change to the 36" cylinder then you are losing ~ 20 litres of water which = 33 litres when used at 40C from 60C, a fair bit with growing teenagers?.

anheneti

Priced one in Heatmerchants

42x18 G2 indirect insulated is €395

Crocodile Booze

It's a tough enough job.

1) Be carefully prepared on how you're going to seal the threads on the fittings.

2) Also, it can be tricky to get everything lined up.

3) Don't overtighten or you could crimp or buckle the connections or coil.

Advanced DIY in my opinion. Good luck.

jack of all

Thanks for all the comments, waiting on calls back from two more suppliers, incl. Heatmerchants. Will go with same size cylinder if I can get it at that price.

Living Off The Splash

We have been trying to get a plumber to replace our water cylinder since October. We live in Blackrock, Dublin. Four plumbers have been contacted now. One called to our home and said that he would be in touch......never heard from him again. Nor the others.

Is it a difficult job?

Can someone recommend a reliable plumber in our area, who will call, advise, purchase and install a new water cylinder?

Thanks

Living Off The Splash

10-10-20

https://www.boards.ie/discussion/comment/118431691#Comment_118431691

I live in about 2km from you. I had a small leak in my heating system in November in a somewhat difficult to reach spot and also needed an expansion vessel installed as well as the ancillaries for it. I called three plumbers, all reputable names, only one responded. Two lads came to the house, had a look, said they'd issue the quote - never heard any more.

Ended up doing the whole lot myself.

All I can advise is that you'll need to be persistent. It's not like it's uneconomical for them to do a cylinder replacement, they get the hours paid for and they get to trade in the copper for the prix-du-jour.

cruizer101

https://www.boards.ie/discussion/comment/118427695#Comment_118427695

Thats just the normal one not the rapid I presume. The rapid seems to add a fair bit, I'm not familiar with it so don't know how much extra its worth. Looking myself at replacing cylinder and was considering the rapid.

For a 42x18 single coil from plumbingproducts.ie the prices are

300 Grade 3

382 Grade 3 Rapid

428 Grade 2

632 Grade 2 Rapid

So big difference between them

jack of all

I've ordered a 42x 18 G2 (standard coil- not rapid recovery) from Heatmerchants for €399 incl. VAT, hope to have it next week. Two builder's merchants quoted me €850 for a rapid recovery cylinder, it's not worth the extra. The rapid recovery coil can have either fins on the coil (all the better to fur up with lime!) or additional coils of (plain, unfinned) pipe, no way either can justify the money being asked by the builder's merchants. Just goes to show you have to shop around or you can be robbed!

anheneti

https://www.boards.ie/discussion/comment/118431885#Comment_118431885

Yeah my mistake I never copped it was rapid recovery

John.G

Rapid recovery coils also base their rapid? recovery times as well on a 80C flow temperature and very high circ flow rates through the coil. Some boilers have DHW priority that automatically increase the boiler temp to this 80C and return it to its original set point when cyl stat satisfied. A standard coil if the boiler temp is set to 70C will still give reasonable recovery times especially up to a DHW temp of 50C or so which is fine for showering etc, it can then get it up to 60C at its leisure when no demand later on.

cnocbui

I shuddder to think what would happen with 80°C temperatures with my well water.