Changing hot water cylinder in house - how big a job?

RMCF

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I have an old cylinder lagged with one of those usual red padded jackets which doesn't keep my water hot for very long.

I want to change it over to one of the foam insulated ones, as I had one of these in a previous house and it kept the water hot for a long time.

Wondering how big a job it is to replace a hot water cylinder? What sort of time(hrs) can I expect a plumber to take at it, or what is likely to be a rough cost of doing it (aside from buying the tank itself).

Btw, the cylinder is downstairs, if that makes any difference.
 
My brother changed mine last year for me, it took him the bones of a full morning, the new tank cost me 250 or so, cant remember exact price, it is the normal size one, not the floor standing big type. The pipes didnt line up exactly with the fittings because of the extra thickness of the new tank insulation so there was a lot of fiddling around trying to get it to fit. If it had been a direct swap it would have been much quicker. (By the way he knew what he was doing so it wasn't slower than it should have been)

Originally when I moved into my house, short of money etc, I didn't buy a proper lagging jacket and I put an old duvet tucked in around the tank and covered it with a sheet and tied it all up neatly. Sounds awful I know but bear with me, anyway few years ago I looked at it one day and thought that's awful I should buy one of the proper jackets, off I went and bought it, threw out my old duvet and put on nice new red jacket. Low and behold, water was not staying as hot as it had done with the duvet, pretty much cold by morning in fact, put up with it for a while, then off with the fancy jacket and bought cheap duvet to put back on it. Now that I have my new insulated tank I dont need it but I dont really think the water remains any hotter than it did with the duvet.
 
A factory fitted lagging layer is going to outperform any sort of lagging jacket no question.

There are a few threads on the cost and issues involved in replacing a hot water cylinder/immersion but they seem to be a bit old so may not reflect current prices.
 
out of interest, what happens to your old tank? are plumbers offering to "take them away" do they charge for disposal? Copper scrap price is a premium lately, just wondering...
 
My brother changed mine last year took a morning to do it also, pipework needed to be adjusted slightly,Itook the old one to a local metal fabricator who cut the top and bottom off rolled it out and cut it into 4" strips which i used to fix pond liner to railway sleeper edging to finish the garden pond, this was my orignal idea but spent two years looking for wide copper edging strips to no avail, the base of it is now a birdbath and it the strips can be used to edge paths etc, if i was disposing of another i would ring an artist or sculptor and offer it to them
 
Job would take half a day or so.

Change the immersion while you are at it. Most professional plumbers will take all waste off site, even the stuff that is worthless. However cylinders are not worthless. Hang onto it and bring it to a local scrap place for about €30 - €40.

Expect to pay under €450 inc VAT for supply and fit, of cylinder, immersion, any fittings, pipe and inhibitor.
 
new cylinder

I had a new cylinder fitted this year and it cost €450. It took the plumber about a half day's work and some piping had to be adjusted. I brought my old cylinder and fittings to the scrap yard and got €55 for them. This seems to be the going rate. I suppose a lot of plumbers offer to "take away and dispose of" your old cylinder but I know for a fact that this is a nice little earner for the plumber as one lives next door to me and I'VE seen him heading off to the scrap yard with numerous cylinders and bags of scrap copper piping! So be aware of this when you have a new cylinder fitted.
 
On a side note, at present with a jacket you can feel the tank and see how much water you have available, be it for showers, having a bath etc.

If you replace it with one of the foam insulated ones, is there any way of knowing how much hot water you have in it? Was thinking that if you can't tell and say, for example, you want to go for a bath, you may end up putting on the immersion heater to make sure you have enough, but this might be unnecessary.
 
I think you can have a thermostat that gives a reading to whereever you want. I know I'm not explaining myself properly, but I was concerned about this in the house we are currently renovating and the electrician has said it's no problem to have a thermostat wired up with a box giving the reading in the kitchen and the bathroom.

This hasn't actually been done yet so I can't say with certainty that it works.
 
Depends on the size and quality of the tank. We had a small cylinder of the type the OP mentions and it was constantly running out of hot water when under pressure. Bit the bullet and replaced with a large cylinder well insulated but not so cheap at about 500. Hooked into heating system which has the water hot in 30 mins and we have it all day with low loss. Cost was a sting at about 1K but no more emmersion costs and no more poor results.
 
On a side note, at present with a jacket you can feel the tank and see how much water you have available, be it for showers, having a bath etc.

If you replace it with one of the foam insulated ones, is there any way of knowing how much hot water you have in it? Was thinking that if you can't tell and say, for example, you want to go for a bath, you may end up putting on the immersion heater to make sure you have enough, but this might be unnecessary.

This is a problem more common with stainless steel cylinders. The best way is fit, as Nige says, a thermostat gauge. With solar stainless steel cylinders I always fit an additional temperature sensor close to the top of the cylinder wired to the solar controller so that the level of the hw can be seen, top and bottom.

I would still prefer to have an insulated cylinder and not know the amount hw in it than having an uninsulated cylinder and know what I have. The time that I know I have hw will soon run out and I will then have none!
 
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