Hot water tank question (including photos) and DIY disaster!

bryanb

A good friend of mine did exactly the same thing, his tank was above his neighbour's kitchen (flying freehold) . After the water had ruined next door's kitchen, he diverted it down his staircase and ruined his own electric undefloor heating. Moral - there is always someone worse off than yourself!

EliteHeat

The reason that the drain-off didn't work was almost certainly because the washer was sticking to the valve seat.

You would have been able to poke the hose down the header inlet and syphoned the contents out.

But, it's a bit late for this now! Nice photos though

tomstickland

Yes, I've read up on it now and syphoning it out is a common method.
Obviously I didn't intend to allow the water to deluge out of the bottom heater hole, but I was caught out by how short the thread was on the heater element.

I'm in a bit of quandary regarding cleaning this tank out versus getting a new one.

Could I use descaling solution?

EliteHeat

tomstickland wrote: »

Yes, I've read up on it now and syphoning it out is a common method.
Obviously I didn't intend to allow the water to deluge out of the bottom heater hole, but I was caught out by how short the thread was on the heater element.

I'm in a bit of quandary regarding cleaning this tank out versus getting a new one.

Could I use descaling solution?

What was the reason for draining down in the first place?

bookduck

tomstickland wrote: »

Could I use descaling solution?

Electronic descalers do for most people work over, but time (months, not years) which depends on the thickness of the scale. Just wrap the wire around the cold water inlet and there is no reason even to remove the tank?

tomstickland

EliteHeat wrote: »

What was the reason for draining down in the first place?

Replacement of immersion heater element due to failure to heat water.

tomstickland

bookduck wrote: »

Electronic descalers do for most people work over, but time (months, not years) which depends on the thickness of the scale. Just wrap the wire around the cold water inlet and there is no reason even to remove the tank?

I meant in terms of pouring some fluid into the tank when it's removed from the flat so I could dissolve the crud inside it.

mute_posting

tomstickland wrote: »

I've been doing some reading up on my options.

The cheapest option for me is to take the existing tank outside, clean it out and then reinstall it with new heating elements.

The next option is to replace the tank like-for-like.

After that things become a bit more complicated. I've been told by a few people to consider unvented mains-pressure systems. These essentially have a sealed tank of hot water and a heat exchanger with mains pressure water fed into it.

The other option is heat-on-demand.
I've yet to do the maths but I think the last option is probably more expensive to run.

Economy 7 with enhanced insulation I expect to be the cheapest method.
Having said that, any heat loss from the tank is essentially night-storage heating.

If you are considdeing mains pressure hot water I'd suggest going down the vented route with something like a gledhill pulsacoil, the problem with unvented is they have to be notified (I think) to building control and have services done yearly (from memory)

I hade a similar decision when I bought my flat (mainly because with the original hot water tank close to the ceiling, there was only about 50-60 cm head at the kitchen sink and about a meter at the bath - and was very slow running)

The the unit I bough is called a "Pulsasoil A Class" - obviously you need reasonable mains pressure in the first place!

HTH

MP

beer_tins

tomstickland wrote: »

I meant in terms of pouring some fluid into the tank when it's removed from the flat so I could dissolve the crud inside it.

Trouble is, you'll have whatever the "fluid" is coming out of your hot water pipes and the crud possibly travelling around to clog up your taps etc.

If you were happy with it all until the immersion heater failed, I'd just clean it and re-install with a new immersion heater. How old is the cylinder BTW? It's quite a build up in there but it looks new-ish (relatively speaking).

tomstickland

I've phoned up a few places today.
The general opinion is that I should replace the cylinder.

The prices for a like-for-like are a lot more than I expected.
£524 inc VAT from Graham building supplies, £526+VAT from Plumb centre.

I spoke to Newark this morning and they can supply an equivalent tank for £300 + VAT. Their heatstore is £650.


In summary, the options are:
-vented tank: like-for-like replacement
-unvented tank: requires annual inspection and certificate etc, plus there's a problem with routing the pipes from the safety vavles
-heat store. Essentially take the vented tank and instead of putting cold in and hot out they run mains pressure water through a heat exchanger coil, so the water in the tank stays in there.
Newark Copper cylinders (http://www.newarkcoppercylinder.co.uk/cylinders/thermal_store/)
around £650

Gledhill pulsacoil
http://www.gasapplianceguide.co.uk/pulsacoil-aclass.pdf

Another heat store: http://www.inspiredheating.co.uk/acatalog/Albion_Mainsflow_Indirect_Cased_Contractor_Cylinders.html