Water tank replacement - my options?

ComicGeek

Domestic hot water heat pump cylinders are a good option where there is sufficient mains water pressure, and it can be positioned by an external wall to get the air intake and discharge out simply. 

markin

Why is the white tap and pipe coming down from the ceiling, Could the be another cold tank in the loft and a tap on the pipe going up into the loft?

snic104

markin said:

Why is the white tap and pipe coming down from the ceiling, Could the be another cold tank in the loft and a tap on the pipe going up into the loft?

There's no tank in the loft, the pipe goes up into the the loft, along and down into the bathroom to feed the electric shower 

snic104

Jonboy_1984 said:

Have you considered the water pressures required?

Is it fed off the cold tank and if so where is the cold tank in relationship to it? If you haven’t used it and the cold is directly above it you may be shocked at how poor the hot water pressure is when you get it working. We are at 10-15 minutes to run a bath in our flat with the cold water tank immediately above the hot (ground floor flat in our case). 

If the cold water tank is already in the loft then you may not be able to relocate a convention hot water cylinder there as it needs to be physically lower than the cold tank.

If you are replacing then consider getting it updated to a direct unvented cylinder fed directly off the incoming water main, that removes the need for a cold water tank at all.

(Do be aware that fitted direct unvented cylinders is a licensed job and not DIY as it involves hot water at pressure)

There's no tank in the loft. The supply goes directly into the green tank, so does it sound like I already have a direct invented cylinder, like you suggest? (Sorry, I really don't know anything about water tanks!) 

snic104

Section62 said:

Jonboy_1984 said:

Is it fed off the cold tank and if so where is the cold tank in relationship to it?

Sitting on the top of it.

It's a combination cylinder, the cold water storage is at the top of the unit.

Quite common with flats and other buildings where there is no space/access for a cold water storage tank in the loft.

OP, the only thing I'd be concerned about is the dark mark below the bottom immersion heater.  This could be a sign of a leak, or could be the fitter was too liberal with their "Boss White".

Is the stuck valve the white one at the top left of the picture? If so, don't put WD40 on that one - it won't do anything beneficial, and may damage the plastic.  If not, where is it?

Thank you for your reply. I hadn't considered the black mark might be an issue! I'll certainly get it checked out.
The white valve feeds into the bathroom and supplies the electric shower. The valve that is stuck is a red wheel- type valve - I'll add more photos below. 

Section62

snic104 said:

...so does it sound like I already have a direct invented cylinder, like you suggest?

No, you have a "combination cylinder".

You can ignore the direct/indirect bit because you don't have a separate boiler.

Your current system is "vented" because the cold water storage at the top of the unit is open to the atmosphere and the hot water flows due to gravity.

An "unvented" system is pressurised by the mains water, there's no cold water storage, it isn't open to the atmosphere, and the water flows only by mains pressure.

There's no particular advantage in having an unvented system in your situation unless the mains water pressure and flow rates were high enough that you'd be able to switch to a thermostatic mixer shower without needing a pump.

Unless the hot water cylinder is leaking there's not much point in changing it.  The 'eco' option is to avoid throwing away something completely serviceable just to have something 'new'.

Section62

snic104 said:

The white valve feeds into the bathroom and supplies the electric shower. The valve that is stuck is a red wheel- type valve - I'll add more photos below. 

In which case, if the shower is working then the red wheel valve is almost certainly not the problem.  The float valve in cold water storage is more likely to be the issue.

snic104

Bendy_House said:

Good photos, Snic.

"Sitting on top of it.." - that made me laugh

As Plumb points out, that white valve 'could' be supplying the cold storage tank on top 'if' the cold mains is coming down from above. It 'isnt' supplying the CWS tank if the mains is coming up from below. So, first check, as he says, is to lift the lid and have a peep.

Can you do this? If you could take a photo of what's inside that top tank, that would help (you may need to Google what sort of lid it has, but I presume just a lift-off type?)

As also pointed out, if that is the CWS, then expect the water flow rate from taps to be pants, and a tank-fed shower to be out of the question without a pump.

Since you don't have gas, then some sort of STORED hot water is still probably your cheapest option, as you can charge it up on cheap rate leccy. The only alternatives are 'instant' heating systems, but these will be very low supply, and also full leccy cost (if used non-peak.

The usual advice you'd be given is to keep what you have as soon as it's made working again, which will likely be cheap and easy. However, you really want rid of it to make room to expand your kitchen?

Q - Do you really want to keep having baths?

 If 'yes', then the hot tank replacement will have to remain that size (but not necessarily with the top, cold, tank). If 'no - showers only are fine', then I think you could reduce that hot tank in half in size, and that should provide all the cleaning, dishwashing, and even showering hot water you'll need each day. A smaller tank to heat up, less weight to cater for in the loft, less heat loss as it's a smaller volume. (That's my theory at least - very happy to be corrected).

For showers you'd then have the choice of keeping an instant electric type - which are pretty awful, so go for the best you can - or swapping to a conventional thermostatic mixer fed from the new tank in the loft (which would give a better shower, and also be cheaper to run as it's heated by cheap leccy.) You'd need to ensure your new hot tank was large enough to provide all the hot water you'd need in one day.

Next step, I'd suggest, is to get some plumbers in to quote for shifting/replacing the tanks. They'll need good and safe access to the loft, and an idea of what YOU want from your new system.

May I ask - how many folk in your flat? And how long do you intend to stay there?

There's currently just me in the flat, and I'd be happy with shower-only, however, I may be looking at renting it out in the next year or so (but no definite plans as yet to do this) As it's just a 1-bed flat it would be better suited to a single person or a couple. 

The white valve supplies water to the electric shower - the bathroom is just to the left of the water tank cupboard, so the water supply goes up into the loft, along and down. 

Yes ideally I'd like to put the tank (or a replacement of some sort) in the loft so I could make the kitchen bigger. There's only space for two electrical items in the kitchen, I currently have an oven and a washing machine in there. The tiny fridge/freezer (which came with the flat) was in the cupboard directly under the water tank and plugged into a dodgy-looking socket whose cable runs along-side the water tank 😳 I have since moved it, but there's no room for it in the kitchen. (Ideally I'd like to have a water source in my porch on the ground floor, where I can plumb my washing machine into, but I fear that would require a whole new thread to discuss it! 🤣🤣) 

Photos attached - I hope they're useful! The brass tap above the floorboards  is where the water supply enters my flat. The red wheel- valve feeds into the tank and the white valve feeds the electric shower. 
Photos from the top of the tank looking down

snic104

ComicGeek said:

Domestic hot water heat pump cylinders are a good option where there is sufficient mains water pressure, and it can be positioned by an external wall to get the air intake and discharge out simply. 

That sounds a possibility if it could go in the loft - it would be on an external wall 

snic104

markin said:

Why is the white tap and pipe coming down from the ceiling, Could the be another cold tank in the loft and a tap on the pipe going up into the loft?

It feeds the electric shower