Replace HW Tank with....?

[Arborbridge]

My hot water tank in the cupboard is over 30 years old now I guess ad, going by various websites, I should be thinking about a replacement.

The tank is electrically heated on Economy 7 and has 120 litres capacity. It takes a fair amount of space up in the cupboard.

The thing ism since we got rid of the bath a couple of years ago, we don't need 120 litres of water on tap. We have 2 hot taps in the house and it was one of those taps that boil water on demand that got me thinking if there was a neater solution. I know I'll lose the water heated up on Economy 7, but surely 10-15 litres per day heated on demand would be cheaper than 120 litres heated overnight?

Also, I don't really need the water to come out of the tap boiling. Just enough to wash dishes, hands etc. The current thermostat is set around 65 degrees from memory and that's plenty. And rather than have the heater attached to the taps (as it is with the likes of Quooker etc) I could have it in the cupboard where the tank used to be.

Any thoughts?

If you propose not having a hot water tank, you may mourn the loss of an airing cupboard. I'm in that position in the houses I'm looking to buy, and I must say not having an airing cupboard is a distinct downside. Modern systems may be more "efficient" (though I doubt it) but that isn't the same as "better".

[staffordian]

Reading your post brought to mind an ad I saw recently. No idea if it's any good or not, but here it is, for what it's worth...

https://www.fischerfutureheat.com/elect ... KAQAvD_BwE

[swill453]

I think this is the kind of thing I'm looking for....

https://www.amazon.co.uk/Thermomate-Ins ... 166&sr=8-3

It says you install it near the point of use and it copes with one or two outlets. So they'd probably say you need one per bathroom and kitchen.

Scott.

[todthedog]

How about an instant hot water shower for example

https://www.amazon.co.uk/Triton-Seville ... 102&sr=8-8

and a small instant demand hot water tap, the boiling taps on tv are a grand a pop

https://www.screwfix.com/p/ariston-aure ... -5kw/305fj

regain a cupboard.

[richlist]

Get solar panels......then you can have virtually free hot water, won't need to remove the tank and no builders mess.

[modellingman]

I have the shower (fitted a couple of years ago)

There's not much space under the cupboards (particularly the bathroom cupboard) and getting an electrical feed to them might be awkward (again, the bathroom tap in particular)

I think my solution is a beefed up version of one I found in Amazon a few posts ago that can go in the same cupboard as the current water tank (Water connections, electrical power available etc)

The electrical power supply will, in all likelihood, need to be replaced. What is adequate for an immersion heater will come nowhere near being adequate for the sort of instantaneous heater you are considering. The supply to your cupboard will either be 2.5mm sq cable or possibly 4mm sq. For a 12kw heater you are possibly looking at 10mm sq, or even 16 mm sq, cable. Recabling the circuit with a suitably meaty cable is potentially going to be very disruptive, depending on where the cables run/can be run.

Unless you are going to be running hot water into both sinks simultaneously then I think you are over-egging the pudding. There are lower power instantaneous heaters available which won't require quite such a heavy duty supply.

Alternatively, a much smaller tanked system might be adequate. This one for example: http://waterheaterstore.co.uk/Water-hea ... oWay-Lemet.

[modellingman]

Alternatively, a much smaller tanked system might be adequate. This one for example: http://waterheaterstore.co.uk/Water-hea ... oWay-Lemet.

Thanks. Much food for thought.

Would you know if the smaller tanked system at the of your post would run off the existing economy 7 overnight electricity? I cant see why not.....but you never know.

I can't see why not, but there may be a few other things to consider.

Generally, E7 tariffs provide that all the consumption in the overnight period is charged at the lower rate. However, there are metering arrangements where only certain circuits (usually heating and hot water) benefit from the lower rate. Worse, in some of these arrangements these lower rate circuits can only be energised during the overnight period. If you are unfortunate enough to have such arrangements then you'd have to check that the supply to your intended location was one of these lower rate circuits. Chances are it will be if you are swapping over from a large storage tank to a small one, particularly if the property you are in was built as all electric with storage heaters as the main source of heating.

The existing supply should cope with the load without issue: immersion heaters are typically rated at 3KW and the product I identified is 2KW, so less current required through the circuit.

A note of caution, however. These types of tanks are used a lot in warmer climates. I'm not sure how insulation levels compare to the typical storage cylinders used in the UK, so you may want to check out heat loss and the impact that might have on the temperature of water available to you say late afternoon or the evening if you are not able (or don't want) to top up the stored water temperature outside the off-peak period.

If you have a poke around the Water Heater Store website you will find similar heaters ranging from 5 and 10l up several hundred litres. We had a similar 35 l tank in a house in the Canaries but found it too small and replaced it with a 50l unit which only lasted 4 years before it failed. This may have been due to over-pressure (there's discussion of this on website) or, possibly, the quality of the water supply. On the plus side though they are a doddle to swap out.

[modellingman]

A plumber has suggested an electric powerflow water heater, 30 litre. Similar to this type of thing I would guess...:

https://www.tlc-direct.co.uk/Products/H ... 6oEALw_wcB

Located in the same place as the current 120l tank.

My thinking is that this might be too complex for my needs and it might be worth fitting another, albeit amaller 20 or 50 litre economy 7 tank.

As far as I can see these are just expensive versions of the smaller electric tanks that we have previously been discussing. The difficulty you face in the UK with all these tanks is building regulations which require, amongst other things, installation by a competent person, pressure relief valving and inclusion of a pressure expansion tank in the installation.

[jaizan]

Electric showers seem to have much less stable temperature than mixer showers. Also, they need replacing more frequently.

I quite like my hot water tank. It's heated from my gas boiler and if that failed, there is an immersion heater back up. If a combi boiler fails, there is no back up for hot water.

[AJC5001]

My hot water tank in the cupboard is over 30 years old now I guess ad, going by various websites, I should be thinking about a replacement.

and

yes, but the point is that the tank is coming to the end of it's life and needs replacing anyway....

What websites are you looking at, and what makes you think it's about to fail?

My hot water cylinder is at least 50 years old and I can't think of any reason why it should fail - it's just a lump of copper with a few pipes attached. I suppose the immersion heater could fail, but that can be replaced fairly easily. Perhaps it might suffer from furring up if in a hard water area.

If you know what you would do if it were to fail, why not just leave it alone until it does
If it ain't broke, don't fix it.

Adrian

[AJC5001]

What websites are you looking at,

Type into Google 'lifespan of a copper water tank' and you see various estimates ranging from 8-12 years to 30 years or so:

A hot water cylinder generally last for if fitted to the highest standard about 30-plus years.

https://www.emergencyplumber.uk.com/plu ... -problems/

I might have a bit more faith in that site if it didn't contain quite so many spelling/grammar errors.

"Carbone Monoxide" ?

"In 10-year plus this cylinder has a good chance of being discontinue" ?

"It is also believed that there may not be another hot water cylinder that will be sold to so many people where there will be more of a choose of cylinder." ?

"As hot water cylinders get more clever in design the harder and more complexed they because to fix when it comes down to hot water cylinder problems." ?

"The pipe that is all by it’s own and comes gravity fed from the hot water storage tank above, is known as the hot water cylinder feed or cold water supply to the cylinder." ?

"A rust spot can be cured depending on how bad it is" ? Rust? On copper?

Adrian

[Howard]

My hot water tank in the cupboard is over 30 years old now I guess ad, going by various websites, I should be thinking about a replacement.

The tank is electrically heated on Economy 7 and has 120 litres capacity. It takes a fair amount of space up in the cupboard.

The thing ism since we got rid of the bath a couple of years ago, we don't need 120 litres of water on tap. We have 2 hot taps in the house and it was one of those taps that boil water on demand that got me thinking if there was a neater solution. I know I'll lose the water heated up on Economy 7, but surely 10-15 litres per day heated on demand would be cheaper than 120 litres heated overnight?

Also, I don't really need the water to come out of the tap boiling. Just enough to wash dishes, hands etc. The current thermostat is set around 65 degrees from memory and that's plenty. And rather than have the heater attached to the taps (as it is with the likes of Quooker etc) I could have it in the cupboard where the tank used to be.

Any thoughts?

Snorvey, thank you for starting this thread. It set me thinking.

Our downstairs loo is a long way (as the water flows) from our thermal store in the airing cupboard. This means that even in summer, it takes an age for the hot tap to deliver warm water to the basin. In winter, it takes around a minute for the water to start warming up. Washing hands properly has been a waste of time and a waste of water!

So I decided to invest in a modestly priced (£50) inline electric water heater. Bought from Amazon. The link to the actual heater I purchased is shown below, it is not in stock at the moment but virtually identical models are available.

It was a fairly easy DIY installation. The basin is on a vanity unit with plenty of concealed space below and luckily there was a 13 amp supply the other side of the wall, so an easy drill through, and a socket fitted under the basin. I was able to connect the fairly small unit to the plumbing using an extra flexible pipe and a connector to the hot tap.

The improvement is amazing. Now, within a few seconds the water runs warm and with a reasonable flow rate gets comfortably hot very quickly. So ideal for a hand wash.

The installation was completed around four weeks ago and, prompted by writing this post, I realised that I haven’t tried running the tap for several minutes to see how hot it gets when fed by the hot water which finally gets through from the tank upstairs. Having just done this, the unit (which has a digital temperature display) appears to switch off the heating element when the temperature reaches 57 degrees - a bit hot (but not dangerously so) for a comfortable wash.

I hope this experience may be helpful for anyone considering a similar installation. In my view, the heater would be suitable for the supply to a sink used for modest amount of washing up as well as hand washing. To get the highest temperature, one has to reduce the flow a little. But it has improved my quality of life and allows me to enjoy proper virus-killing hand hygene!

https://www.amazon.co.uk/gp/product/B07 ... UTF8&psc=1

regards

Howard