On Wed, 31 Mar 2021 16:56:09 +0100, Martin Brown
wrote:

On 31/03/2021 16:17, Mike Halmarack wrote:
I'm seeking some advice on choice of electric, undersink boiler.
I only have a need for hot water, Maybe 4 washing up bowls a day, 8
washhand basins full per day ( unless the water from the boiler is
drinkable and then 8 kettles full per day too).
Can anyone recommend a small undersink boiler that will be suitable
for this?

The ones in our VH are 25L capacity 3kW so best off hardwired in. They
are fine so long as you don't turn the tap on and leave it running until
it gets hot. There is only 25L of hot water available and when it is
gone it takes a while to heat back up again.

Things to watch are you will need an overflow/vent outlet and you might
need a pressure regulator to bring your mains water pressure down to
something that the boiler will cope with. They seem to last 5-7 years.

Otherwise you will find it leaks/drips overnight when the water pressure
is at its highest. Apart from that they are relatively trouble free.

Also, would the smaller type of electric boilers have a plug-in rather
than a hard wired option?

Decent ones at 3kW need a bit too much power for that. Proper flash
boilers that do hot water on demand need even more power to work.

Really informative, thanks Martin. Considering all that, I think I
would prefer to go for the flash/instantaneous option, even though the
power supply would need to be hard wired.
--

Mike