Replacing hot water tank with combi boiler?

MobileSaver

One of the valves has gone on our hot water tank (in airing cupboard in ensuite) but the real problem is that the ensuite fixtures were added after the the tank had been installed so literally impossible to fix without ripping out the bath and/or sink unit to be able to get to the tank.

Now as it happens have been thinking of installing a bigger bath/shower unit anyway (by removing/moving the hot water tank.)

Would removing the tank and replacing normal (prob 20 yrs old) boiler with combi boiler be a sensible option for a 4 bed, 2 bathroom (1 bath, 2 showers) house?

It it makes a difference we're just outside the M25 in a very hard water area.

Thoughts welcome.

gas4you

In short no.

A combi will only adequately supply one hot outlet at a time.

Barneysmom

You could but instead of running the 2 showers from it, install 2 electric showers. That would be better probably.
That way if one breaks down or the boiler breaks down you still have access to hot water.

keith969

And to add to that, a hot water tank gives you some backup if your boiler breaks down - you can still get hot water from the immersion heater.

MobileSaver

Thanks everyone, clearly my original plan is dead in the water without replacing the existing showers. I'm not a big fan of electric showers but will look into them more.

If I wanted to move the tank rather than remove, how feasible would it be to have the hot water tank in the loft? It's a fairly big loft, all boarded with pipes already going directly up from the existing hot water tank to a cold water (expansion?) tank in the loft. Usable headroom is about six and a half feet.

Doable or am I stuck with having the tank in the ensuite?

1984ReturnsForReal_2

Barneysmom wrote: »

You could but instead of running the 2 showers from it, install 2 electric showers. That would be better probably.
That way if one breaks down or the boiler breaks down you still have access to hot water.

Might not be possible without expensive electrical work.

1 electrical & one of the boiler would be ok.

1984ReturnsForReal_2

MobileSaver wrote: »

, how feasible would it be to have the hot water tank in the loft?

The system you are on wouldn't work.....

& your house would just flood from the roof.

ziggyman99

1984ReturnsForReal wrote: »

The system you are on wouldn't work.....

& your house would just flood from the roof.

I'm not sure why it would do that. Yes it is possible to put a hot water cylinder in the loft. Your best bet would probably be a combi tank - the header tank is built into the cylinder. Very do-able.
Before delving too far down that road, consider whether you will fit a cylinder through your loft hatch.... their 450mm in diameter but 400mm are available.

MobileSaver

1984ReturnsForReal wrote: »

your house would just flood from the roof.

There's already two water tanks up there, why would adding a hot water cylinder flood the house?

ziggyman99 wrote: »

Your best bet would probably be a combi tank - the header tank is built into the cylinder. Very do-able. ... their 450mm in diameter but 400mm are available.

Yay some good news at last, thanks, hatch would easily allow 530mm diameter through it.

I'll look into combi tanks some more, never heard of them until today.

1984ReturnsForReal_2

MobileSaver wrote: »

There's already two water tanks up there, why would adding a hot water cylinder flood the house?

Because the hot water tank needs to be below its feed otherwise it wont vent & the water in the system will find its level (because its a gravity system) which basically means the hot water flowing back into the cold water cistern.

The ONLY way of doing it would be to raise your cold water feed cistern to a height 1.5 meters (for vent pipe) above the hot water cylinder which would be above most peoples roofs sitting externally above on the tiles.

mikey72

Vaillant ecotec 837 or 838 may be ok, depending on your water supply.