New boiler / heating system options

Bar-Ad

Needs some advise.
Have just moved in to a bungalow and am going to extend into the loft. The existing boiler is very old and needs to be replaced.
We had different builders suggest different solutions:
1. Install a new boiler with an unvented hot water cylinder (pressurized system)
2. Install a combi boiler
3. Install two boilers - one for the ground floor and one for the loft rooms.

I am very confused! :eek:
What is the best solution that will keep maintenance and usage costs low and also supply the required amount of hot water to the house (2 bathrooms/showers, kitchen and one guest toilet)?

Thanks

Cardew

Without knowing full details of the property - size etc - nobody can really offer accurate advice.

A combi will not cope with 2 showers on at the same time - in winter the temperature/flow is barely enough for one shower.

Unless the bungalow is huge, two boilers would appear to be an unnecessary complication and expense - 2 boilers to service is a considerable additional expense.

A personal opinion would be to go for the unvented hot water system with a single boiler.

Bar-Ad

Thanks.
The property size roughly:
- Ground floor ~120 square meters, 2 bedrooms, toilet/shower, kitchen and open space living room and dining room
- First floor ~60 square meters, 3 bedrooms, house bathroom and an en-suit

Pincher

Two central heating boilers is silly,
unless the loft is a separate flat.

It's unlikely that a combi can supply three bath/shower rooms simultaneously.

One GCH boiler plus a 180 litre (sized for two bathrooms) hot water cylinder and one instant hot water gas heater is definitely worth considering.

The hot water run to the most remote shower/bathroom could mean that you waste a lot of water every time you turn on the tap. Ideally you want to cluster all the hot water usage points close together, and supply all of them from the cylinder, but there is always an outlyer or two.

I would supply the kitchen and one closest bathroom with the instant hot water heater, and the other two bathrooms from the cylinder, which should be located close to them. This gives you greater parallel capacity in case all three bathrooms are in use simultaneously.

Ideally, you want to locate gas appliances in an outside lean-to or boiler room, but there are now external versions you just mount on the external wall in the open air. Advantages:

No flue to drill through the wall.
Run the gas pipe outside, easy, and no risk of gas leak inside.
Condensate drip pipe run to the nearest drain, easy.

ziggyman99

I agree with Cardew. Unvented is a good way to go. Obviously you will be struggling to get a gravity system to work in a bungalow if your using the loft space so I would advise you to go for a sealed system boiler.
Why is a bungalow called a bungalow?

Because they started to build a house but someone decided to bung a low roof on it - i'll get me coat

Bar-Ad

Thanks for the answers.

One more question if you don't mind: - Can the hot water cylinder go in the garage? I mean, will it increase usage if located in a place with no heating?

Cardew

Bar-Ad wrote: »

Thanks for the answers.

One more question if you don't mind: - Can the hot water cylinder go in the garage? I mean, will it increase usage if located in a place with no heating?

Two problems with the garage.

Firstly any HW tank no matter how well lagged will lose heat - around 2kWh a day. That isn't such a problem most of the time as that lost heat goes to heat the fabric of the house - and why many tanks are situated in an airing cupboard.

However any heat loss in a garage will keep your garden tools or car a bit warmer.


Secondly - as explained above - it is advantageous to keep the pipes from the HW tank to the bathrooms as short as possible. You will waste a lot of hot water every time you run HW in the bathrooms if the pipes are very long.