Buying a new house and have some concerns about the energy bills

andrewjf

The lack of water tank was confusing me, but this is in fact a 'system boiler'. Meaning the hot water cylinder is fed directly from mains water input, rather than gravity fed from a tank. So essentially, it's a similar system to what we currently have, minus the water tank. So really the main issue is probably the age of the boiler, and it really should be replaced as a priority. Whether the sellers would be open to knocking a bit off the selling price, we'll see

JGB1955

A system boiler still has a storage water tank....with hot water in it....

matelodave

Check the boiler spec - we had a Vaillant condensing boiler over 20 years ago, so it may well be  a condensing boiler even if it is old. The the vendor might be prepared to split the difference to get a sale.

Rodders53

20 years old is nothing for a decent system boiler.  A combi boiler, however, with no hot water tank is a different beast.
Boiler efficiency is not necessarily that poor 20 years ago - the Ideal Mini S24 in our last home (it would be 15 years old now) had a 78.3% specification and I was surprised to find it installed (not a condensing boiler).

You need to find model number of this V boiler and download and understand the spec of it.  You may not save that much on gas as you speculate, currently.

Also check out the EPC (spit) to see if the assessor had any clues about the building construction, floor area and how you could improve things (if at all).  A 4 bed detached dormer bungalow will likely have a very different footprint to a 4-bed semi or terraced house with greater external wall area.  Old enough it may have suspended timber floors with no insulation beneath, nor cavity wall insulation?   What age of build are the two (and the conversion to roof-space)? as Building Regulation/insulation requirement will have been different over time.

Energy (gas and electric) bills may be high due to other factors that differ from your current home.  (e.g. We have a Hot Tub, Air to air heat pump, and a rainwater harvesting system).  

I'd recommend living with what is there for at least one year before deciding if things need altering / renewing.

But if the energy bills thing alarms you and you have yet to exchange contracts it's not too late to withdraw.

st999

I used to have warm air heating and the hot water tank  was heated by a separate boiler with a pilot light 

The boiler was on all the time, there was no thermostat on the tank the only control was the boiler thermostat and I used between 16 and 20 kWh of gas a day for hot water and cooking, I eventually worked out that the hot water usage was about 11 kWh a day,

I now have a combi boiler and gas usage is just the same as before less what the pilot light burned.

So going from a hot water tank to a combi is not going to save much gas, if any, heating water.

Did save 4,000 plus kWh on the heating though.

andrewjf

JGB1955 said:

A system boiler still has a storage water tank....with hot water in it....

I know it does. But there's no supply water tank for the hot water cylinder.

matelodave

I guess there's a pressure vessel adjacent to the tank so probably got an unvented tank which is fed direct from the mains. There will be a three port valve which diverts the hot water from the boiler to either the heating or the hot water tank in the same way as any other system boiler.

welshmoneylover

Bungalows are expensive to heat as their footprint is much wider than a house irrespective of any boiler; the bills will always be higher than a house.

gg23

welshmoneylover said:

Bungalows are expensive to heat as their footprint is much wider than a house irrespective of any boiler; the bills will always be higher than a house.

It does depend on who the owners are and what they find comfortable.  My grandmother in her 90's was seemingly not comfortable with anything less than the approximate temperature of the surface of the sun, but the OP says they keep theirs under 20c which I find is probably a bit below average? The difference in heating a house to, say 19c and 24c is probably quite big, and of course, the OP simply says "energy" so presumably electricity too.  If they have incandescent bulbs and keep them on all the time, especially in hallways and the like that can quickly adds up.  Then there's how often they wash their clothes, if they have a vented tumble drier etc.