Boiler power

[apcdave]

Was at a property the other day -fairly large - approx 68 square meters on the ground floor and 59 on first floor. Gas combi - Jaguar 23kW.

The punter asked if I thought this size of boiler was adequate for the size of the property - I replied probably but unsure

He has had all the rads on in the house and they are all heating but " one or two possibly not as hot as he would like "

a little vague I know but any thoughts?

cheers,

dave

 

[stevetheplumber]

Was at a property the other day -fairly large - approx 68 square meters on the ground floor and 59 on first floor. Gas combi - Jaguar 23kW.

The punter asked if I thought this size of boiler was adequate for the size of the property - I replied probably but unsure

He has had all the rads on in the house and they are all heating but " one or two possibly not as hot as he would like "

a little vague I know but any thoughts?

cheers,

dave

give us an idea what the property is square metrage means nowt to most of us three bed?four bed?semi ? detached ? 23kw is quite a high heat load so should be enough to heat most houses that dont fall into the mansion catagoery ten or twelve rads assuming some will be small ones
more likley to be a balancing problem

 

[doitmyself]

It all depends on the type of house, construction and location.

An 8m x 8.5m two storey detached house with solid walls, single glazed windows and no loft insulation in Scotland will need about 22kw to heat. The same size house with cavity insulation, double glazed windows and fully insulated loft in SW England will need 8kW to heat.

The whole house boiler calculator will tell you what he needs.

However, it does look as if his boiler is big enough and the only problem is that the system is not properly balanced.

 

[david williams]

or properly piped the amount of systems [even large ones] i see where predominatly 15mm pipework has been used

 

[doitmyself]

or properly piped the amount of systems [even large ones] i see where predominatly 15mm pipework has been used

Using 22mm when 15mm is OK is just as bad. It all depends on the amount of heat the pipe has to carry and the flow rate. Too fast a flow = noise, too slow = sludge build up.

 

[apcdave]

Thanks guys - it's an end terrace with extn built at side and rear. 5 bedrooms , large kitchen/diner and 2 lounges.

The original property is solid wall and the larger extn is cavity constructed in 2000. Mostly double glazed.

 

[Bernie2]

Google and get a copy of Stelrads STAR program.

Put in info and it should tell you. Its not bad perhaps a bit high but okay. Saves all that mucking about.

 

[doitmyself]

Thanks guys - it's an end terrace with extn built at side and rear. 5 bedrooms , large kitchen/diner and 2 lounges.

The original property is solid wall and the larger extn is cavity constructed in 2000. Mostly double glazed.

Then use the Whole house boiler calc I gave a link to earlier. It does not ask any complicated questions.

Treat it as three parts, e.g: main house with one external wall (front); rear extension with three external walls; side extension with three external walls. Add the results together and then deduct 6kw (3 x 2kw hot water allowance).

 

[flat pack]

if it worked before it should work now.balance the radiators by closing down the rads nearest to the boiler ,turning the return valve clockwise to reduce the flow thus increasing the flow further down the line.
Also check for any by pass valve below the boiler, or sometimes in the bathroom

good luck mate

 

[the_ace]

Anyone know what the Jaguar 23kw combi is based on? I think its a glow worm or a saunier duval