Pressure problems

[waynes]

Just had a new hot water instalation, combi boiler in a small 2 bed bungalow.

Boiler is about 6m from mains and about 2 meters from the bathroom taps and 3 meters from kitchen taps, however the kitchen taps go up into the loft then down again for the combi (using 22mm pipe for the hot there too)

Problem is when the bath is running we dont get very good performance in the kitchen, when I say not very good I mean no water out the hot tap and very little out the cold, is this normal? is there anything I can do about this? or have the plumbers dun something a little wrong?

 

[chrishutt]

Combi boilers can only produce so much hot water per minute (typically10 litres for 24 kW combi, proportionately more for 28 kW, etc.).
If you have more than one outlet (tap) open, the hot water will take the easiest route.

Really your combi installers should have discussed this with you before hand. You might then have chosen a combi with a bigger hot water flow, or even one that stores hot water. As for 22mm pipe, this should not be used on the hot water supply pipework since it means that a large volume of cold has to be drawn off before the hot comes through.

Did you ensure that the installers were Corgi reg.? Did they fill in the "benchmark" form (which should give details of hot water performance)? Was it a condensing boiler? Have you had letter from Corgi to confirm installation made by registered installers?

 

[waynes]

They are corgi registered, havnt had a letter from corgi or a benchmark form filled in (admitidly they only finished beging of this week)

The 22mm pipe is original pipework (Bungalow is 1950ish) and yes its a condensing boiler.

I was under the impression it would be reduced but not none existant! ah well, not too much of a problem as there is only two of us and i'm sure we will get used to it, from what Ive been told the pressure here in Cambridge is poor so that dosnt help.

I take it I should expect to see something from corgi in the next few weeks?

 

[chrishutt]

In theory the installers should notify Corgi of the installation, who will in turn (1) notify Building Control (of your local authority) as required by law (building regs. Part L) and (2) send you a letter to confirm installation by Corgi installer.

In practice I doubt whether your installers will bother, if they haven't bothered to fill in the benchmark certificate, which is also a legal requirement (I think) under building regulations.

The lack of documentation may possibly cause you difficulties if you need to have the boiler repaired under guarantee or when you sell your house.

 

[waynes]

Thanks for your help,

Will chase them for the documentatioin