Combi boiler hot water problem

[stevewood]

I have recently installed a Worcester 28 SI in a 3 bed semi (in the loft). I connected to the existing hot & cold pipe work (22mm).
The problem is that when the bath tap is running, it is not possible to run the basin tap at the same time.

Does anyone have any advice on how to rectify this problem? (I am pretty sure that is just the way it is due to mains pressure - but am having problems convincing the customer, who is not happy with the way that it works). Is there anything further that can be done?

 

[Bahco]

Which taps will not run at the same time?
Both hot taps in bathroom will obviously not run due to the nature of a combi and you will get reduced hot flow when you open a cold tap.
Clarification please

 

[corgiman]

prior to fitting said combi did you check that pressure and flow from the mains supply was adequate, cos if it weren't your kn''''kerd

 

[bripl]

28si will only deliver around 13.5 litres at 30 degree rise or 10 litres at 40 degree rise these figures relate to the 28si two check the flow regulator is clear.you will have poor performance due to where you have connected the hot water if i have read your post correctly

 

[oilman]

mmmm..........fancy finding a problem like this with a combi, who would have thought it?

 

[ChrisR]

Steve are you corgi reg? Installers learn early on about water pressures....

 

[DP]

Chris U beat me to it

 

[bripl]

hold on what on earth does corgi reg have to do with the prob?unless i am mistaken corgi only means you are competent to work on gas this is a hot water prob,if the appliance is fitted to the manufacturers instructions and the bench mark is filled out and the boiler commisioned correctly.whats the prob,i would be more inclined to question his competence in plumbing/heating than gaswork.too many people have corgi registration without the knowledge/understanding of how a heating/plumbing sys works.how many people post on these forums questions about combis?the majority soon find out combis are not really suitable for their needs,this is why we need to address the question of competence in the plumbing/heating industry,any fool can get corgi you only have to see the forums to realise that[gets off soapbox and heads for the nearest deep shelter to avoid all out war]

 

[Bahco]

I got the same impression as Chris that maybe poster was a diy installer as a bona fide installer would know the nature of the combi beast and explained it to the client prior to fitting.
Hope he gets paid

 

[corgiman]

Totally agree with the above

it always seems to me that combi's are a piece of piddle to install they get put everywhere

I would say that 6 in ten combi that I see have been put on and inadequate mains supply and the client is moaning about poor performance

Combi's are NOT a cure all boiler, they are great when everything is right but a total b'tch whe they aint

 

[PEDANTICVINDICTIVEMAN]

This is why after verbally telling my customers of the fors and againsts of a combi, I always put the following on my quotes-

*Hot water flow rate at the taps as specified by Worcester for the xxxCdi but max flow rate dependant on incoming cold mains pressure, existing pipe sizes and how many taps open simultaneously. If you have any queries of any kind please contact me. You can visit the website www.worcester-bosch.co.uk for more information.

 

[stevewood]

Firstly, thanks for all the responses... much appreciated.

Secondly, I am corgi registered & a professional installer. But in this instance, the customer dictated that I had to install a combi boiler, didn't want any advice & claimed he had a combi boiler before so knew all about them.

Of course, when the job was completed, & he then found that he could not run the bath & basin taps at the same time, he would not listen to my explanation of the mains pressure & how combi systems work.... instead ranted on about the installation not working as he thought it would work.

So, thanks for the back up - I intend to show him some of your comments to prove that it is not just me feeding him a load of b*llocks!

 

[jillybug]

Dear Steve

Please help me. I was changing the time settings for the boiler to come on and all of a sudden the boiler went out. finally came on - dont know how or why but no the light for the hot water wont come on. I inherited the boiler with the house when I moved in recently. The previous owner(who claimed to be a plumber!!!) must have been called Roy Rogers!
Also can you please advise me how to re-light the pilot light and what is the small red button on the front of the control panel in between the lights for the radiators and hot water is for.

Would appreciate any help you can offer - Thanks.
J x

 

[PEDANTICVINDICTIVEMAN]

Is this a piisstake question or what

 

[COG]

What is the model of the boiler ,your discription sound like a 24/28 cdi not a si ? ?