worcester-bosch 24i combi boiler

[gerryg]

now got a problem with my shower after having the above boiler installed.
before getting boiler installed i checked with shower manufacturer to make sure it could be used with a combi boiler, they and the boiler installers said this would be ok as long as it is " balanced correctly" whatever that means.
Shower has never really been right, seem to have trouble getting any hot water through it, the hot water does come but then goes cold again for long periods of time.

Does anyone have any idea what may be wrong.Should I be calling out the company who installed the boiler? Any info would be gratefully received.

[kermit]

What type of shower is it? It should be a thermostatically controlled mixer type. The main problem with a combi boiler is the hotter the water gets the lower the flow rate through it. If you can give any more info I might be able to help more.

[gerryg]

thanks for reply.the shower is a Bristan Collonnade. To be honest it seems to have corrected itself, dont know how, but definitely better than it was, maybe the pipes needed time to adjust or something. Dont know if you are heating engineer but another slight problem is that when the boiler starts up there is a low vibrating sound coming from it.this settles down once the heater is up and running. The low vibrating sound( it wakes my daughter up) stops if i lightly put my hand against the casing of the boiler.It is obviously caused by some pipe or valvue within the boiler vibrating against casing.
Should I get the heating engineers out who fixed the boiler to have a look at it, or is there something simple I can do, as it stops as i said as soon as i place my hand on the casing to stop the vibrating.

Any info much appreciated.

[kermit]

Hi, sorry for the delay in the reply. Been mad busy. Bristain are one of the better makes of showers, I've not fitted your model myself and can't find it on the bristain web site. A common problem on the temp side of things is the temperature regulator may not have been set or could have stuck if the problem has corrected itself.

Another problem could be if the combi was fit to replace an old system of an indirect boiler and hot water tank. The pipe size for the hot water side of things in the bathroom would be 22mm. This would aid the gravity feed. The combi gives hot water at near mains pressure so 15mm is adiquate to maintain the pressure. 22mm could cause some pressure drop but hopefully the shower is a pressure regulating one to balance the hot and cold.

The vibration of the boiler sounds like the outer case may not be located properly or on quite square. There only fixed by locating on clips at the back and a couple of screws for fixing on the front behind the drop down panel.

Hope it helps.