Reduced water pressure

[lawsthedoors]

Hi guys, I have a shower running from a combi boiler that is slow when another tap in the house is used.
Is there any way I can keep the flow constant ?

 

[Simon F]

what size is the combi boiler ( what kw rating ) ?
is the shower upstairs ?

a small combi, 24kw will only give around 9 lt flow of water, ( per minute )
so if another tap is opened you will always struggle.

 

[jtsplumbing]

Whats your water pressure like ??

 

[Bernie2]

The problem's usually stem from water main pressure and flow and combi output flow. Basically as Simeon says the bigger the combi the more flow. But only providing the water main can deliver the flow and pressure rates required by the combi to the combi.

So basically you have to check the main out first, to ensure the combi is getting enough of both to give its full output. If it is, then you may have the problem of having too small a combi which you can do little about. But if you check the combi output and find it is delivering enough to provide the showers requirements while overcoming any pipework resistances, then obviously the problem may be with the shower.

But just off the record its probably the combi flow rate or the main, its quite common for it to happen and although it is a nuisance the alternative is to get a bigger combi. which usually means lots of money.

 

[SimonG]

I would say one of two options. Bigger combi with an increased hot water output or don't open the tap when in the shower.

 

[lawsthedoors]

thanks for the info

 

[lawsthedoors]

thanks for all the reply's

 

[zzzjim]

Fill the kettle up before a shower , and leave some warm hand wash water in the bowl ?

( Some house members may enjoy this negative feature )

 

[steadyon]

If it is one tap in particular, you could consider installing a flow limiting isolation valve just before it. Won't cure the problem if it is an overall lack of pressure / flow, but might make it tolerable by limiting the amount of water diverted to the tap. Of course it will permanently limit the flow at the tap, which might be a different problem in itself. Look up Arrow Valves on the internet for an example.