Hot water flow initially very very low then its normal

[alodo]

A recent problem has come up with our plumbing. The hot water flows very slowly from all faucets, then after a minute or so the hot water flow goes back to normal and then runs at a decent flow. Process repeats when hot water has not been used for a while.
Any ideas what might be causing this?

 

[rojaca]

Potterton puma?

 

[alodo]

The boiler is a Worcester Bosch thermo technik 35DCDi

 

[mickyg]

maybe you've got a non return valve somewhere opening slowly?

 

[alodo]

maybe you've got a non return valve somewhere opening slowly?

Is there any way to figure out whether this is the problem without cutting up all my pipes and replacing them all?

 

[Agile]

Best to get an engineer!

If you want to DIY then you could disconnect the boiler DHW output pipe and see what it does to that point.

Tony

 

[alodo]

Best to get an engineer!

If you want to DIY then you could disconnect the boiler DHW output pipe and see what it does to that point.

Tony

Not up for that sort of diy Thanks, at the moment the system does work after a minute, and sometime it even works straight away so will leave for a bit and see if any other symptoms pop up.