Power Shower

[jsee]

Hi, a while ago I fitted a power shower with internal pump- the type suitable for gravity sytems. It's a Wickes Aquatronic Thermostatic. I've fitted it as per instructions but sometimes soon after switching on or when turning the speed of the pump up, the shower sounds like it's airlocked and doesn't emit any water you just get a fairly high pitched zzzzzzzzzzzzzzzzz then if I turn to cold and/or turn pump speed down it sorts itself out. It's usually okay provided the pump is turned up slowly and it's started in the cold position. My only explanation to this is the existing pipework which leaves the HW Cylinder in 22m then goes to a 22x22x15 tee. The 15mm is the vent pipe and goes horizontal (but slightly up) for a foot then upwards to the tank. As this vent pipe is AFAIK undersized could the system have difficulty venting and therefore causing the problem described. The hot water tap in the bathroom sink also splutters 10 seconds after start up too. Guess we'll never know 'cause I installed it for my ex-girlfriend but it would be interesting to know.

Thanks to any replies

Jon

[manatbandq]

You did follow the instructions for pumped showers and fit a dedicated hot supply from a flange on the cylinder, didn't you? I've yet to come across one that didn't have such instructions.

MBQ

[jsee]

Thanks for the reply. I did follow the instructions but there was no reference to a dedicated hot supply, a T into the hot pipe before other outlets is all that's required. I've got one in my own home, a New Team that's done in a similar way and that works fine.

Jon