hot water into cold tank!

[AnonymousImport]

I recently purchased some bath mixer taps with a shower attachment (telephone type). The man up the road isn't a plumber, but kindly said he would fit them for me once I had choosen them. When he came to fit them he said he they were they may be the wrong type for a combination boiler and wouldn't like to fit them being unsure. He explained further that my hot water was mains pressure straight from my boiler and the cold was fed from a tank. The result may be that the high pressure would force it's way into my cold water tank when the shower was turned on. He asked me to find out whether this could happen and if so, is there a type of valve that could be fitted. I have tried ringing homebase and other plumbing centres, but they don't know either. I really don't want to put the nice man to any other trouble, so I would be very grateful if some one could help, I am disabled you see and really do need the shower.

 

[AnonymousImport]

you shouldn`t have a cold water tank if you have a combination boiler

 

[AnonymousImport]

Find someone who knows what they are actually talking about...and quick!

 

[bathroombob]

He is right in what he is telling you.
the combi boiler runs from the mains thus giving you high pressure hot water. The cold water fed from the tank has slightly less pressure so the hot water would force its way up the cold pipe and into the tank. go to the local plumbers merchants and purchase a single check valve and fit it to the incoming cold feed to the shower. this will allow the cold water out but not the hot in. I would also fit a thermostatic shower as this will regulate the temperature of the water, helpful due to the unequal flows.
It not uncommon to find combi boilers fitted and the cold water to the bathroom and wc supplied via a tank. Handy if they shut off the main.
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