"TR" wrote in message
...
Hi everybody,

I was wondering if I could use a single pump to boost pressure for
cold water only. I have hot water of ok pressure coming from a
combination boiler (which itself is fed by mains), but cold water for
the bathroom is coming from a cold water tank in the bathroom (the
bottom of the tank is barely higher than 4 feet from ground and if you
hold the shower head higher than that = no cold water at all.

Now my idea was to use a single pump with negative head functionality
to just boost the cold water, hoping it will nicely mix with the
ok-pressured hot water and I will finally be able to have a shower...

Any ideas, recommendations, etc ?

Thanks

TR

As you no longer need a cold water tank (should have been disconnected when
you had combi put in), wherever the two pipes are closest, your feed to the
tank and the return, cut and join, thus removing the storage tank from the
system.