cold but not hot

[newhousemadness]

I have just fitted a new bathroom with many problems but finally all fittings are in bath, sink, shower and loo.

Problem is I have ample supply of cold water but the hot water flow is very weak.
The cold is fed from the mains, the hot is fed from the tank in the attic.
the pipes from the hot tank are 22mm and were lead piping which i replaced with 22mm copper piping. I took 15mm to the sink and bath, please can anyone help me.

 

[Nige F]

Should be 22 to the Bath..15 to the Basin and sink in kitchen..on the hot. Hope you put a 22 vent from the cyl up+over the cold supply tank in roof.

 

[ChrisR]

If it's really really weak you probably have an air lock. Push it up with the cold mains.

 

[newhousemadness]

I didnt touch pipes in the roof the lead finished in a cuboard and unfortunately I do not have a cold water tank (sorry house a bit dated) The cold is directly from the main.

How do I push up from the mains

I sounds very painful

 

[slippyr4]

I didnt touch pipes in the roof the lead finished in a cuboard and unfortunately I do not have a cold water tank (sorry house a bit dated) The cold is directly from the main.

so what do you have in the loft? A conventional system would consist of a cold storage tank up in the loft, connection to a copper cylinder, usually in the airing cupboard. The cold storage tank doesn't necessary feed anything except the hot water cylinder.

 

[Gasman1015]

The cold is fed from the mains, the hot is fed from the tank in the attic.

The hot supply should have a 22mm pipe going up to the tank for expansion of your hot water.

 

[newhousemadness]

Sorry if i am confusing you
The tank has a cold water storage but this does not feed any of the cold taps sorry plumbing isn't my thing.

The piping is 22mm from the tank into the bathroom and i have fed from this to the basin,bath 15mm.

22mm then carries on downstairs.

If it is a airlock can anyone explain how i clear it

 

[Nige F]

Hi, Just connect a cold tap to a hot tap and turn on hot then cold.which is mains..use a bit of hose. the mains water then pushes back up the hot and should clear the air. Kitchen sink ,or basin will do. Sprays out a bit unless you can rig a hose commector to each end . Or across H+C washingmachine connections