Hot water runs slowly after a few minutes

[fingres]

We've had a problem for a while now where the bath will only fill a few inches before the hot water turns to a trickle. I usually leave it a while and try again. Anyway, tonight I decided to take a closer look.

We have an indirect system. I'm not sure if it's vented or unvented. We're in a flat with no roof space, the top of the hw tank disappears higher than the door frame into the airing cupboard so I can't get at it.

I thought it may be an airlock or blockage, but realised the bathroom and kitchen taps all suffered the same symptom. I also realised I couldn't hear the whooshing noise of water filling up the hw tank. I closed an re-opened the valve on the cold feed then heard the whooshing.

Now the valve turns easily, but feels damp and seems to have a slow drip. I'm guessing the valve needs replacing and could have been the cause of the lack of hot water. Is there anything else it could be I might have missed?

Cheers!

 

[ChrisOxford]

The valve's probably dripping from its spindle merely because it's been used after a long period of inactivity. Annoying, but not the cause of your fault, I suspect.

Your hot water cylinder will probably be filled from a cold water storage cistern, either a separate unit or sometimes actually attached to the top of the hot water cylinder. Investigate that, i.e. check that it's filling properly.

C.

 

[fingres]

Thanks Chris. I wondered about this, I think the cistern must be attached to the top of the HW cylinder as there's nowhere else it could be in the flat.

I'll investigate tonight and see what I can find.

 

[ChrisOxford]

Known as a "combination tank", I think (not to be confused with a combination or "combi" boiler, of course!).

 

[tincup]

Hi

My opinion would be a blockage around the tank h/w outlet or the pipe off of it. Likely caused by limescale.
I would also check the level of water in the header tank and that the ball valve can keep up with the h/w output.

HTH