Hot Water Trickle - Advice please

[Ian500]

Hi, I've recently moved into an old house with even older plumbing and electrics. Since moving in, the hot water pressure through taps at all levels has reduced to a trickle. The shower is powered by its own pump - to supply higher than average pressure to the unit upstairs - and even this is struggling to provide enough hot water to supply a five minute shower (after this it just dries up). The system is gravity based - I think - and is supplied by a boiler and pump on the lower level. The radiators all appear to work well and there doesnt seem to be any obvious leaks. I've discovered that the pump under the boiler - a Grundfos Selectric UPS 15/50 is corroded at the pipes and there is evidence of previous leaking (although this is now very dry). The unit also appears to be installed upside down. Can anyone suggest reasons for the lack of hot water pressure and possibly suggest a proper order in which to attack the problem. Many thanks - much appreciated. Ian

 

[Softus]

Do you have a cylinder fed by a cold storage cistern?

If so, how quickly does the CSS refill when you're running hot water off?

 

[Nige F]

Hi, I've recently moved into an old house with even older plumbing and electrics. Since moving in, the hot water pressure through taps at all levels has reduced to a trickle.

So it WAS alright to start with .........Look in roof cistern for dead pidgeons,or stuff blocking the outlet to the hot tank

 

[Ian500]

Hi Softus and Nige, thanks for your replies. The hot water pressure has always been poor but it recently got worse. Right now, after a 20 second trickle it dries up completely when one of the taps is turned on fully. The shower, which has an independent pump, manages to supply hot water via the mixer for about 7-8 minutes before the hot supply runs out. There is definitely hot water in the cylinder. I've looked at the cold storage cistern and there doesnt appear to be a blockage to the cylinder outlet. Besides some limescale build up on the ball-cock the system seems to be working OK. When cold water is drawn off by the hot water cylinder i.e. when the shower is on full, cold water is being supplied immediately into the storage system - but it takes some time after the shower is switched off to fully fill. In others words, the cold water isnt being replenished as quickly as its being drawn off. That said, theres plenty of cold water in the storage cistern and I cant see any problems with cold water supply to the cylinder. Any thoughts? Thanks again..

 

[Nige F]

OK the plumbing is old ...but is it all copper?....and is the storage cistern in roof plastic or grey cement type or fibreglass..........or rusty galvanised steel Are all the taps slow running .......are you Sath of the river

 

[tincup]

Hi


Sounds like the cold water feed to the hot storage tank is partially blocked or the gate valve not open enough.

One final point, whats the size of the pipe work feeding the hst?


Hope this helps.