pumped hot water

[jamesboy678]

young lad just qualified as plumber and have been asked by a mate to sort his hot water out.

he lives in a single flat no upstairs and has a gravity fed system. the hot water is indirect fed and feeds one basin tap, one kitchen tap, mixer shower and bath tap. the flow rate is extremely poor due to the head pressure being ridiculously low. he has asked me if i can install a pump to help out with the hot water. has anyone got advice on how i would go about deciding what pump to use and how i would go about the job?

any advice much appreciated

 

[charlie frederi]

young lad just qualified as plumber and have been asked by a mate to sort his hot water out.

he lives in a single flat no upstairs and has a gravity fed system. the hot water is indirect fed and feeds one basin tap, one kitchen tap, mixer shower and bath tap. the flow rate is extremely poor due to the head pressure being ridiculously low. he has asked me if i can install a pump to help out with the hot water. has anyone got advice on how i would go about deciding what pump to use and how i would go about the job?

any advice much appreciated

Hi
I would fit a stuart turner negative head pump single impella for the hot and put the
cold on the mains

 

[jamesboy678]

thanks very much for the reply, i will look into that. also im i right in thinking that the pump should be placed after the vent pipe to avoid pumping over the vent?

 

[moony]

thanks very much for the reply, i will look into that. also im i right in thinking that the pump should be placed after the vent pipe to avoid pumping over the vent?

i would personally come straight out of cyclinder using an essex flange.

also i would think twice about using a pump on the hot and mains pressure.... i would personally pump both the hot and the cold from the cylinder and cwsc respectively to ensure equal pressures.

 

[jamesboy678]

the flat is very small as well, and my mate aint short of a few bob. he has been complaing about the state of the flat for long time and i was thinking would it be an option to maybe install a unvented system in the flat? that way the cold and hot are balanced. i have my unvented hot water ticket so installing it would be ok for me to do

 

[moony]

go for it mate. expensive bit of kit though.crazy how you need to know how to fit a pump but you can fit unvented crazy how these qualifications work.

 

[newbie1]

listen out for a unvented cylinder going into orbit soon

 

[secret squirrel]

If your fitting your unvented cylinder, I'd re-read all your books, read the install guides twice, have a look at the property twice (at least) you'll see things you missed the first time, if you think it'll take a day it'll take 2. Think about where all the pipe works going, re-check everything before commissioning, have the cylinder help line programmed in your mobile just in case. Maybe being over cautious but this is what I do. Good luck.

 

[charlie frederi]

i would personally come straight out of cyclinder using an essex flange.

also i would think twice about using a pump on the hot and mains pressure.... i would personally pump both the hot and the cold from the cylinder and cwsc respectively to ensure equal pressures.

Hi

that is right about the essex flange and i agree about putting both feeds on the one pump that is providing the ballvalve can keep up with it
have done that in similar situations and the ballvalve could not cope
so had to use pump for the hot and blank the cold on tank joining to the mains which works perfectly well and has for the last five years.
also depends on mains pressure as most likley between 1 & 2 bar
which i am pretty sure a pump runs at

cheers

 

[moony]

well some of these showers fitted can be expensive and a thermostatic head being about 60-70 quid plus labour - i would prefer to make sure the hot and cold were equal pressures... have never fitted mains onto a pump before as it can invalidate the warranty on the pump too if not fitted to manufacturers instructions - im not saying it wouldnt work charles me old mate - but its not something i would do myself.

 

[charlie frederi]

well some of these showers fitted can be expensive and a thermostatic head being about 60-70 quid plus labour - i would prefer to make sure the hot and cold were equal pressures... have never fitted mains onto a pump before as it can invalidate the warranty on the pump too if not fitted to manufacturers instructions - im not saying it wouldnt work charles me old mate - but its not something i would do myself.

HI mate
Think may u have miss understood i would never fit mains to a pump unless it was a booster pump on a high rise building.
i simply stated using a single impella neg head pump on the hot and changing the cold supply to the bathroom to mains pressure

 

[moony]

would that then make the both pressures equal though ?

 

[charlie frederi]

would that then make the both pressures equal though ?

Depends what the mains pressure is
if you are talking about a shower you can use pressure reducing valves.

Or there is a shower on the market that has mains feed and hot feed with no pump trevi boost and a shower is the only place you would want equal pressure?

 

[moony]

yeah i know of the trevi never come across one though.

yeah thats all i was asking charlie, a prv would have to be used, therefore i would personally use a pump on the cwsc for cold and hot cylinder no need for the prv then. But i see what system you would use - charlie im only on my level 3 myself in heat and vent so look for different ways of doing things and all views are welcome - more i know the better.

cheers

 

[still learning]

what ever pump you may choose just be sure the cold water tank feeder is big enough to not get sucked dry by pump, also, use proper flange on top of cylinder to save sucking in air, hope this helps omigo