PUMP HOT & COLD WATER TO WHOLE HOUSE

[bobandlel]

Hi everyone. I need some advice.

I have put in a new shower and purchased a Stuart & Turner 3 bar pump to boost the hot & cold to the whole house. I have planned the plumbing and just want some advice on if i an right.

I have a open vented CH, i have fitted a salamander HWT top entry valve to connect the hot to the pump which will pump the hot water to the shower with a Tee off to the hot water pipe which supplys the whole house.

The cold water will be supplied by the CWT in the loft and the taps the same as above. My question is do i still have a overflow pipe running back to the CWT in the loft.

 

[Jinxy]

If you had one before then I cannot see a reason for it to disappear because you have fitted a pump from your cistern.Your pump will only last as long as your tank is full which is a relatively short space of time if you have more than one power shower/bath etc. Unvented is the way to go. hot water at mains pressure, marvellous...By the way, dunno your setup but I wouldn`t be pumping my cold feeds to outlets from tank as well, I`m sure you have got this wrong somehow or I have misinterpreted what you have posted but your cold supply needs to be fed via your cold main from outside not via a tank, your shower or showers will be tank fed via a pump hot/cold., The rest of your cold supply should be mains fed.

 

[bobandlel]

Hi
Just to say thanks for the reply.

The cold water to the taps is mains fed at present, as the pump is a hot and cold pump just thought i had to pump both. So is it ok just to pump the hot only which will give me better pressure which is required.

 

[GrahamT]

My understanding of this post is that he is talking about the vent pipe. You MUST have the vent pipe still terminating over the cistern. I have come across diy pump connections before where they have failed to reconnect the vent - very scary

If in doubt get someone in who knows.

If I have the wrong end of the stick and you are not talking about the vent pipe then apologies not sure what overflows go back up tho??

Graham

 

[bobandlel]

Hi Graham,

Yes i was talking about the vent pipe which goes back to the CWT. My main question is can i just pump hot water to the taps off the pump or do i need to put in a single pump to do that.

 

[GrahamT]

You can get a single whole house pump to pump the hot taps. Be careful, if you have cold mains on feeds to mixer taps, shower valves, you'll need to get a negative head pump

 

[GrahamT]

Hang on, just re-read your post. I'm confused? you already have the pump. Is it a twin pump? what are doing with the cold?

 

[bobandlel]

Hi Graham.
Yes i have a twin pump which is used for the shower. But have very poor presure to the hot taps so can i use this pump to the shower and only use the hot side for the taps.

 

[Gasguru]

You can only pump hot or cold on its own providing the pump is designed to do this. Pumps designed so, have bypass arrangements within the impeller housings. If you use a standard pump and only pump one side the water within the closed end will undergo significant expansion as the water is churned due to frictional heating. The expansion can result in sufficient pressure rise to cause seal failure. Short water drawoffs and you may get away with it but don't bank on it.

And you must always have the safety vent pipework plumbed in.

 

[bobandlel]

Hi
The pump i have is a Stuart & turner 3bar monsoon standard twin pump.
Would i need to buy a negative head pump?

 

[GrahamT]

Hi
The pump i have is a Stuart & turner 3bar monsoon standard twin pump.
Would i need to buy a negative head pump?

Originally, I thought you were talking about just pumping the hot. If you had cold mains on mixer taps, you may not get the flow rate to activate a standard pump on the hot, so it's recommended that you get negative head.

 

[GrahamT]

OK, so you have a shower only, pumped on the Monsoon

Are all your other taps (except kitchen cold) fed from the tank?

If so, the monsoon is designed as a whole house pump. You can connect the pump to the main distribution to the house hot (via the flange) & cold.

If, however, all your colds are on the mains, then you will may have problems with the flow rate to activate the pump, thus a neg head pump is recommended.

 

[bobandlel]

Hi Graham,

Thanks for the help.
Think i am getting there.
The taps in the house are all mains feed.
Should i just buy a single pump for the hot then or pump hot and cold around the whole house with the twin?
The mains is just under 3bar pressure.

 

[GrahamT]

Am I to assume the shower cold is mains as well?

If so, then you will just need a single negative head pump for the whole house hot supplies.

Regards,

Graham

 

[bobandlel]

Hi Graham

The shower cold feed is from the tank which is pumped with the hot by the twin shower pump.