Pipework questions.

[DaG]

Hi all.
I'm after some advice about fitting a twin impeller shower pump.
The pump is installed in an upstairs airing cupboard level with the top of the hot tank & will be connected to the tank via a surrey flange. I've put in an anti gravity loop to drop the supply from the flange down about 250mm which the pump manufacturers recommend.
The hot & cold pipe work from the pump to the shower mixer has to go up into the loft, along the loft floor about 1metre then down into the bathroom.
What i want to know is do I need to fit auto air release valves in the pipework in the loft where the pipes run along the floor. I was told it is a good idea to fit them but would like other opinions.
Also at some point I have to change from 22mm pipe (from the pump) to 15mm to connect to the mixer. Does it make any difference where I reduce down?
Thanks.



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[310]

their no need for auto vents let the pump do the work ,its ok to reduce to 15 mm to connect to shower

 

[PlumbBobBob]

you can change to 15mm wherever you want after the pump really

 

[DaG]

Thanks for the replies they are appreciated.
I've now done 90% of the work & am in the process of fitting the Surrey flange. I've hit a big snag because the threaded boss on the top of the tank appears to be moulded into the tank. I can't remove it so can't fit the surrey flange.
What other options do I have other than change the tank?
Can I tee off the hot water feed pipe that comes out of the top of the tank, very close to the tank or will this cause air getting to the pump problems?
Thanks again.

 

[310]

yes u can tee off ho****er near clyinder all will be ok

 

[DaG]

yes u can tee off ho****er near clyinder all will be ok

Took me a few seconds to work out what the asterixs were hiding.-)
Is teeing off the HW a dirty word in plumbing circles?
I was toying with getting an essex flange tomorrow but it would certainly be less work to tee off the HW.

 

[Dannypipe]

Are you certain its moulded to the cylinder and not just surounded in foam insulation? Apparently you can tee off the top of the cylinder, but there are strict rules. I've always fitted a Surrey flange so can't remember the details.

It did get spelt out on this very forum once, but I'm not sure where the thread is now.

 

[Dannypipe]

I can't find it, but here you go. Here's a picture. I knew it had to be angled.

 

[Dannypipe]

For more info, follow this link. With that I'm off to bed.

[DLMURL="http://www.bathroomexpress.co.uk/pumps/tp60_inst.htm"]TP60 Shower Pump Installation Instructions - Bathroom Express UK LTD[/DLMURL]

 

[Best]

Took me a few seconds to work out what the asterixs were hiding.-)
Is teeing off the HW a dirty word in plumbing circles?
I was toying with getting an essex flange tomorrow but it would certainly be less work to tee off the HW.

Don't fit a Essex flange. They leak sooner or later, especially when fitted high on cylinder, as hotter there. They are stupid & unnesssesary - they are s**t, (& I think you can work out that word! ). Do it other methods. :santa5:

 

[DaG]

Are you certain its moulded to the cylinder and not just surounded in foam insulation? Apparently you can tee off the top of the cylinder, but there are strict rules. I've always fitted a Surrey flange so can't remember the details.

It did get spelt out on this very forum once, but I'm not sure where the thread is now.

Yes, the foam was right up to the threads & when i cut it back a bit to get a spanner on I found nowhere to put a spanner.
I was just heading out to buy an essex flange, but after I checked this thread I'm not sure now. Best says they leak & your angled pipe would be difficult to do because of the current pipe layout & restrictions in the cupboard that the tank & pump are in.
I'll have another look at the job & probably take the easy route - leave it till another day. [

On the link you posted it says......

An Essex Flange with AGL MUST be used when the pump is mounted ABOVE the hot water cylinder

What does AGL stand for as my pump will be mounted above the cylinder? The pump feet will be flush with the top of the cylinder.

Just realised it's anti gravity loop, I'm slow today.

 

[DaG]

Hi again.
I've now installed the pump, didn't use a conventional flange though. I bought a new immersion heater blanking plug, holesawed a 22mm hole in it & soldered a length of 22mm pipe into the hole. I made the pipe to go about 100mm into the tank so it picks up HW at about the cylinders seam.
The shower works great but I do have one problem with it. The pump starts to work in short bursts if anybody runs HW off anywhere in the house. What I mean is when nobody is using the shower & the shower valve is fully closed, running off HW elsewhere activates it in short sharp bursts.
Closing the valve on the HW input side to the pump or turning off the power to it is the only way to stop it from doing this.
Any help gratefully received, thanks.

 

[PlumbBobBob]

you need to put a non return valve on the hot feed from the cylinder to the pump.