Impeller pump.

[NANUK]

Evening Guys
I've just bought a Wickes impeller pump for my shower. In the write up it says I must use 22mm pipe to feed this pump. How important is this? as I have inherited 15mm pipes that are in situ .
I thought I could just use reducers from the pump hoses to fit onto the existing 15mm pipes.
Thanks.

 

[gas4you]

Always install to M I's. It must need 22mm for the volume of water it wants to pump.

 

[joshmcfee]

Evening Guys
I've just bought a Wickes impeller pump for my shower. In the write up it says I must use 22mm pipe to feed this pump. How important is this? as I have inherited 15mm pipes that are in situ .
I thought I could just use reducers from the pump hoses to fit onto the existing 15mm pipes.
Thanks.

You'll invalidate the warranty because these pumps are designed to have a throughput consistent with speed,i.e. you'll damage it.
As the other guy says,always work to the manufacturers instructions.

 

[Nige F]

Cavitation

 

[NANUK]

Thanks guys, it looks like I've got some new pipework to fit! better than a pump that won't work though in it!

 

[ChrisR]

I wouldn't be quite so hasty.
How long are the 15mm pipes, and how are they plumbed - the configuration's more important.. All the pump sees is a resistance - a long bit of 22mm has resistance.
What pump is it?
I had a 1.6 bar pump on about 5m of 15mm for 16 years...

 

[NANUK]

It's a 1.2 bar from wickes.

There would be approx 2m of 15mm pipe to the cold inlet and .5m of 15mm to the hot inlet.

Both outlets would take 1m of 15mm,

Everything exists in the airing cupboard, with the cold tank above in the loft.

What do you reckon?

 

[ChrisR]

Depends where the 15mm pipes are connected to , and the diameter and length of the feed to the HW cylinder, and CW from the loft cistern.

Like I said...
- the configuration's more important..

 

[NANUK]

OK , Hot 15mm connected to 22mm pipe from top of hot water cylinder.
Cold 15mm pipe connected to 15mm pipe from cold water tank in loft.
Connections are in airing cupboard.

 

[Agile]

Well thats a very simple job to replace with 22 mm and everything will be fine!

Amusingly in some situations with long 15 mm feeds just replacing with 22 mm improves enough not to need a pump!

Tony