Annoying shower pump job.

[europhil]

Please be gentle, I'm new to this forum. and thanks in advance for any advice.
I've had a customer ask me to replace a shower pump, The one they have is an Aquilisa 1.5 bar twin impellor.
So i priced it up, Then went round to fit the replacement.
He wasn't happy as the pressure hadn't increased. The thing is, He didn't ask for a bigger pump, Just a replacement.
I've checked his old pump, and apart from a bit of a cleanup, It's in pretty good shape.
So to keep him happy i've had an idea.
I use both the old pump and the new one by teeing the cold feed to both inlets of one pump, and the teeing the hot feed into both inlets of the other pump. Therefore i'm using both impellors of both pumps for each feed.
What do you think? Will it increase the flow? Or will i be wasting my time?

 

[rocketmanbkk]

Can I ask what you charged to fit a new pump? Did one today and trying to get a feel for prices. My job was a straight swap and customer ordered pump which I found. Cheers.

 

[europhil]

£270 including labour and pump. It'll be 90 miles by tomorrow. I wish i hadn't bothered.

 

[tackleburger]

I'd be a bit cautious running the pumps in parallel, one for hot and one for cold unless the shower is a thermostatic one. Otherwise, if the cold failed for some reason, you'd be pumping hot only to the shower, with a risk of scalding. With a single pump if the flow fails the pump shuts down both cold and hot.

The shower may shut off in the event of hot or cold failure which would stop the pumps? I wouldn't do it take the pump back get a refund as its faulty and say you bought one nearer the job to save time. Get paid walk away. I don't think the double feed on the pump will make any difference the pressure is equal all your doing is doubling the input water then halving it again at the shower if you think about splitting a cold main you don't get half the flow at each tap you get what the main is capable of giving you and as long as the pipes can take it your fine. So if the pump is givi g you 20 litres a minute max a 15 mm pipe will handle that so two pipes coming out the pump ain't going to make it anymore. He'll not be happy and probably moan about the noise as well.

 

[mfgs]

Maybe I've got my head on back to front, but I would expect 2 in parallel to increase the flow (subject to the pipe sizes being big enough) but not the pressure?

I agree with ray, two pumps designed to pump to 1.5bar will still only pump to 1.5bar.