Pump Issues . . .

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Hi Guys,

I just wanted to bend a few of your ears about something I have not come across yet!

I am replacing a nice Stuart Turner negative head pump (no problems there usually!)

Having said that this pump is very old and has an extremely weird set up that I have not come across before as It looks like it has expansion vessels attached to the pump body . . .. . Very strange indeed and obviously I need to be certain that I am getting a 'like for like' replacement.

I am going to be phoning Mr Turner this afternoon to speak to their tech debarment but I though some of you guys might be able to shed light on this for me.

This thing is sitting on the floor next to the cylinder. It is a 2.5 bar pump that is boosting both the hot and cold supplies.

Thanks in advance!

 

[Gray0689]

Never seen one like that must be an old one indeed
But it's still a negative head pump and the one you will get will have one small exp on it too

 

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I think this is at least 15 years old!

It would last as long if it was not a Stuart Turner . . . .

I think it is the age that is putting me off - better to be safe than sorry like!!

 

[chris watkins]

If you can get the serial number of the pump body & quote it to Mr Turner he will tell you what the replacement is.
It is just an old twin with pressure switches on both H&C to switch it on & off, nothing to get worried about.
Why can't you re-build the old one ???

 

[Deleted member 25704]

As Chris says, its a twin pump with a negative pressure switch set.

Note: with normal shower pumps and the like, they have flow switches which activate the pump when water flows through the pipes (demand).

With a negative head the shower or tap outlet is above the level of the pump and hence flow switches are unsuitable.

The red expansion vessels are charged with air pressure and when the pump is running and comes to a stop, the pump builds up a pressure on the water side which buffers up the expansion vessel diaphragm. When a tap is opened, water is forced out of the tap by the pressure on the air side of the expansion vessel diaphragm and at the same time the switch is tripped for the pumps to meet the showering demand.

Its very possible that the vessels and switch gear are ok, and you just need the appropriate twin pump. I would think the price would double if you replace the whole lot. But we all know you can't win these days - if you just replace the pump, then the switch gear will probably fail in the process of doing it!

In my opinion, these are so 1980 in terms of their flow rate characteristics 50 litres a minute to some showers. It might be time to consider unvented and accumulator or alternative system.

 

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I have found out it is 25 years old!

My bad though - I am fitting a nice ST monsoon twin and it does have a little vessel on the top which I have not noticed before on other jobs . . . .

Thanks for the help boys!

 

[chris watkins]

Not a bad advert for Mr Turner's pumps, a. They may cost a bit more but 25 years use an't bad, hope the new ones last that long without the brooks crompton motors ?