Water pumbs

[Nigel]

Hi,

I have a water pump between my hot water tank and the boiler ( no element just feed from the boiler) and then one after the hot water tank and the pipes. My question is they have 3 speed settings on them which is the best position?? Does it affect the hot water pressure?? If not what do they do??

thank-you.

Nigel

[mike]

"Nigel" wrote in news:455050ed$1 [e-mail]:

I think ythe first one circulates hot foul water from the boiler through a pipe in the hot water tank to jeat the hot clean water you use. The speed to set it is as low as you can for it to work properly; too fast and it is noisy, too slow, and the boiler gets too hot and it's thermostat will keep cutting out (short cycling).

All that applies to the relatively simple systems I'm used to - be prepared for different responses for other types of H/W system.

The second... is it a Grundfos UPA 15-90? If so, it is to improve your hot water pressure and flow, and the settings are not speeds, but off, on and auto (the normal setting). In this position a flow switch wil cause the pump to cut in when a tap is turned on and assist the flow.

HTH

mike

[Nigel]

Hi Mike,

thanks for the info- I think the first one does what you said that is set at speed 2.

The other one is definitely a pump it is the same as the other 3. ( we live in Austria so the system is strange!!- like no inhibitor in the radiators!!!).

I just wonder what speed the second pump should be and what it actually does. Does it send the water around to the taps?? So does a high speed help or it is just pressure that feeds them.

thanks

Nigel

[mike]

"Nigel" wrote in news:45509a67$1 [e-mail]:

I dunno; the Grundfos booster looks just like a normal circulating pump - that's why I quoted it's part number; if your second pump is a normal pump it will be running all the time - not good if it's working into closed taps, or will somehow be controlled, or even switched off at source and just getting in the way.

It could be controlled by a separate flow switch if it's being used as a booster.

But I believe (heads down, possibly incoming fire) the materials are different, as a circulating pump works in oxygen poor recirculating fluid, and a booster pump is in normal water, so a circulating pump might die quickly in fresh water.

Anyhow, that's all my knowledge on the subject (didn't take long, did it?), so I hope there's something in there that will help

mike

[Sparks]

You might have some kind of hot water ring-main installed.

When you turn your hot tap on, furthest away from your hot water cylinder, how long does it take to run hot? or approximately how much cold water comes out before it get's hot?

Sparks...