Should I buy a new pump?

[redconker]

I have two Grundfos UPS 15 -60 pumps on my central heating system. A heating engineer has recommended I remove 1 as my system is "overpumped" and also suggests that I replace the remaining pumps as it's of uncertain age.

My system is overflowing into the header tank therefore the water is being oxygenated. The engineer feels this would have corroded the propellers.

I'm new to the house but the pumps doen't look that old - are these reliable long term or am I storing up an issue for later?

Thanks.

 

[D_Hailsham]

I have two Grundfos UPS 15 -60 pumps on my central heating system.

Do you have a hot water cylinder?

If so, is one pump in the radiator circuit and the other in the cylinder circuit?

A heating engineer has recommended I remove 1 as my system is "overpumped" and also suggests that I replace the remaining pumps as it's of uncertain age.

Grundfos pumps are very reliable and don't usually need to be replaced until they have broken down.

My system is overflowing into the header tank therefore the water is being oxygenated. The engineer feels this would have corroded the propellers.

If the impellers had corroded, the pumps would not pump so well, so there would be less chance of pumping over. In any case the impeller is made of a composite material, not metal, so corrosion is very unlikely due to oxygenation; although sludge could cause problems.

Is the pumping over a new problem? If so, have you made any recent changes to the system?

If not a new problem, how long has it been going on?

Do all the radiators heat up properly?

Are any radiators hot at the top and cold at the bottom?

 

[redconker]

thanks for the response.

Is the pumping over a new problem? If so, have you made any recent changes to the system?

I've only lived in the house a short while so I'm not sure. No changes have been made to the system

If not a new problem, how long has it been going on?

Sorry unclear. If I turn the boiler heat down, it doesn't happen so much

Do all the radiators heat up properly?

Some get hot at the top but not at the bottom

Are any radiators hot at the top and cold at the bottom?

Yes - as above.[/quote]

 

[Ronald0]

Are the pumps on min. speed?

 

[D_Hailsham]

I've only lived in the house a short while so I'm not sure. No changes have been made to the system

If I turn the boiler heat down, it doesn't happen so much

Some get hot at the top but not at the bottom

Sounds as if you inherited the problem when you moved in.

A rad which is cold at the bottom and hot at the top is a sign of sludge.

You may need a powerflush but, before spending a lot of money, you could try using a cleaner such as Sentinel X400. It needs to be left in the system for about four weeks to do any good. You could also remove the dodgy radiators and flush them through with a hose in both directions. Thumping a rad with a rubber hammer can help dislodge the sludge.

You have not answered my question about the Hot water cylinder or which circuit the two pumps are in.

 

[redconker]

Sorry - regarding the pumps - I have one for the hot water and another for the central heating (presently). The engineer says this is not necessary - 1 will do?

He has also said this is an unusual setup as most homes only have 1 pump. As I've said before he blames the overflow on the system being overpumped.

The pumps are set at 2 (from 3) for central heating and 3 (from 3) for hotwater.

Thank you very much for your help.

 

[oilman]

The engineer says ............

He is a plumber with delusions, don't be fooled. If you have two pumps, stick with two pumps, it hardly matters, except that it may be too complex to get his head around.

 

[Agile]

There is nothing wrong with two pumps and Grunfos marketed a setup with two pumps.

For a start, turn the hot water pump down to "1".

It seems as if your plumber is short of work and wants you to pay him a lot to do changes which will not give you any benefit.

Certainly the pumping over is a serious condition and should be sorted within the next very few days.

Search this site and see the sorry tale of someone who ignored my advice and lost about five radiators to leaks because he would not treat my advice as urgent.

Tony

 

[twgas]

two pumps are ok providing they are correctly positioned in the system, if yours is pumping over it may mean apoorly designed/installed system.