More powerful central heating pump than Grundfos UPS 15-60 (130) Super Selectric pump needed?

[stevet]

The central heating system in my largish house (20 radiators) uses a Grundfos UPS 15-60 (130) Super Selectric pump. After a while it started vibrating noisily and I had it replaced. The new one was beautifully quiet for about a year and then the same rattling noises returned, so I had it replaced again. That one did exactly the same; nice and quite for a year or so, but then started vibrating noisily through the house. I'm now onto my 4th Super Selectric pump (this one just 10 months old) and the noise is back.

My local central heating engineer reckons that the pump is not powerful enough for the system, so the bearings are wearing out quickly under the load and that I'll either have to keep replacing it or have the system modified to use a more powerful pump. Can anyone please advise:

a) Does his diagnosis sound right to you?

b) What pump would you recommend changing it to? Are there more powerful pumps that fit the same connections as a Grundfos Super Selectric, or is it going to involve draining down and widening the connections? There is only around 3" of clear pipe above the top connector and the nearest T-fitting, so there's limited space.

Many thanks.

 

[Dotty]

I know of someone selling a Grundfos UPS D65-120F commercial pump. It's worth £3, she wants 500 for it. She's in Crawley.

If you buy it I reckon she'll be very, very grateful to me..........

 

[IDCHAPPY]

Sounds like a bigger pump might help, how does the 15-60 run? Do all the radiators heat ok?

 

[Roger Welton]

What does the impeller and inside pump casing look like after failure? What size system is it running?

Regardless of what you replace it with it will have to be a Band A pump so another UPS15-60 is out.

 

[SimonG]

Dont fit an alpha.

I prefer to have a pump per zone, more expensive at install, but less wear and tear.

Have a look at an 8m grundfoss. Its about an inch longer than standard. But also look at the quality of your central heating water. Might be worth looking at a filter if you dont have one.

 

[Ray Stafford]

Usually when a pump is undersized, the symptom is poor system performance - slow to heat up, some rads/parts of the system only get lukewarm.

I havent heard of a Grunnie "working itself to death" like this.

Whilst I always hesitate to contradict the engineer on the spot - after all, he may have information that the OP didn't pass on - I would also be wanting to look at the quality of the system water or at other potential causes than just "pump fatigue".

 

[rpm]

Just being nosey here but what`s the average life span of one of these pumps guy`s or is variable and related to how many radiators etc. Be nice please.

 

[SimonG]

Just being nosey here but what`s the average life span of one of these pumps guy`s or is variable and related to how many radiators etc. Be nice please.

To be honest rpm how long is a piece of string.

Its like a lot of things these days, not built to last, no money in longevity

I know 2 houses next door to each other with exactly the same boiler at about 9 years old. Ones had a water pump and the others like triggers broom.

With water pumps though it could be influenced by many things, how dirty the water is, how its wired (ie is it over running against closed valves with no bypass because of the way it is wired, how long it runs each day, how close it is to the boiler, how its positioned (ie is it running partly dry). These are jyst off the top of my head.

 

[Lincsplumber]

Hello Stevet,
Whats the position of the pump, is it on a vertical pipe or horizontal pipe? is the pump housing upright or tilting to left or right? What type of system is it connected to....sealed/ open vented? There's quite a few factors that could contribute to a noisy pump.

 

[Ermintrude]

Is the pump just on 24:7?

 

[kris]

Rays bang on there has to be another factor causing the shortened life span of the pumps. I.e dirty
Sludgey water . Common on bigger sized properties .

 

[AWheating]

prob fitted in the wrong plane or poor water quality really, if the pump was undersized it would struggle to work from the get go. Atleast iliminate these questions first.

post pictures of the pump fitted and if possible the inside of it once removed.

 

[chris watkins]

Is there a by-pass installed ????