Third central heating pump in 5 years!

[doitall]

As above which you keep ignoring.

The attitude of the pump is why they fail.

Not running the pump in test mode through the Summer is another reason they seize up.

 

[seco services]

Why else would pumps fail if the water is clean, no debris etc

The way it's angled can knock the bearing out.

 

[Glenbirnie]

I dont understand the term attitude? Is this the same as orientation? Ive never heard attitude used in this context before.

So whats your thoughs about having the Grundfos on its back?

Is there a best practice which way it should be oriented?

Thanks

 

[doitall]

The attitude in the angle it's at, the shaft should be horizontal/level in all cases.

Ideally the pump should be Horizontal or pumping up, as well.

 

[Dan Robinson]

Flipping heck.


The "attitude of the pump"

The "attitude of the sun".

Same meaning.

What orientation is it.

Post a picture.


There are pictures of correct or incorrect "attitudes" in the pump manual. It is the same for any pump IIRC.

 

[Dan Robinson]

the pump used to sit on its back, the big silver screw and Grundfos face palte with all the spec facing the sky.

That is wrong and will not do the pump any favours.

 

[ALEC1]

pump shafts should always be horizontal or near horizontal ensuring the screw is slightly facing down. This is to avoid the pump running dry which causes pump failure...

another thing to avoid is pump down with low inlet pressure...ie an OV system with the header tank less than 3m higher...

 

[DeltaT2]

There is no point me posting a pic as the pump which as just failed has only been on the new system since November.

I therefore put its failure down to something from the last system.

I know they had severe problems from day one with the Rayburn, heat exchanger was replaced, fan replaced, main circuit board melted and replaced etc a long list of problems and complaints. I couldnt put into words how bad the service from Rayburn/AGA had and has been on a cooker/boiler that cost the previous owner nearly £10k! They are a disgusting company and their products are poor.

Believe me you're not the only person that has had a lot of problems with Rayburn appliances, we had a nightmare with one about 15 years ago & I swore blind then we'd never fit another one. I know of many that have been a complete disaster, AGA/Rayburn have a lot to answer for. These poor people have paid a fortune!!!

 

[DeltaT2]

I dont understand the term attitude? Is this the same as orientation? Ive never heard attitude used in this context before.

So whats your thoughs about having the Grundfos on its back?

Is there a best practice which way it should be oriented?

Thanks

Have you tried 'cleaning the can' on the faulty 15-50?? Though chances are it's f.cked(technical term) if it was on it's back. Deffo a case of bad 'attitude'...............

 

[Boilerman2]

Grundfos pumps are NOT supposed to be installed with the rotor vertical, it causes air to trap which will wear out the pump fairly rapidly, if the pump was in this orientation previously then this could be the problem the shaft should be a few degrees above horizontal for optimum performance

 

[Glenbirnie]

Pic attached, the pump body is tilted slightly upwards. This is the old pump but in the new location.

Untitled

• Glenbirnie
• 2 Mar 2012
• 1

 

[Dan Robinson]

You should rotate the head 90 degrees and bring the shaft further to the horizontal.

 

[Glenbirnie]

Excuse my ignorance I dont know what these pumps look like internally. Are you saying the threaded connections and gate valves are ok?

I just need to slacken them and rotate the whole pump so the silver screw comes down slightly until it is horizontal?

 

[D_Hailsham]

the pump used to sit on its back, the big silver screw and Grundfos face plate with all the spec facing the sky.

That's wrong for a start. Why "used to"?

From Grundfos leaflet:

Where pumps can only be installed in horizontal pipework, it is imperative that the pump shaft is horizontal, or slightly higher at the vent plug end.
The shaft must not fall below the horizontal plane, even by a few degrees, as this causes premature wear of the top bearing and shaft.
Pumps should not be installed with the shaft in a vertical plane, as this may lead to dry running of the top bearing, noise and possible pump failure.

 

[Glenbirnie]

Mr Hailsham. Used to because this pump was used in another part of the house. The boiler was replaced and moved (used ot have a Rayburn range) Ive only been in the house 10 months. When the new boiler went in the pump was put next to the hot water tank, it used to be inaccesible under the gound floor.

From your Grundfos extract the new instalation ie the pic Ive attached is correct. The silver vent screw is facing upwards slightly.

Do you agree?