Replacement pump for Grundfos Selectric 4

[Circuital]

Hello all,

I may have to get my central heating pump changed as it is making an almighty rattle all the time* but I am not sure which one to get. The pump I have currently got is labelled 'Grundfos Selectric 4', Type 4 -50/130 (please see pictures attached) and has 4 speed settings. Is there an equivalent Grundfos pump please? Also, is it worth considering other brands as there seem to be a few cheaper ones available online?

Thanks in anticipation,

Suresh

*I have already bled the system of air. I had a problem with a few rads not working but draining the system and then cleaning it with Sentinel X400 seems to have fixed this but the loud pump rattle remains. My plan is to drain and flush the system again in a few days, then change the pump, before adding inhibitor and refilling it again.

 

[muggles]

The DAB Evosta will be a good replacement - this is the pump I keep in stock on the van and the ones I've fitted so far have all proved to be reliable. It will also draw about a third of the electrical power of your existing pump, so should pay for itself

Be aware that those old pump valves will leak if you try to use them. No ifs, no buts, they will leak. You'll need to drain your system to replace them as well as the pump. I've started using butterfly handle valves with good success although I can't comment on their longevity yet!

 

[Circuital]

Thanks for the quick reply; i'd already looked at those DAB ones and now i'm more re-assured about buying one. I noticed the link you provided says "Install with motor shaft horizontal". Apologies for the silly question but isn't my Grundfos one currently installed vertically?

Also just out of interest, what do the numbers mean on the pump please? The Dab one describes itself as 40-70/130, where as the original Grundfos has 50/130 written on it?

Also, my plan is to drain the system anyway, then unscrew the unions and then fit the pump, if I don't actually turn the screw on those valves, will they still leak? Obviously i'm trying to save a couple of quid here but i'll default to your judgement.

Thanks again

 

[Gasguru]

Just install the new pump the same as the old pump....behind the large screw on the Grundfos is the pump shaft which must be installed horizontal to prevent excessive wear etc.
The Grundfos numbers mean it's a 5m head ie. it can support a column of water 5m high (with no flow...a pump is never run like that though), the 130 refers to 130mm distance between valves (standard nowadays).
The Dab means it can provide a 4 to 7m head.
If you don't touch the valves you might be lucky but I would replace them with pump gate valves.
Clean out the debris in F&E cistern before you drain down...got a wet vac?

 

[Circuital]

Thank you for the detailed response, it make much more sense now! I've already cleaned out the F&E tank and am currently circulating Sentinel X400 cleaner around the system, which has sorted the issues with the cold rads (it's an annoying microbore system which I think had got clogged up). After circulating the cleaner for another couple of days, i'll isolate the F&E tank again, clean out any more debris and then drain the whole system again.

At the risk of seeming cheap, any thoughts on me getting this Jassferry one instead? My eventual plan in a couple of years to get an extension on the house and at the same time, upgrade to a combi boiler. From the reviews i've read of the Jassferry ones, they seem to do the trick but there don't appear to be any long-term reviews.

 

[Gasguru]

Those pumps are illegal to fit (AFAIR the building regs outlawing them came in around 2015). The ebayer is lying as those pumps are old school and considered standard efficiency. It's up to you, the pump police won't hunt you down.

Most of us in the trade think the move to genuine high efficiency pumps is pretty pointless for the average household but the EU look at Europe as a whole and cream themselves at the potential CO2 saved...especially the Germans with their ridiculous systems that run the pumps 24/7.

A genuine high efficiency pump might save you £5 to £10 a year at best but given their often shorter lives there's little benefit. True eco-warriers stick on another jumper and make considerable savings.

 

[Circuital]

Just a quick message to say that I fitted the Jass Ferry pump after all and it's still going strong nearly 3 years later. Thought this might be useful for anyone thinking of buying one.