Ultracom 30CXi - replace pump head or complete pump??

[Rog200455]

Came home last night to find system off and pressure down to 0.3 bar (0.1 bar this morning). There is a drip from the pump and the pump had been noisy for some time. I note from the manual that it is possible to replace just the pump head or the complete pump. How do you tell which is the correct action to take please?

 

[ianmcd]

unlikely to be the pump body and you could just replace the head but its £264 retail for the head it does come with a new washer . it looks like a Wilo pump head so have a look at your one it should have numbers on it think the Wilo begin with CP then a number if it is just go to B&Q and get the same number complete pump and split it and use the head probably about £50 for the complete pump but the whole pump wont fit your boiler the body is different, when you have the pump head off give the body a good clean

 

[Agile]

Your pump will be noisy because dirt has worn out the pump bearings.

While changing the pump you drain out the system and refill with fresh water and ideally add a cleanser like X800 or have it power flushed.

Tony

 

[Rog200455]

unlikely to be the pump body and you could just replace the head but its £264 retail for the head it does come with a new washer . it looks like a Wilo pump head so have a look at your one it should have numbers on it think the Wilo begin with CP then a number if it is just go to B&Q and get the same number complete pump and split it and use the head probably about £50 for the complete pump but the whole pump wont fit your boiler the body is different, when you have the pump head off give the body a good clean

Thanks. I have now removed the head and can see that there would be no need to replace the whole pump. When I turn the impeller it is really rough, so that accounts for the noise.

I can't see any CP numbers on the pump but here is some of the identification: CDH Class F - TF95. 4514471. VHSL15/6 HE-2. 0020005804. I think the last number is the Glow Worm part number.

Do you think that this one will be available cheap at B&Q or anywhere else?

 

[Rog200455]

Well, I have learnt a lot in the last week! First of all thanks to ianmcd for the advice - it kept us warm! There were 2 Wilo pumps at B&Q: One B rated, about 50W and an A rated smart pump 15 - 45 W. The B rated pump head was the same physical size as my old pump, so I bought that one - mistake, when I split it, it was obvious that the design was completely different. Took it back and exchanged for the smart pump, which had a smaller outer diameter, however the fixing hole centres were the same. Split it and noticed that it had a smaller impeller, however I was able to fit it to the old pump body. It worked but not 100% correctly. The boiler was not able to modulate correctly and could not cope with the times of the day when we have only 4 rads on. So, instead of settling down to a steady output, it was hunting around the set-point, overshooting and shutting down, then firing again after the pump time-out period. The house was still warm but I presume at a cost, due to the boiler not operating in the most efficient way. Whilst taking a shower, the temperature would fluctuate. Managed to get hold of a second-hand original pump head off e-bay for £30. Just fitted and it's working fine. The official new replacement is a Grudfoss but you have to change the complete pump, as the head will not fit the old body - £119 + VAT from my local stockist but there were none in stock.