Old Glow-Worm 45-60B

[Agile]

You say you don't want to save money but you don't want to do something that is free!

Remove the pump head, see if its blocked in the impeller and do the finger test as explained in the FAQ!

Tony

 

[robertbullen]

Pump for £45: http://www.screwfix.com/p/wilo-smart-pump-domestic-circulating-pump/33590 if needed. I'd expect the pump to take more than you describe to stop if it was healthy, and also, just because the shaft is rotating, doesnt mean the pump is actually moving any water!

Sludge may not be helping matters, if HW is gravity circulation then there may be a partial blockage in the primaries slowing things down. Are you getting plenty of hot water? To clean, have a look at Sentinel, either X400 which can be left in a for a few weeks without issue, or the X800 which you'd need to be more careful with.... http://www.sentinel-solutions.net/product/listing/central-heating/liquids/[/QUOTE]

Would this pump you've suggested be a suitable replacement for my current one...

 

[Agile]

You say you don't want to save money but you don't want to do something that is free!

Remove the pump head, see if its blocked in the impeller and do the finger test as explained in the FAQ!

Tony

Better to do what I have suggested first.

I would not recommend a used pump unless it was known to be 100% working and not just said to be by an ebay fraudster!

 

[robertbullen]

I intend to remove the cover but I thought having a new pump ready to go would be a good idea in case the old one is knackered.

 

[Agile]

Its only a five minute job to put the pump head back.

Most people live within a 30 min drive of a Screwfix or Toolsatation who sell cheaper pumps!

 

[robertbullen]

I would rather have a new pump ready to go, I can take it back should I not need it.

I saw one comment about damaging the seals on an older pump.

 

[Hugh Jaleak]

It will fit, most pumps are standard size now. Some older types may need pipework altering, but yours should be a straight swap. Probably wise to change pump valves at same time, don't rely on the existing valves to shut off to change the pump, to avoid a potential mess I'd drain system.

 

[robertbullen]

Great, cheers. And do you reckon the pump is powerful enough for my 8 rads?

Thanks again.

 

[Hugh Jaleak]

Will be ample for your requirements.

 

[robertbullen]

Well, I've removed and flushed every single rad until the sludge was out and clean water flowed. I've changed the pump, still the same problem. The old pump was in a mess and the pump valves coated inside with iron flakes. I've now put the x400 in the system and refilled it. Waiting to see what happens over the next week or 2.

I'll keep you posted.

Thanks again for you advice.

 

[robertbullen]

Hi,

When running mains pressure water through the pipework in such a way that there was only one route for it to take, through the boiler, there seemed to be no problem in that water getting through. I presume from this that there is no major restriction as the water passed through the boiler and related pipework.

If I only leave 4 out of 8 rads on, they get very hot, when I turn them all on, they get warm at best. I've balanced the rads best I can.

The boiler is still firing for a couple of minutes before cutting off for a couple of minutes. The pump keeps running throughout. One more thing I can think of is the thermocouple between the "chassis" up near the top of the heat exchanger and the thermostat control on the boiler.

I would have thought a faulty thermocouple would have resulted in the heat not being correctly relayed to the thermostat and thus the boiler overheating, but could the opposite happen?

Just to be clear, this is not the thermocouple between the pilot and the safety cut-out.

Thanks in advance.

 

[twgas]

Your boiler is, as you've already been told, working ok. Your problem is circulation, did you get a new or used pump?
If the old pump was really bad there might be a restriction in the pipework.

 

[robertbullen]

Yes, I've replaced the pump and flushed the system, one rad at at time off the wall and again connected. I used the Sentinel x400 for 2 weeks before the flush using mains.

 

[twgas]

I understood you rreplaced the pump, but did you buy a NEW or USED one (I wouldnt be trusting a second hand pump)

 

[robertbullen]

Sorry, brand new from Screwfix.