Belated thanks for all your help with this. Work has now been done. New Grundfos UPS3 15-50/65 pump fitted and controller now correctly wired so water and heating can be programmed independently. He also changed the 3-port valve as it transpired that the person that wired the replacement controller incorrectly also fitted the wrong type of valve for the system. Boiler and system is now running the most efficiently it has for years. However there is now a noticeable hum resonating through the system that builds up shortly after it switches on. Strangely it seems louder in the downstairs cloakroom than it does in the airing cupboard itself. If you hold the pipes adjacent to the pump there is a slight vibration that seems to correspond with the frequency of the hum. Any helpful suggestions gratefully received. Thanks!
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- Thread starter Stephen JW
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The UPS 3 is a very powerful pump and if set very high can cause problems, can you take a photo of the settings, they will correspond to one of these settings.
It comes factory set to its max, constant curve iii
It comes factory set to its max, constant curve iii
Thanks John
It does seem to be set to the factory default. I have attached a couple of photos, one of the non-working original pump and one of the new UPS 3. The orientation of the UPS 3 is as seen (i.e. the photo is the correct way up).
As I said previously the system is running really well apart from the resonating noise. What setting would you suggest? The boiler is an old Potterton Netaheat Profile (annually serviced).
Many thanks again
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Hi Stephen,
Would suggest either PPII, which is nominally 3.8M but should run at around 2.5/2.6M at your demand OR CPI which runs at a constant 3M head.
CCIII meant you were more than likely running at a 6M head, no need, this is only used on pump installation and should be only run at this head for about 10 mins to assist in venting air.
You probably know how its done but press and hold the setting button for 3 secs to change pump modes, then briefly press to select the correct mode setting.
Would suggest either PPII, which is nominally 3.8M but should run at around 2.5/2.6M at your demand OR CPI which runs at a constant 3M head.
CCIII meant you were more than likely running at a 6M head, no need, this is only used on pump installation and should be only run at this head for about 10 mins to assist in venting air.
You probably know how its done but press and hold the setting button for 3 secs to change pump modes, then briefly press to select the correct mode setting.
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Thanks John. We tried that. In PPI, PPII, CPI & CPII setting the LEDs remained flashing and the pump didn't start running. We put it back into Constant Curve mode and selected CCII mode. It seemed to be struggling on CCI. Are we missing something obvious here? Many thanks again for your time and helpful advice John.
ALL the PP & CP modes operate with flashing LEDs (see below) so if lighting in any of the modes below as shown then the pump will/should be running. (but very quietly)
What do you mean by struggling?.
If CCI is too weak at 4.2M then not a hope of enough circulation on PPII or CPI.
If happy with CCII at 5.2M then leave it or perhaps try CPII at 4.5M which may give quiet running with enough head.
What do you mean by struggling?.
If CCI is too weak at 4.2M then not a hope of enough circulation on PPII or CPI.
If happy with CCII at 5.2M then leave it or perhaps try CPII at 4.5M which may give quiet running with enough head.
Thanks John. Ah OK didn't realise that the LEDs were supposed to flash. When I said struggling I just meant that the pump didn't start straight away, not sure what would have happened if I had given it time? On CCII one of the radiators didn't heat at all and another was lukewarm. Now the boiler has switched off and all the radiators are cooling down. No resonating noise at CCII but it's looking like the system only supplies all the radiators at CCIII which is somewhat concerning bearing in mind your previous remarks. Note that our system ran well for many years with our old Grundfos Selectric 15-50 pump until it failed recently. Would the type of 3-port valve fitted have any bearing on this? It's a Drayton. Apologies for my lack of knowledge regarding this stuff and thanks again for your advice. Stephen
What is the boiler power and is it a modulating boiler?
How many rads?.
IF the UPS3 is working properly then CCII is more powerful than CC3 was on your old 5M selectric.
The UPS3 on CCII will maintain +5M up to a demand of 1.1 m3/hr, 18.3LPM.
Also, there should be little or no delay in pump startup after changing settings.
Is the system clean as very dirty systems can build up magnetite on these pump rotors which can slow them down or stop them, the pump head can be removed for cleaning.
How many rads?.
IF the UPS3 is working properly then CCII is more powerful than CC3 was on your old 5M selectric.
The UPS3 on CCII will maintain +5M up to a demand of 1.1 m3/hr, 18.3LPM.
Also, there should be little or no delay in pump startup after changing settings.
Is the system clean as very dirty systems can build up magnetite on these pump rotors which can slow them down or stop them, the pump head can be removed for cleaning.
- May 23, 2015
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What was the old pump like eg in the outlets of the pump any blockage or was it clean and around 15mm dia ?
Hi John. Thanks for all the information you have provided. This is a steep learning curve for me as I am a complete layman and unfamiliar with the terminology and power ratings etc. But this is what I do know:
Boiler is Potterton Netaheat 50e which Google tells me is max. 14.65kw output
We have 10 radiators in all, smallest 72cm, largest 180cm
4 radiators + heated towel rail upstairs
3 long + 2 short radiators downstairs
The engineer drained, refilled and added inhibitor and fitted new valves with the new pump and 3-port valve.
When we put the pump back into CCIII after everything switched off on CCII last night the pump was ‘throbbing’ and making a ‘thrum-thrum-thrum’ sound as it was running. We left it for a few minutes to see if it would return to normal. It didn’t so we turned it off. This morning there was a lot of gurgling and ‘ticking’ but it is now running on CCIII as before. All radiators are hot. The resonating noise is back.
Many thanks again.
Stephen
Looks definitely like a pump problem there IMO, there were a few "dud" UPS3s sold, I would inform your engineer as a new pump should be supplied without question, under warranty, except that your system was/is filthy.
You can yourself just ensure that the pump isol valves are fully open and just recheck that the pump is orientated correctly, ie, if on the boiler flow side, pumping away from the boiler and if on the boiler return, pumping into it.
You can yourself just ensure that the pump isol valves are fully open and just recheck that the pump is orientated correctly, ie, if on the boiler flow side, pumping away from the boiler and if on the boiler return, pumping into it.
Thanks John. Sadly I don't know how to check these things. The pump itself is physically mounted upside down, presumably as if it were the 'correct' way up the mains cable and its mounting would prevent the airing cupboard door from closing. I have attached a few photos. A couple of further things to mention that may or may not be relevant.
1. Our system has no wall-mounted thermostat. We have old Servowarm thermostatic radiator valves on each rad.
2. We usually run the boiler on setting 3-4 on the control dial (range 1-5/max).
Thanks again!
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There is an arrow on the pump body, see if its pointing up or down, then follow the pipe (up or down) and see where its attached to the diverter valve and we can soon figure it out.
The pump valves, just turn each one clockwise until shut then anticlockwise until fully open, it should take ~ 3 to 5 full turns each way to fully close/open them.
The pump valves, just turn each one clockwise until shut then anticlockwise until fully open, it should take ~ 3 to 5 full turns each way to fully close/open them.
Thanks John. Valves seem to be fully open. Can't see an arrow on the pump body. Where should I be looking?
Does the setting on our boiler that I mentioned have any bearing (3-4 on range 1-5/max) on things?. Likewise the thermostatic radiator valves?
Settings on boiler and TRVs are fine.
The pump arrow is on the pump body directly behind o the plug socket and is pointing upwards, probably downwards in your installation (on right hand side).
Can you also get a close up photo of the arrowed area in attachment.
And also around the pipework runs from the mid position valve to the cylinder coil flow and return etc.
The pump arrow is on the pump body directly behind o the plug socket and is pointing upwards, probably downwards in your installation (on right hand side).
Can you also get a close up photo of the arrowed area in attachment.
And also around the pipework runs from the mid position valve to the cylinder coil flow and return etc.
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Arrow on pump was quite difficult to access and take snap of but have attached the best I could get. It is pointing down.
Also attached close up arrowed.
Many thanks
Attachments
So pump is correct, the arrowed item is a mini ball valve by pass which is partially opened, can't see any reason why CCII shouldn't give perfectly acceptable flow rates compared to CCIII, it should give ~ 90%. so still points to pump problems IMO.
Its a bit surprising that your engineer didn't try out any other modes as most would settle traditionally for CCII even if they knew nothing about the other modes.
Also point out to him that the UPS3 CCII is more powerful than the Selectric CCIII.
Did your engineer make any other changes apart from the new pump & mid position valve?.
So, Stephen, If it were my installation, I would contact him and inform him of results, can't offer any other words of wisdom I'm afraid.
Its a bit surprising that your engineer didn't try out any other modes as most would settle traditionally for CCII even if they knew nothing about the other modes.
Also point out to him that the UPS3 CCII is more powerful than the Selectric CCIII.
Did your engineer make any other changes apart from the new pump & mid position valve?.
So, Stephen, If it were my installation, I would contact him and inform him of results, can't offer any other words of wisdom I'm afraid.
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Hi John. Firstly thank you so much for all your words of wisdom. You really have gone above and beyond to help and it is very much appreciated. It makes a huge difference to us to be able to call the engineer back knowing what it is reasonable to expect from the UPS3 in general and particularly, as you say, that UPS3 CCII is more powerful than our old pump - which supplied the system perfectly well for many years.
We are not aware of any other changes he made apart from fitting the Grundfos pump (and new pump valves), Drayton mid position valve and rewiring the (previously incorrectly wired) existing Drayton controller. He also drained and refilled the system.
Can I just ask couple more things before signing off?
The engineer initially quoted for a Honeywell mid position valve but actually supplied a Drayton. We didn't query this as the controller is a Drayton. Is this likely to have any bearing on the issue?
I only noticed after our last exchange of messages that, after I tried different pump settings and returned it to CCIII, one radiator that had previously been hot was lukewarm and one had not come on at all (both downstairs). I turned the boiler controller to 5 and both radiators came on. Any implications there?
And finally a (probably) really stupid question... should the circulating pump be constantly running when only hot water is selected on the controller?
Once again, many thanks for all your help John, you have been brilliant!
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