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so 3 port below pump and pump pumping downwards is correct, CP1 or just maybe PP2 next step??

WhT was happening when the pump was stopping as can't see it
The pump was making a very strange noise. The file I added was a video file.
Starting from scratch tonight. Photo of setup attached showing port valve etc. Going to try CP1 following the details posted on Sunday, starting with HW ON ETC.
PXL_20221213_184006839.jpg

Gary, getting a bit confused myself re arrow on pump, can you just confirm that (if) the pump is now pumping downwards then the engineer will then have turned the head through 180 deg and the arrow will be on the right hand side of the pump body, pointing downwards.

Assuming it was how is your system performing now?.
The arrow is downwards on the left side behind the cable socket. I can't see anything on the right hand side. Best photo I can take given the angle is here.
PXL_20221213_215740774.jpg
 
Not getting anywhere really. I had to leave heating on today as someone was home so it was on CP1 with all upstairs rads off so the living room rads were warm. The kitchen rads beyond those never really warmed up properly. Have tried to restart CP1 following the process I was asked to go through on Sunday evening but when I switch upstairs rads off there heat is not too hot downstairs with the last 2 or 3 on system almost getting nothing. Like i say I am not a plumber so have no knowledge at all but I know when it won't work just by noise of pump. When it is almost silent I know it will work but when it makes more noise it won't. I think I need to have the system cold to be able to try a proper CP1 or PP1 reset.
 
Not getting anywhere really. I had to leave heating on today as someone was home so it was on CP1 with all upstairs rads off so the living room rads were warm. The kitchen rads beyond those never really warmed up properly. Have tried to restart CP1 following the process I was asked to go through on Sunday evening but when I switch upstairs rads off there heat is not too hot downstairs with the last 2 or 3 on system almost getting nothing. Like i say I am not a plumber so have no knowledge at all but I know when it won't work just by noise of pump. When it is almost silent I know it will work but when it makes more noise it won't. I think I need to have the system cold to be able to try a proper CP1 or PP1 reset.
Got closer. Yes arrow on right is downwards.
PXL_20221213_220628339.jpg
 
Very strange allright, presume not something daft like the pump valves not opened fully, they look like gate valves so should be ~ 3 or 4 full turns from fully shut to fully open. There arn't too many things left, the pump was probably changed out without drain or partial system drain down, possible sludge build up but unlikely except the F&E tank was full of crap and drained down into the system. (if system drained)

The possibility of a faulty UPS3 still exists but if so unlikely that air would continue to build up, are you still venting air, you say all rads have been bled?.

CP1 at 3M should not cause any problems and is required for most systems of your size, my system runs at 3.5/3.6M with the (Wilo) pump set to a PP setting of 4.6M.
 
Very strange allright, presume not something daft like the pump valves not opened fully, they look like gate valves so should be ~ 3 or 4 full turns from fully shut to fully open. There arn't too many things left, the pump was probably changed out without drain or partial system drain down, possible sludge build up but unlikely except the F&E tank was full of crap and drained down into the system. (if system drained)

The possibility of a faulty UPS3 still exists but if so unlikely that air would continue to build up, are you still venting air, you say all rads have been bled?.

CP1 at 3M should not cause any problems and is required for most systems of your size, my system runs at 3.5/3.6M with the (Wilo) pump set to a PP setting of 4.6M.
What does venting air mean?
 
What does venting air mean?
Opening the vent screws and getting rid of any air in the rads. (Bleeding the rads)
John, should the gate valve directly under the pump be fully open? The middle of the three you can see in the photo I uploaded yesterday.
Not sure about the one with the red handwheel (you would have to trace it but let it be just now whatever its opening is).

The two brass valves, immediately above and below the pump MUST be fully open, get a adjustable spanner or even a pliers and try shutting first, if they are open then you should get 3 to 4 turns to shut, then immediately reopen, ie they must be ~ 3 to 4 full turns open from fully shut.
 
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Opening the vent screws and getting rid of any air in the rads. (Bleeding the rads)

Not sure about the one with the red handwheel (you would have to trace it but let it be just now whatever its opening is).

The two brass valves, immediately above and below the pump MUST be fully open, get a adjustable spanner or even a pliers and try shutting first, if they are open then you should get 3 to 4 turns to shut, then immediately reopen, ie they must be ~ 3 to 4 full turns open from fully shut.
Cheers. In work now so will try again when I get home late afternoon.
 
Opening the vent screws and getting rid of any air in the rads. (Bleeding the rads)

Not sure about the one with the red handwheel (you would have to trace it but let it be just now whatever its opening is).

The two brass valves, immediately above and below the pump MUST be fully open, get a adjustable spanner or even a pliers and try shutting first, if they are open then you should get 3 to 4 turns to shut, then immediately reopen, ie they must be ~ 3 to 4 full turns open from fully shut.
Yes, all rads are bled - doing it all the time. No air in them.
The way I got the CP2 to work on Sunday (bleed rads, turn on HW, run HW, turn off HW, turn on CH, when upstairs rads get hot, switch them off and pump heat downstairs) is failing on the last part with CP1 as only 3 or 4 of the 7 rads downstairs get the heat - should I switch all off apart from last one and rebalance the rads?
 
When you bled the rads on Sunday, how much water did you bleed off each?

If no air in them then pointless venting, except that you are getting some heat in them by actually bleeding off a few litres of water which means no circulation or circ pump defective, CP2 at 4.5M even with all rads open (no balancing) should circulate plenty of water to get all/most quite hot, you have another problem IMO.
When you come home and if you find that the pump valves are fully open (and probably are) then may have to check the circ pump.


That middle pipe seems to go into the bottom of the immersion heater.
probably the cold water supply to your HW cylinder.
 
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If no air in them then pointless venting, except that you are getting some heat in them by actually bleeding off a few litres of water which means no circulation or circ pump defective, CP2 at 4.5M even with all rads open (no balancing) should circulate plenty of water to get all/most quite hot, you have another problem IMO.
When you come home and if you find that the pump valves are fully open (and probably are) then may have to check the circ pump.



probably the cold water supply to your HW cylinder.
Thanks John. I have bled the rads but not emptied them per se - when you say 'no circulation or corc pump defective' what else could cause the 'no circulation'? The weird thing is that on Sunday after I changed to CP2 all rads were hot, same Monday but then Monday night the downstairs rads went cold. So that must be an airlock? But there is no air in rads! Given that we have had heat i would guess the pump valves are fully open.
 
Thanks John. I have bled the rads but not emptied them per se - when you say 'no circulation or corc pump defective' what else could cause the 'no circulation'? The weird thing is that on Sunday after I changed to CP2 all rads were hot, same Monday but then Monday night the downstairs rads went cold. So that must be an airlock? But there is no air in rads! Given that we have had heat i would guess the pump valves are fully open.
last one - the screw in the pump to deblock - manual says to turn screwdriver anticlockwise, but youtube vids say ant and then clockwise? Is that a possible issue?
 
That makes sense, an airlock is a distinct possibility, the only way ("new fresh") air can get into the system is through the air vent, the pipe that bends over the F&E (small) tank. Try and tape a container of water (say a few litres) under this vent with the open end immersed in the water and watch it while starting/running the pump or as I suggested earlier on, just get someone to do as I suggested in post #15, do this first mybe.
 
Turn all the rads off downstairs bar one, get that one red hot. Turn it off. Turn next one on and repeat for rest. It's just airlocking that's all by the sounds of it. If valves are red hot to radiators, then sounds like air. You've not balanced up downstairs have you?
 
Turn all the rads off downstairs bar one, get that one red hot. Turn it off. Turn next one on and repeat for rest. It's just airlocking that's all by the sounds of it. If valves are red hot to radiators, then sounds like air. You've not balanced up downstairs have you?
Yes, balanced all rads up and down a few times.

Had a plumber come round. He has checked the pump, the valves, drained the system, rebled the system, checked the feeder tank in loft and it is still the same. He is convinced there is a blockage in the 'return' feed pipe (I am not going to pretend I know what that is) and we need to do a powerflush.
 
I don't see why anyone would drain down a system just to change out a pump, however we can talk till the cows come home but
I would go way and buy one of those cheap plug in energy monitors on amazon or where ever, remove the pump cable from the terminal box, Connect a 3 pin trailing socket into the terminal box where the pump was, put a 3 pin plug on the end of the pump cable, plug the energy monitor into the socket and plug the pump into the energy monitor and monitor the pump power, that will eliminate or not a pump problem to start with as these pumps have a very high failure rate or inconsistent performance even out of the box, the monitor is only £15 or £20 and very accurate.
 
Yes, balanced all rads up and down a few times.

Had a plumber come round. He has checked the pump, the valves, drained the system, rebled the system, checked the feeder tank in loft and it is still the same. He is convinced there is a blockage in the 'return' feed pipe (I am not going to pretend I know what that is) and we need to do a powerflush.
Unbalance the downstairs ones, so they're open fully. Leave upstairs balanced.
 
I don't see why anyone would drain down a system just to change out a pump, however we can talk till the cows come home but
I would go way and buy one of those cheap plug in energy monitors on amazon or where ever, remove the pump cable from the terminal box, Connect a 3 pin trailing socket into the terminal box where the pump was, put a 3 pin plug on the end of the pump cable, plug the energy monitor into the socket and plug the pump into the energy monitor and monitor the pump power, that will eliminate or not a pump problem to start with as these pumps have a very high failure rate or inconsistent performance even out of the box, the monitor is only £15 or £20.
The plumber took the pump off and checked it and said it is fine. The pipe that feeds downstairs is overhot as is the feed to boiler so the boiler is cutting out intermittently thinking it is overheating.
I'm guessing everything worked before new Pump OK?
No it was hit and miss since the heating went on at start of November. BG decided it was the pump but looking back I reckon there was a blackage then too.
 
HW & CH worked a treat for 2 weeks after renewing pump?,
Have you checked the F&E tank as suggested or at least look into its condition?
Is there a magnetic filter, usually installed on the boiler return and just before the boiler?
 
HW & CH worked a treat for 2 weeks after renewing pump?,
Have you checked the F&E tank as suggested or at least look into its condition?
Is there a magnetic filter, usually installed on the boiler return and just before the boiler?
HW & CH worked fine once I balanced the system after new pump installed. PLumber checked the F&E tank yesterday and said there was no issue. No filter on the boiler return.
 
Maybe I'm overthinking it but if a system works fine for a few weeks and then stops working then the easiest common denominator to check out is the pump, your plumber obviously checked the pump ports, impeller, etc for sludge but he couldnt check it electrically/output etc but you can do that yourself by spending a few quid, that monitor can also be useful for balancing the system.
 
Maybe I'm overthinking it but if a system works fine for a few weeks and then stops working then the easiest common denominator to check out is the pump, your plumber obviously checked the pump ports, impeller, etc for sludge but he couldnt check it electrically/output etc but you can do that yourself by spending a few quid, that monitor can also be useful for balancing the system.
If you could send me a link to one I will take a look - does it plug into the cable socket on the actual pump?
For info, I have just been into attic to look at F&E tank - no spurt of anything anywhere when the pump stopped. I am home alone so can't look now at what happens when the boiler comes on.
 
Something like this, I wouldn't spend more than £15 or £20, all you want to monitor is the pump power in watts, nothing fancy required.

1671099957102.png



Don't know where you live but you can get one of these in Maplins? or the like, or Amazon.
For initial pump test, (boiler off) just note and remove the terminal numbers where the pump cable is connected, then remove it and fit a 3 pin plug to this cable, then plug the energy monitor into a extension lead powerd from anywhere and plug the pump lead (with now 3 pin plug) into the power meter and you can carry out cold pump tests with boiler switched as the 3 way valve will allways be open to either the CH or the HW. Depending on results, to do a longer/hot test, get a 3 pin socket and connect it with a bit of cable, connect the other end into the terminals where you removed the pump cable, then connect energy monitor and pump cable as above and fire up your boiler, you can then monitor the power indefinitely.
 
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View attachment 79999
This is the old pump and if it appears you will see what I mean by upside down. I don't have any other image so can only presume the British gas engineer who put the new one in ensured it is pumping on same direction. No chemical cleaning I am aware of.
Can't see the arrow, but by the shape of the casting of the cast iron section, this certainly looks to be pumping downwards.
 
Something like this, I wouldn't spend more than £15 or £20, all you want to monitor is the pump power in watts, nothing fancy required.

View attachment 80077


Don't know where you live but you can get one of these in Maplins? or the like, or Amazon.
For initial pump test, (boiler off) just note and remove the terminal numbers where the pump cable is connected, then remove it and fit a 3 pin plug to this cable, then plug the energy monitor into a extension lead powerd from anywhere and plug the pump lead (with now 3 pin plug) into the power meter and you can carry out cold pump tests with boiler switched as the 3 way valve will allways be open to either the CH or the HW. Depending on results, to do a longer/hot test, get a 3 pin socket and connect it with a bit of cable, connect the other end into the terminals where you removed the pump cable, then connect energy monitor and pump cable as above and fire up your boiler, you can then monitor the power indefinite
Hi John, apologies but that is like reading Greek to me! No idea which cable you are referring to. I wlll attach a picture of the setup - electrically, everything seems fine.
 
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Can you see where the end of the pump cable is connected?, it is electrically connected correctly but want to monitor the pump power which will show if the pump is performing electronically correctly by removing this cable and putting a 3 pin plug on the end to enable it to be plugged into the power meter.
 

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