Any ideas? Unreliable heating.

[John.g]

Where is the arrow?

On the pump body, will send photo.

 

[garyevans]

What do you mean by upside down? the pump label etc may be upside down but all that matters is that the arrow on the pump body is pointing in the correct direction.
Your picture is only darkness.

The picture of the old pump (blue) is rotated. The writing on it was upside down. It was the pump installed when the house was built.

 

[John.g]

Just to the left of the cable socket, on the pump body.

 

[garyevans]

Just to the left of the cable socket, on the pump body.

View attachment 79997

Yes, it is pointing downward

 

[John.g]

So, are you absolutely certain that the new pump is pumping in the same direction as the old one, ie, the arrow on the old pump was also pointing downwards??, Is you system as I showed above or can you post a photo of it?, its strange that you are getting problems at CP2 even though it is a bit high so CP1 may sort out the problem, was that system chemically cleaned or anything like that between pump changes?.

 

[garyevans]

So, are you absolutely certain that the new pump is pumping in the same direction as the old one, ie, the arrow on the old pump was also pointing downwards??, Is you system as I showed above or can you post a photo of it?, its strange that you are getting problems at CP2 even though it is a bit high so CP1 may sort out the problem, was that system chemically cleaned or anything like that between pump changes?.

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.

 

[John.g]

Well you will have to be happy (ensured) that the UPS3 is pumping in the correct direction before taking any drastic or unnecessary action, if the pipe coming out of the bottom of the pump then goes to either a three way valve or to a number of valves (all/any of which will have a motor with a cable) then pump direction is downwards, if these valve(s) come off the top pipe then the pump must pump upwards.

 

[garyevans]

Well you will have to be happy (ensured) that the UPS3 is pumping in the correct direction before taking any drastic or unnecessary action, if the pipe coming out of the bottom of the pump then goes to either a three way valve or to a number of valves (all/any of which will have a motor with a cable) then pump direction is downwards, if these valve(s) come off the top pipe then the pump must pump upwards.

Yes, that's where the 3 port valve is

 

[John.g]

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

 

[John.g]

Your old pump was probably a 6M Selectric (made in 2007) so the pump curves may look like this. If so then even speed 3 has a relatively low head of 2.5m at 0.7ms/hr and hopefully CP1 or PP3 will also not cause any pumpover problems.

 

[EvilDrPorkChop]

CP1 is equivalent to Speed 2 on the old pump, so CP1 will probably be about right.

 

[John.g]

View attachment 79949

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?.

 

[garyevans]

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.

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.

 

[garyevans]

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.

 

[garyevans]

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.

 

[garyevans]

Got closer. Yes arrow on right is downwards. View attachment 80051

All inlet valves downstairs are scorching hot. All rads have been bled. First 3 rads on system downstairs are warm but there 4 after that are not.

 

[John.g]

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.

 

[garyevans]

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?

 

[garyevans]

What does venting air mean?

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.

 

[John.g]

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.

 

[garyevans]

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.

 

[garyevans]

Cheers. In work now so will try again when I get home late afternoon.

That middle pipe seems to go into the bottom of the immersion heater.

 

[garyevans]

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?

 

[John.g]

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.

 

[garyevans]

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.