Hi all just picking your brains 2 pumps with flow rates of 3.8 and 5.7 which is the more powerful, also can you fit a commercial pump into a domestic system?
Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
You are pumping practically NIL as you can see from the pump curve that the flowrate at 5.9M is 0.
The pump power is 22/23kw, you should see this displayed and also the flowrate showing 0 M3/hr, so you might note these.
Also just shut the pump outlet valve for 10 secs or so with it running and the above numbers 5.9M/22kw/0.0M3/hr should remain the same.
Hi well interesting results:- I turned off the rad in the sitting room (which is 2400mm x 600mm double panel) and left the kitchen one open and left the entrance rad open, the entrance rad started to get hot, the kitchen started to get hotter than before so turned that one off and the entrance rad got hotter, which means to me there is no airlocks, here's some info on the pipe work the entrance is on 10mm pipework the kitchen is on 8mm pipe work, the sitting room is on 15mm pipe work. Being a disabled pensioner (72) I am at my time of life not able to rip out the dead legs and increase the size of the pipe work, I could shut off the kitchen rad as the kitchen is open to the sitting room so the sitting room rad would warm up the kitchen, I could also put TRV's on the bathroom towel rails as they can get pretty hot and the room stat is in the sitting room ( a data term box) which means that when the bedrooms and the bathroom reached the desired temp they would close down resulting in an increased flow to the down stairs dead legs but probably not enough to heat up all the downstairs rads. As I have always maintained the pumps I selected to run my system are not suitable ( silly me) what do you think about using one of the commercial pumps that I listed, i can vividly remember years ago I did put a big pump in the system ( i suppose I could find out which one but it would take me a long time) I even had to manufacture a plate with rubber mountings for the vibration noise and special connection hoses to the system) it worked ok, that's all I can say, anyone want to buy a Grundfos Alpha 3b 15 50/60 bought 4 months ago and has only just started to be used (no heating over the summer months)
Have a careful look at the pump power as iis possible that its pumping 0.65m3/hr (10.8LPM), if so the pump power will be 34W so carefully note this and then briefly shut the pump outlet valve and again note the power.
Just note the pump power as above "Have a careful look at the pump power as its possible that its pumping 0.65m3/hr (10.8LPM), if so the pump power will be 34W so carefully note this and then briefly shut the pump outlet valve and again note the power.
Even if you installed a 10M pump the flowrate (if any) will only increase by 30% (sqroot 10/6) so maybe from 10.8LPM to 14.0LPM, so checkout the power please.
Also if you only now changed to 100% CC from PP3 then the flowrate would only have been 7.9LPM at 3.15M. assuming the pump is running at 34w above.
Even if you installed a 10M pump the flowrate (if any) will only increase by 30% (sqroot 10/6) so maybe from 10.8LPM to 14.0LPM, so checkout the power please.
Also if you only now changed to 100% CC from PP3 then the flowrate would only have been 7.9LPM at 3.15M. assuming the pump is running at 34w above.
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Hi John thanks for your input, I need to shut down (my head is spinning from all that's going on) so as I told you I am getting on a bit, would it be possible to give me the settings for the pump so as to obtain the measurements you require, then I will shut the outlet down and record the settings again and we can take it from there thanks.
OK, (I'm getting on a good bit more than you).
Just put or leave the pump in CC (constant curve) mode at 100% which is the highest possible setting that will give the greatest circulation.
Leave what ever rads you have open to the circuit now and just start the boiler/pump and note the pump head in (meters) M, the flowrate in M3/hr and the most important one of all the power output in (watts) W. and then just shut the pump outlet valve for say 5 secs (boiler/pump running) and just note the above readings again, re open the pump outlet valve and if desired then shut down the boiler/pump. You may wish to post the first set of readings before doing the closed valve test.
Just put or leave the pump in CC (constant curve) mode at 100% which is the highest possible setting that will give the greatest circulation.
Leave what ever rads you have open to the circuit now and just start the boiler/pump and note the pump head in (meters) M, the flowrate in M3/hr and the most important one of all the power output in (watts) W. and then just shut the pump outlet valve for say 5 secs (boiler/pump running) and just note the above readings again, re open the pump outlet valve and if desired then shut down the boiler/pump. You may wish to post the first set of readings before doing the closed valve test.
Hi thanks John I get tired very easily these days with the problems associated with me being diabetic and problems with my knees and arms, I never thought that having arthritis in my arms would feel like I had bad toothache but it does with me been to the dentist and he pointed this out to me, will talk with you tomorrow if that is ok with you, got to get this sorted out before the cold weather sets in as this is another problem with being diabetic I cannot stand the cold, never mind.
Good morning John
Did like you said and the results from closing the outlet of the pump were no different than the previous results namely :- estimated pump head 5.9M, flow rate 0.0m3/h, power output 22watts
Did like you said and the results from closing the outlet of the pump were no different than the previous results namely :- estimated pump head 5.9M, flow rate 0.0m3/h, power output 22watts
Just to be clear
Pump definitely in CC3 mode and results with the pump outlet open were the same as with it closed, above, ie, 5.9M, flow rate 0.0m3/h, power output 22watts??, extraordinary as you are getting some circulation through the rads.
Also check that the pump inlet valve is fully open.
Just confirm the above please and I will have another look through the pump manual
Pump definitely in CC3 mode and results with the pump outlet open were the same as with it closed, above, ie, 5.9M, flow rate 0.0m3/h, power output 22watts??, extraordinary as you are getting some circulation through the rads.
Also check that the pump inlet valve is fully open.
Just confirm the above please and I will have another look through the pump manual
Yes John exactly the same, I had the same query how come the downstairs big radiator (upstairs closed) was heating up with a flow rate of 0.0m3/h dos'nt seem possible, the system is a sealed fully pumped "Y" plan
one
Doesn't seem possible, can you change to constant pressure mode CP3 which is a constant 4.5M, if not pumping in this mode then the power will read only 15W.
I did come across here sometime where a pump was displaying all the above symptoms but when the head was removed it was full of soft sludge with the impeller vanes choked, vanes can be cleaned with a tie wrap.
If its still not pumping on CP3, I would be inclined to isolate the pump and remove its head (2 or 4 stud bolts) complete with impeller and inspect it, then flush pump body ports alernatively tfrom he inlet and outlet valves, you will have to top up the boiler afterwards.
OR, if you still have the Alpha 2, simply install that and see will it pump, why did you replace it with the Alpha 3 as it has exactly the same performance but not the same amount of bells and whistles
If this pump was installed originally then you can look at this first for any signs of sludge inside, etc.
I did come across here sometime where a pump was displaying all the above symptoms but when the head was removed it was full of soft sludge with the impeller vanes choked, vanes can be cleaned with a tie wrap.
If its still not pumping on CP3, I would be inclined to isolate the pump and remove its head (2 or 4 stud bolts) complete with impeller and inspect it, then flush pump body ports alernatively tfrom he inlet and outlet valves, you will have to top up the boiler afterwards.
OR, if you still have the Alpha 2, simply install that and see will it pump, why did you replace it with the Alpha 3 as it has exactly the same performance but not the same amount of bells and whistles
If this pump was installed originally then you can look at this first for any signs of sludge inside, etc.
yes I have, another thing could my problems be associated with the outlet valve, why I say that is because the pump has the common connections on it but I have a gate valve just above it and I have been using that to close off the outlet and I have had problems with that type of gate valve before where the brass gate dose not fully open or fully close but sticks in one position.
Do you think that if I flushed out the whole system with a good cleaner it might do the trick?
i did notice you mentioned CP3, the pump was set in constant curve, so I reset it to CP3 closed the valve and the pump stopped, reopened it and the pump reset itself to constant curve, i have been using my wifes new phone but it keeps losing the connection with the pump and is very hard to reconnect
Yes, a prime suspect, its quite possibly closed now so if the threads arn,t stripped you should get 3 to 5 full turns anticlockwise from it , there's always a 1/2 to 3/4 of free play before they start to open or close.
Only as a very last resort IMO, get the pump working and we can see then if required.
If you do get it opened then leave it as Don,t require any more closed valve readings
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