Central Heating circulation issue

[egizz983]

I am seeing TWO pumps now in post #8, time for the Jamesons.

post 8 is photoshoped as a example on where to place pump . post #34 basicaly all you wrote is correct . Bottom pipe on the left is return from rads to the boiler . top pipe from the left is from boiler and on the right is feed and into the radiator flow . the reason i installed like this because i had no space on the left side return to install pump after the boiler . so i installed before and put that NRV. also i noticed that on post #34 where it says pump direction market against the flow is that an error ?

 

[John.g]

In post #1 you can see the arrow on the pump pointing towards the wiring on the pump terminal box, in post #34 unless you have changed the pump head orientation then the pump is pumping upwards, is the arrow on the pump pointing upwards or downwards.

 

[egizz983]

post 8 is photoshoped as a example on where to place pump . post #34 basicaly all you wrote is correct . Bottom pipe on the left is return from rads to the boiler . top pipe from the left is from boiler and on the right is feed and into the radiator flow . the reason i installed like this because i had no space on the left side return to install pump after the boiler . so i installed before and put that NRV

In post #1 you can see the arrow on the pump pointing towards the wiring on the pump terminal box, in post #34 unless you have changed the pump head orientation then the pump is pumping upwards, is the arrow on the pump pointing upwards or downwards.

in #1 picture thats where it was when i created the post and it was pumping to the left towards the boiler . but then Shaun said its in wrong location and i relocate based on picture on post #4 and now its pumping downwards . i rotate motor as well to original position . as in #1i had to rotate motor to move wire out of the way because doors was not closing , when moves upwards i moved back to original position . i can be confusing sometimes sorry #1 how it was #18 how it is now .

 

[John.g]

OK, thanks, that will work only on the rads as if/when you remove the cylinder coil NRV, the pump will be pulling on the coil hot pipe and the water from the coil cold pipe will then tend to be pulled in as well which will upset the whole circulation and no heat to the cylinder as well.

You could move the pump to before the coil hot pipe and you it will then circulate through the cylinder coil and the rads, only downside is that the cold feed will now be to the pump discharge and will result in negative pressure in parts of the system, you could then move the cold feed to the pump suction but better off with no horizontal runs which may be difficult to achieve or you could take a T from below the pump where its installed now and pipe that back into the coil flow (top) which may be the better option?

 

[egizz983]

I would think that it should work if you install in the horizontal pipe just above it and shift the vent to the left of it, that way the cold feed is to the suction side of the pump and the whole system should operate at a positive pressure. As installed IMO, should still work but not the best as system will be at negative pressure in places.
Ideally, should have mot.valve and balancing valve on cylinder coil as cylinder temp will run at the boiler temperature otherwise.
Shaun is showing the pump on the flow from the boiler, pump pumping away from the boiler (correctly), but the above mod should achieve the same IMO.

Have you changed the pump settings?.

you mean like this ? the problem i would have this way that there would be not enough space to fit in pump unless i remove T and connect closer to vent going back to boiler flow

 

[John.g]

Option B?, leave the pump where it is and run a pipe teed in below the pump (outlet) and connect directly into the coil HW inlet after removing the T and inserting a piece of pipe in the horizontal pipe. You should be ae to run it in a way to allow the installation of a motorised valve later for cylinder temperature control.

 

[egizz983]

Option B?, leave the pump where it is and run a pipe teed in below the pump (outlet) and connect directly into the coil HW inlet after removing the T and inserting a piece of pipe in the horizontal pipe. You should be ae to run it in a way to allow the installation of a motorised valve later for cylinder temperature control.

Could you make a drawing i didt really get what you mean

 

[John.g]

What about this?, should work??

 

[ShaunCorbs]

Or just move the pump to the left and pipe up how I drew it

 

[egizz983]

Or just move the pump to the left and pipe up how I drew it

so i think your drawing is exactly how John drew in #43 i think . only thing is vent is in wrong position but does that effect anything ?"

 

[ShaunCorbs]

so i think your drawing is exactly how John drew in #43 i think . only thing is vent is in wrong position but does that effect anything ?"

If you look the vent is moved as well

 

[egizz983]

If you look the vent is moved as well

So if i do like John in that image i would need to put another T under flow to coil for vent . right ? does vent location make big impact on heating system ?

 

[egizz983]

What about this?, should work??

Would i remove NRV then ?

 

[ShaunCorbs]

Need to move the vent

 

[John.g]

So if i do like John in that image i would need to put another T under flow to coil for vent . right ? does vent location make big impact on heating system ?

You have a combined Vent and cold feed, one vertical pipe in effect, it should connect into the system on the suction side of the pump, reason is, when connected to the suction side, the pump suction will be at the elevation head (height) from the F&E tank surface to the pump suction, say 1.5M or whatever, the pump discharge head will then be pump head + the elevation head, a pump head of say 3.5M+1.5M=5M, all the system at positive pressure. If connected at the pump discharge the pump discharge head will be 1.5M and the pump suction, 1.5M - 3.5M, a negative head of 2M, most of the system under nrgative pressure.
So if you go for the first option you just move this vertical pipe to the left of the pump after also moving the pump as per your own post #40 and thats it. If you go for option 2, my post #43, then the vertical pipe is already to the pump suction and you run the pipe as shown to the cylinder HW inlet.

There is a plasic 1/2" pipe above the combined vent&cold feed, where does that go to? or is it removed and capped somewhere below?. Or ist blanked off and removed at the tank?.
Looks like the mains supply to the ballcock??.

Would i remove NRV then ?

You don't have to but its better to do so and replace it with a gate valve for balancing purposes and before you install (if) a motorized valve you can simply use the gate valve as a cylinder temperature control, on/off or whatever.

 

[egizz983]

You have a combined Vent and cold feed, one vertical pipe in effect, it should connect into the system on the suction side of the pump, reason is, when connected to the suction side, the pump suction will be at the elevation head (height) from the F&E tank surface to the pump suction, say 1.5M or whatever, the pump discharge head will then be pump head + the elevation head, a pump head of say 3.5M+1.5M=5M, all the system at positive pressure. If connected at the pump discharge the pump discharge head will be 1.5M and the pump suction, 1.5M - 3.5M, a negative head of 2M, most of the system under nrgative pressure.
So if you go for the first option you just move this vertical pipe to the left of the pump after also moving the pump as per your own post #40 and thats it. If you go for option 2, my post #43, then the vertical pipe is already to the pump suction and you run the pipe as shown to the cylinder HW inlet.

There is a plasic 1/2" pipe above the combined vent&cold feed, where does that go to? or is it removed and capped somewhere below?. Or ist blanked off and removed at the tank?.


You don't have to but its better to do so and replace it with a gate valve for balancing purposes and before you install (if) a motorized valve you can simply use the gate valve as a cylinder temperature control, on/off or whatever.

1/2 plastic pipe is feed to the tank from mains to Ball valve . Do you have picture of gate valve , as what i find on google is basicaly simple valves to close water . or is that what you mean by saying gate valve ?

 

[John.g]

A gate valve is simply a shut off valve with a hand wheel on top to open/shut.

 

[egizz983]

A gate valve is simply a shut off valve with a hand wheel on top to open/shut.
View attachment 78401

why would you need shut off valve there ? to close half way ? or why ?

 

[John.g]

If you have all the rads on and the HW cylinder then the cylinder coil which is effectively a 3/4 ins by pass can rob the CH side so that is used and maybe opened a 1/2 turn or so to reduce the flow through the coil and give more to the rads. I think its installation is frowned on now by the powers that be, I never had one on mine but I have a motorized valve and i generally programme that to come on for a hour or two before the CH so no problem but I don't notice in reduction in the rad outputs even with both on.
As I said you can use it temporarily until you install a motorized valve but you don't have to, its up to yourself.

 

[egizz983]

If you have all the rads on and the HW cylinder then the cylinder coil which is effectively a 3/4 ins by pass can rob the CH side so that is used and maybe opened a 1/2 turn or so to reduce the flow through the coil and give more to the rads. I think its installation is frowned on now by the powers that be, I never had one on mine but I have a motorized valve and i generally programme that to come on for a hour or two before the CH so no problem but I don't notice in reduction in the rad outputs even with both on.
As I said you can use it temporarily until you install a motorized valve but you don't have to, its up to yourself.

Okay thanks a lot will see how it goes tnx for help And Shaun