Central Heating circulation issue

[egizz983]

should be installed like this

port valves are essential ?

 

[egizz983]

I see the pump is on Auto setting, you might change that to a higher setting and post the make/model of the pump, most pumps, Grundfos etc just don't work on this Auto setting. Also the cylinder coil NRV should be removed IMO (if still installed) especially if a spring loaded type but try pump on different setting for a start.

if i take off NRV then it stops circulating . i would guess i need to redo feed and pump location . Put pump on flow before boiler and feed before pump like in example ShaynCorbs send

 

[ShaunCorbs]

port valves are essential ?

Yes else your overheating / no control over hot water and hot water isn’t pumped

 

[John.g]

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?.

 

[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 shouachieve the same IMO.

Have you changed the pump settings?.

Yes i tried to set to max but as soon as i take out NRV its stops circulating or atleast ot doest pump hot water from boiler though the system .

 

[John.g]

If the flow&return are as shown and directions correct and the cold feed is shown correctly then suggested mod should work IMO, there are hundreds of installations like this with the pump mounted high up at the cylinder some with a mid position valve close by. To get the system up and running you can always install the zone valve later but maybe install balancing valve with next mod. I don't have one (but do have a Mot.valve) and a 6M pump running at 3.5M can circulate 10 rads + the cylinder coil.

The most obvious question of all, are the flow and return pipes connected to the correct boiler points?.

I,m still a bit puzzled as to why the original installation (pump on return) didn't circulate through the rads as essentially it was the same as my system except that my pump is pumping into the boiler (return) at ground level and adjacent to the boiler, the cold feed is connected in exactly as yours is.
Two attic bedroom rads do run with a slight negative pressure but its never been a problem.

 

[ShaunCorbs]

If the flow&return are as shown and directions correct and the cold feed is shown correctly then suggested mod should work IMO, there are hundreds of installations like this with the pump mounted high up at the cylinder some with a mid position valve close by. To get the system up and running you can always install the zone valve later but maybe install balancing valve with next mod. I don't have one (but do have a Mot.valve) and a 6M pump running at 3.5M can circulate 10 rads + the cylinder coil.

The most obvious question of all, are the flow and return pipes connected to the correct boiler points?.

I,m still a bit puzzled as to why the original installation (pump on return) didn't circulate through the rads as essentially it was the same as my system except that my pump is pumping into the boiler (return) at ground level and adjacent to the boiler, the cold feed is connected in exactly as yours is.
Two attic bedroom rads do run with a slight negative pressure but its never been a problem.

The pump is on the rad circuit only john

 

[John.g]

Original pump location (on the return) achieved no rad circulation, why not.
Second pump location only achieves limited rad circulation but only if cyl coil NRV installed, also strange.
Where should it be installed if my suggestion above incorrect?.

 

[egizz983]

Original pump location (on the return) achieved no rad circulation, why not.
Second pump location only achieves limited rad circulation but only if cyl coil NRV installed, also strange.
Where should it be installed if my suggestion above incorrect?.

if i get this right i would need to move ether on return or flow but after or before boiler ,bypass valve . then have 3 way motorized valve that diverts either to cylinder or rads , and keep that NRV on return ? that would solve all problems i guess as it would heat up ether rads or cylinder first and then would switch to the other one . or ofc i 2x two way valves . but i though all this should work ether way without putting those 2 way valves as old houses dont have them

 

[John.g]

Where was the pump installed when you had the stove?