Ideal RS330 and cool radiators....any help appreciated

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Back at my parents to try and sort out “Cold/Cool” radiators downstairs...well trodden ground I know, sorry !

Basic Semi; Ideal RS330 boiler – all radiators on one zone, 4 upstairs (2 small) and 3 downstairs so nothing really that should cause issues.

Upstairs all hot, downstairs all pretty cool although the inlet side of the first one pretty hot.

Hoping they may just have been a “bit bunged up” I've remove all the downstairs ones and flushed them out – still not getting hot. If I close off the Dining Room/Lounge the final one in the circuit does get hot but as soon as I open the others back to square one. I've played around with balancing as best I can including closing all the one off upstairs with no noticeable effect either.

Pump is [edit' I think] running but I'm wondering if that could be the issue ? The Boilers internal thermostat also seems to kick in quite a bit. Unfortunately the pump isn't that accessible as its under the kitchen floor and the access he made has shrunk in size since I was a bit younger !

Any insight / suggestions would be much appreciated ?

Thanks, FF
 
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Could be a straightforward balancing issue. See FAQ number 5 here.

Thanks, I've tried balancing using the lock shields on each radiators but with no great effect – the CH system as it is is pretty much as it has been for 30/40 years+ probably – it doesn't seem to be a true “feed and return” system as it were though with each radiator just T'd off the supply from the boiler which works around and returns to the boiler through the pump.



It's worked over however many years though and don't recall it ever being a problem when I was a kid at home.
 
Do all downstairs rads have TRV or wheel head valves as well as a lockshield ?
When you removed each rad to flush, did you open both valves on each rad ,to ensure water flowed freely from each rad valve . That would have verified that the pipework was not blocked / restricted.
I assume the system is not sealed , but fed from a small F&E tank ?
If the rads and pipework are clean ,the pump would be a likely suspect.
 
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TRV's: two do, one doesn't - an old style "non convecting" type (that I should replace !).

Good wash through - using both inlets/outlets (made a simple adaptor for my hose) and removed both top plugs - upside down, shake it all about so ran clean as best I could I reckon !

Not sealed - just one single F&E tank. Was that normal rather than two for a house back in the 50's ?

Thanks again, appreciated.
 
Did you allow water to flow out of each VALVE ,with radiator not on the wall ?

Thanks Terry.

Yeh, I'm I opened each one when off (I think it was each) - catching the flow in a washing up bowl ! I'm pretty certain there is flow from each.
 
Then you have a circulation issue and the first thing to examine is the circulator ( pump) which may not be working . Show us a picture of it .
 
it doesn't seem to be a true “feed and return” system as it were though with each radiator just T'd off the supply from the boiler which works around and returns to the boiler through the pump.
That sounds like a 1-pipe system.

View media item 17739
The water temperature entering the radiator decreases the farther you get from the boiler, so radiators have to be increased in size to compensate. Balancing is also completely different from a 2-pipe system
 
Then you have a circulation issue and the first thing to examine is the circulator ( pump) which may not be working . Show us a picture of it .

Its a Grundfos, it's on the return after the last downstairs radiator (and return from upstairs I reckon) before the boiler but just out of reach from the access for under the floor – I need to get under to reach it and it's a tight squeeze for me now as it is ! I can make it a bit larger though.
 

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That sounds like a 1-pipe system.

View media item 17739
The water temperature entering the radiator decreases the farther you get from the boiler, so radiators have to be increased in size to compensate. Balancing is also completely different from a 2-pipe system

Thanks for the diagram - yes from what I can see that would be how it is and realise that the further you get away from the boiler the cooler the temp might be...

..what might be the best way to try and balance this type of system (if its not the pump ?)

MTIA.
 
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Can't you remove the floorboards that are above the pump ? Or at least reach to the large chrome screw in the centre of the pump. Removing that screw ( with electrics switched off) will allow access to the pumps shaft / spindle ,to see if it's turning freely.
 
Can't you remove the floorboards that are above the pump ? Or at least reach to the large chrome screw in the centre of the pump. Removing that screw ( with electrics switched off) will allow access to the pumps shaft / spindle ,to see if it's turning freely.

Sadly no - that's under the kitchen and tiled !

It's just over an arms length (mine anyway) away...I reckon I'll have to make the access more suitable to my "frame" !
 
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That sounds like a 1-pipe system.

View media item 17739
The water temperature entering the radiator decreases the farther you get from the boiler, so radiators have to be increased in size to compensate. Balancing is also completely different from a 2-pipe system

Just going back to the increasing size; Dinning room is 1st, double - Lounge follows which is larger again double (both Stelrad but that's not really relevant) followed by the Hall which is the older "ridged" type (no convection fins) and in volume maybe between the two. It's not a massive run and all pipes underfloor appear to be insulated.

Thanks.
 
Now having access under the floor the pump (Grundfos USP 15-60 130) which looks to have been replaced in 2013 seems to be running OK.

It's fitted horizontally with the outlet side slightly higher than the inlet although it is pretty much at the lowest part of the system – pumps always been there although as far as I know.

Removed the vent plug and checked the impeller moved OK – switched back on and ran and it was spinning OK with a narrow squirt of water being thrown out.

Of the three settings it's on No 1.

Ho hum, should perhaps I'll try II although why since recently does it seems to have been working OK ?

MTIA for any further help.
 

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