Downstairs Radiators not working

[Caesar]

Hi All

Sorry about the long post but really need help!!!

Had a chap put some inhibitor into system Fernox MB1 via Upstairs and downstair radiator. Then upstairs radiators would not heat up no pressure or water from then when being bled. Boiler engineer advised boiler is fine and that Cold Feed Pipe is blocked. Another engineer took pump out and blew down cold feed pipe form where F&E tank is water flowed very freely no blockage there. Engineer blew down 22mm pipe connected to boiler but said blockage probably in pipe somewhere there. Engineer refilled system and now upstairs radiators have pressure and water. Heating system now heats up upstairs Rads fine BUT downstairs rads are now stone cold! Engineer suggested powerflush but this was done 3 years ago and water was extremely clean when system was drained! Pump checked and appears to be running fine as spindle bounced screw driver off it! 3 Port valve maybe faulty as lever runs without any resistance when system is on or off!

Please can someone tell what the problem maybe and why downstairs radiators cannot get hot? Is it Pump, 3 Port Valve or airlock still in downstairs circuit? Many thanks in advance.

 

[seco services]

3 Port valve maybe faulty as lever runs without any resistance when system is on or off!

If heating was last call then the valve willbe held in last position ie heating.
no resistance on lever.
To get resistance on lever either hw needs to be last call or system electrics isolated and hw/heating off at programmer and elecy turned back on.

Please can someone tell what the problem maybe and why downstairs radiators cannot get hot? Is it Pump, 3 Port Valve or airlock still in downstairs circuit? Many thanks in advance.

Try closing the hot rads to use full flow to downstairs rads that'll clear any airlocks then you can reopen upstair rads.

 

[coytech]

hi
i would def turn all upstairs rads off and turn on heating only at control/clock if they come on you need to open upstairs rads slowly untill evenly balanced all over,if still not check valve is opening fully and not stuck or just moving slightly due to age or debris.if still no joy you may have to get a pro in!

 

[Caesar]

Hi Seco Services / coytech


Many thanks for your replies. If I shut down the upstair Radiators the Boiler shuts down! Could this indicate an Airlock or a blockage?

Before the upstairs Radiators had no water or pressure but since dismantling the pump and cleaning out the Cold Feed Pipe the downstair radiators do not work. Is it possible blockage has just been moved around the system to different point that stops downstairs radiators from working? Many thanks.

 

[Caesar]

Hi All

Anybody know what the problem maybe as now the upstairs radiators which I managed to get going by refilling the system will not work anymore! Therefore upstairs and downstairs Radiators do not work! Hot water is OK and Pump appears to be working although a little hot! Many thanks.

 

[NEALDEAN]

When you say the boiler shuts down, do you mean it goes off normally on the stat or does is lock out ?

Sounds pumpy to me !!!
Pumps can be very deceptive, if it's old I would replace it !!!!

 

[Caesar]

Hi NealDean

That is the thing that when upstairs Radiators were working and were then shut by closing one valve on each Radiator to pass the flow of heat to the downstairs radiators that was when the boiler locked out I think!

 

[NEALDEAN]

I would try pump.

Good luck

 

[moggridgeplumbing]

Sounds like air in pump possible problem.

 

[Caesar]

Hi All


My Thanks to all, just an update, left heating system alone for 1 night, next morning fired up boiler and surely but steadily heating came on although had to bleed both upstairs and downstairs radiators so certainly looked like blocked cold feed pipe and air lock problem!

Some radiators slightly cold at bottom so looks like an X800 Job which I will leave in system for a few days , flush a few times afterwards and add inhibitor or is it better to remove each rad and flush or should I have the system power flushed professionally?

 

[NEALDEAN]

Hi All

or is it better to remove each rad and flush or should I have the system power flushed professionally?

Would be cheaper to replace the pump

 

[JohnD]

If you think you have a sludge problem, it will do not harm to take off the easiest radiator (quite a small one), tip it into a bucket, take it into the garden and hose it through while banging it with your hand or a rubber mallet, see what comes out.

If a lot, or it is thick or hard lumps, do the others as well. If not much and it is runny, I wouldn't bother.

If you decide you have a sediment or sludge problem, it is worth splashing out an extra £100 or so to buy a filter/trap such as Sentinel, Spirovent or Magnaclean. The Magnaclean is spectacularly fast as trapping black particles, but tends to leak after a few years as it has poor-quality parts and is made of GRP. The brass Spirovent product appears to me to be far better quality, but does not work so fast. If you fit a filter before adding the cleaning chemical, it will trap whatever comes loose and circulates in the water. A filter will trap future particles to prevent them causing a new blockage, but will not remove existing sediment unless you loosen it with a chemical.