pumping over when hot water selected

[andyf]

fully pumped system, sunvic 3 port valve,grundfos 15/50 pump,worcester greenstar boiler.
I've noticed recently that the vent pipe to the F&E tank is producing a constant trickle of water when I select for hot water alone or heating & hot water. Heating alone does not produce this flow. I also noticed quite a bit of sludge in the tank,much of it orange. I've changed the diverter valve actuator with no effect and the valve itself moves quite freely. I've turned the pump down to 2 but it still happens.
Must there be a blockage in the hot water tank or somewhere?

 

[seco services]

probably a restriction/blockage.
try running a magnet around the cold feed/vent pipe where it joins
the system just before the pump.
see if it sticks.

 

[ducatikid]

Either sludge in system or pipework configuration not good. You say orange sludge in f&e , was the system flushed that you know? When the 3 port was changed what condition was the water in? maybe a treatment of x400 for a 3/4 weeks followed by x100 and see how you go. Good luck.

 

[seco services]

maybe a treatment of x400 for a 3/4 weeks followed by x100 and see how you go. Good luck.

x800 better than x400 and no good using x100 till problem solved.

 

[twgas]

A partial blockage is likely where the cold feed/open vent join the system.

 

[ducatikid]

x800 better than x400 and no good using x100 till problem solved.[/quote]

Would have no problems recommending x400 to the normal diy'er , especially when most times no machine available to them. I understand x800 is not only for use with machines , but I suppose personal preference and all that. As for x100 to be added , whether fixed or not , it can still have a positive effect on the system and will certainly not advance the problem for a tenner money well spent , imo.

 

[seco services]

Would have no problems recommending x400 to the normal diy'er , especially when most times no machine available to them. I understand x800 is not only for use with machines , but I suppose personal preference and all that. As for x100 to be added , whether fixed or not , it can still have a positive effect on the system and will certainly not advance the problem for a tenner money well spent , imo.

as you said x800 don't need a machine and will work quicker than x400
in shorter time.
9/10 times a blockage will need to be cut out as x800 or x400 won't shift it.

why stick x100 in if system needs draining again or problem not fixed ?

 

[Servotech]

fully pumped system, sunvic 3 port valve,grundfos 15/50 pump,worcester greenstar boiler.
I've noticed recently that the vent pipe to the F&E tank is producing a constant trickle of water when I select for hot water alone or heating & hot water. Heating alone does not produce this flow. I also noticed quite a bit of sludge in the tank,much of it orange. I've changed the diverter valve actuator with no effect and the valve itself moves quite freely. I've turned the pump down to 2 but it still happens.
Must there be a blockage in the hot water tank or somewhere?

Try turning the pump down to 1, it's ample speed for most domestic heating systems and could be all that's required.

 

[ducatikid]

why stick x100 in if system needs draining again or problem not fixed ? [/quote]

Not trying to contradict you on this just want to explain my reasoning

As you said X800 or X400 both have the same properties , would have to say personal preference due to job results would probably be up to each individual , I've found both to be grand.

As for leaving some X100 in the system whether fixed or not , this is simply due to the potential length of time the system will be left before permanent fix is made.

 

[andyf]

Thanks all. I cannot detect any obvious magnetic areas in the pipework around the F&E,pump etc, would it be obvious?.
I did consider turning the pump down to 1 but the pump has always been at 3 and it's a slightly larger house (14 radiator panels in all) and was concerned the boiler may come to harm if the setting was too low.
I think the pipe layout is ok as the system has been trouble free apart from a change of pump/valve/motor and eventually boiler in 20years+.
I haven't changed the actual diverter valve yet, just the motor. I changed the valve itself about 4 years ago.
I'll try some system cleanser. Is it best to drain system before refilling with cleaner added?

 

[seco services]

do no harm to flush the loose out first and you see the condition of the water before adding your chemical.

 

[logan34]

Hi,
Most likely a blockage.
Run a magnet around the cold feed/vent pipe where it connects. Thanks

 

[45yearsagasman]

View media item 55283this is the most likely place for a blockage, which would cause your symptoms. I always cut this section out and repiped for a 100%cure.

 

[polesapart]

Hopefully resolved since 2010

 

[Madrab]

Not doing too well @logan34 , that's the 2nd post you've replied to that is more than 10yrs old.

You need to check the post dates before replying.