help....please experts on open vented system needed...

[bobster]

Hi,
I have an OV system, old boiler would start and turn off after 5-10 seconds, removed sludge by hose pipe flush, changed 5 of 10 radiators, changed tempreture sensors, ended up changing to a new boiler! Changed the pump, added a magnacleana, added a air seperator,.....still have the same problem... have spent 8 hours today power flushing.....same problem, wiring seems ok as call for heating works, call for hot water works, at my wits end...... boiler is a potterton suprima 60 he. Could this be an air lock? how do you identify an air lock?

thanks

 

[fuzzy]

the new boiler also turning off after 5/6 seconds?, is there a block or valve turned off on the flow?

 

[bobster]

hi new boiler is also turning off after 5/6 seconds. The valves on the pump are open, but i dont how to check if the 3 port valve is opening i can certainly here it, sounds like it is functioning? could it be the wiring? or if the wiring was wrong, would the call for heat not work? etc?

 

[fuzzy]

if there was no call for heat then it wouldnt turn on in the first place, is the flow pipe hot? ive had it happen when the heat cannot get away, ie a shut valve on the boiler not just the pump, have the rads ever got warm?
the three port, what type is it? it will always have a route, maybe not the right one but should always have a route

 

[Toddyplumb]

Make sure you have an air vent on the flow pipe above the boiler or that the pipework rises all the way to vent !
If you have an elbow on top of boiler flow , change it to a T with vent.
Also check live and neutral are correct

 

[bobster]

hi sorted, flue was from old boiler and blocked, now cleared its all good. thanks all

 

[ferret]

WHAT !!!! you are kidding with the flue from the old boiler right , are you saying the new HE boiler is using the old flue??

 

[bobster]

no old boiler was HE exactly the same, whilst testing had the issue, with the new flue it was fine, hence looked at old flue and found it was blocked, so that cleared up what the issue was.

 

[Avatar]

Jesus man that is a lot of work to solve a very simple problem - did you not call in an expert to look at the system.

If I came in, I would have called in a heating eningeer I work with to look at the boiler, as for you initial description it would seem to be were the problem was.

Look before you leap, and certainly find the fault before you start swapping compenents on the system.

Sounds like you have been taking shots in the dark on this one . . .

Next time call in the proffessionals!

Christ!!!!!!

 

[fuzzy]

glad its sorted, dont often think of a flue blockage these days, should have known hey!

 

[bobster]

Avatar, I had professionals look at a number of problems to solve. With the first boiler, the flue was fine there were some other gremlins!!! The situation evolved over time, and at the end of the day. its like getting the whole lot reset to zero, which is what it needed I think, the system must have been 20 years old. Trust me there was a hell of a lot of sludge in it, and the boiler never worked properly. Anyway its all over now! thanks for you help.

 

[Avatar]

If you had someone look at the original boiler flue - then they should have been able to diagnose and fix the problem for you.

Like I said, I am not a boiler expert, but if I had a look at the system for you given the sympoms I would have brought my boiler expert in, to look at the flue/gas supply and internal components of the boiler, before recommending expensive work elsewhere on the system . . .

 

[moony]

boiler cutting off after 5-6 seconds - blockage somewhere in the line, whether it be in the pipework or the flue....


like you say its been basically renewed throughout now so more piece of mind than anything else. Wish i had a customer who wanted a powerflush, 5 new rads and a new boiler without me checking the flue lol - least youv e got piece of mind now.

 

[gasmarc]

you are aware that what you have done is illegal , it is against the law to use an old flue with a new boiler ?

 

[Avatar]

Good point!

 

[bobster]

Avatar, thanks for your some what obvious advice, ofcourse an expert looked at it before parts were changed, it just that there was more then one problen to solve, the old boiler had its own issues, with thermistors, sensors, PCB. The whole system was sludged up, the pump did actually completely go etc etc. Christ.......where do you find professional advice!