Potterton boiler

[paulc7617]

Hi,as above we have a Potterton "normal" boiler i.e. not a combi! you will gather im not technical,we have lived here 15 years same boiler age unknown.No problems till last winters cold spell,when it dipped below freezing boiler would not ignite itself.When weather is ok boiler is ok ,now this recent cold snap once boiler knocks off i.e. timer it will not come back on automatically,i have to go in garage and press a button underneath and it reignites.I presume something to do with frost-stat next to boiler also in garage.Any help would be appreciated.

 

[cowley]

You don't say what model it is but it sounds like the button your talking about is the overheat reset on a Profile, the frost stat has nothing to do with this, it's an overide of the electrics to fire boiler to stop it freezing when everything is turned off.
If the o/heat is popping out it usually indicates problems like poor circulation, boiler stat, lack of water etc.

 

[twgas]

the frost stat has nothing to do with this, it's an overide of the electrics to fire boiler to stop it freezing when everything is turned off.

If the frost stat is wired directly to the switched live, and the by-pass in less than spec it may cause this problem.

 

[cowley]

Only guessing on Model, but good point I believe MI stated 3metres 22mm pipe run for bypass on these, maybe system getting a bit blocked.

 

[paulc7617]

Thanks for replys lads,will check model no tomoz and report back.cowley the button i press maybe what you say,but why does it only occur in freezing temps? works fine at all other times i.e. not poor circ, lack of water,stat.Not disputing what you say,you guys are the experts,just somehow dunt seem right.Cheers

 

[cowley]

When frost stat operates in cold weather the flow will only being going around bypass as twgas suggests so if this is blocked or restricted, or not as spec the boiler will overheat and button will pop out.

 

[paulc7617]

cowley thanks again,if it is what you/twgas say it is can I/gas repairman remody it.

 

[twgas]

It may be as simple as opening a by-pass valve.
There should be, after the pump but before the motorised valve(s) a tee that goes to the return pipe with a manual valve in it. If so turn the heating on and see if any heat goes through it, if none open the valve, slowly until it gets hot both sides of the valve.