Controller And Boiler Not Talking To Each Other

[gordon_k]

Hi all... new here -

I have a Ferroli Maxima 35 S condensing system boiler, operated via a Drayton Lifestyle LP241 digital controller.

This combination has been working fine since I moved here about two-and-a-half years ago; but in the last few days, the boiler has stopped responding to the controls, and now just stays on all the time.

The controller looks OK - display is lit and seems to function normally; if set to timer, its hot water and heating lights go on and off at the programmed times - but the boiler stays on regardless, so I've had to just switch it off using its own on/off switch.

Have tried pressing the "reset" button on the boiler, also tried switching it off for ten minutes or so, then back on again. But as soon as I switch it back on, it just fires up and stays on, regardless of what the heating controller is (or ought to be) telling it.

Is there anything I could try which might fix this - some sort of fuse that might have blown between the controller and the boiler?

Just want to explore all possibilities before calling out a central heating engineer...

GK

 

[NozSpark]

So you also have a motorised valve or two?

I would guess that one of them is stuck open (either mechanically or electrically) and is sending a false demand signal to the boiler.

I doubt that you'll fix this without carrying out some electrical testing.

IMHO It's time to get an electrician in who's familiar with heating controlls.

 

[kerching]

As Noz says, geta spark,in who IS experienced with heating controls.

I know itbsounds silly...but a lot of electricians cannot understand heating controls.

FFS there are some who ask questions on here who I Would not let fix a sundial...never mind something with elecktrickery involved

Just saying

 

[Andy™]

FFS there are some who ask questions on here who I Would not let fix a sundial...never mind something with elecktrickery involved

r.b springs to mind...

 

[kerching]

I am saying nothing

Just saying, or not,,really

 

[Sharpend]

Can't agree more with the lads, make sure the spark is familiar with heating controls, only this week I've had to diagnose a fault for a colleague based only from pictures he had taken for me as the Sparks who MOVED his programmer up the wall by a foot or so wired it back incorrectly!!

 

[gordon_k]

Cheers guys -

Yeah, I'm guessing there must be motorised valves somewhere. Between the control unit and the boiler there is also a Lifestyle wiring box ("Danger 230V") with various cables coming in, and two cables (both electrical by the look) running to the boiler.

So, from what you're saying, is it fair to conclude -

1) There's not much a electro-klutz like me could usefully do

2) I'm almost certainly looking for a (heating-controls-savvy) electrician - rather than a gas/plumbing dude ?

 

[steptoe]

yes,

you deffo need an electrician with a knowledge of heating controls,

and you deffo do NOT want a plumber that thinks he knows what he is doing,

as above,

be aware of just getting any electrician, a LOT do NOT know anything of heating controls,

they are NOT proper electricians.

try and get a recommendation.

 

[Doc Hudson]

Welcome to the forum Gordon. Where about in the country are you? Maybe one of the guys on here is nearby or knows someone local to you. Your problem does sound quite likely to be a valve related issue. The timers and thermostats drive a motor that operates the valves. Once the correct valve has opened a small micro switch inside the valve sends the call for heat to the boiler. When the timers & thermostats are switched off, a return spring should close the valve and disconnect the heat call when the internal switch opens. If the valve is mechanically stuck open, or the switch is stuck on, the boiler will be continually firing irrespective of the timer or thermostat settings.

Doc H.

 

[ProDave]

Well if you are intent on a DIY fix, you could try replacing the actuator head for any motorised valve(s) you have.

Be sure to buy EXACTLY the same part, take a photo of how the old one was wired BEFORE you disconnect any wires. and TURN THE POWER OFF before you start.

Trouble is that's not a guaranteed fix so may be a waste of money.

One thing to try first is remove the actuator head from the valve body and see if the heating turns off then? it could be the valve body that's stuck. If that's the case it's a job for a plumber.

 

[gordon_k]

Cheers guys -

I have got a recommendation for a reliable local guy who specialises in central heating, and it sounds like whether the valve problem is electrical or mechanical he will be able to deal with it.

Thanks for clarifying the issues for me - that's been helpful.

Gordon