He can't fix it so I'm suppose to replace my oil boiler. Really?

[fadedspark]

Yes, I was reading about a similar problem someone had on another post with solenoid. I'm going to order one and a boiler stat and see from there, plus flush the system and add a new inhibitor. I think it is related to an overheating problem somewhere.

 

[Johntheo5]

If it was a boiler (water) overheat problem then you would have had to reset it, item 38, the only reset you have to perform is to reset combustion failure, if the boiler control stat is clicking on/off at ~ 10C hysteresis when you turn it up and down then probably OK as well but no harm anyway in replacing it.
I run my 18 year old SE Firebird, Riello G5X burner, at 75C and the temp does rise to ~ 95C after cut out but has never caused a problem since the O/heat stat operates at 110C/113C.

 

[fadedspark]

I actually think the boiler stat is working because it fires up if I turn it up to a higher setting providing it is not locked out.

For the last few hours, I've been running the rads by pressing the hour boost button on the timer with the programmed settings switched off. I've left fifteen minutes between each switching on of the boost and it's fired up three times without a lockout problem so far and the boiler temp control is set about halfway.

I get the feeling this is one of those annoying intermitted problems that you just have to catch at the right time to finally crack it. Throughout my working life, I found nothing more irritating than those intermittent problems.

 

[fadedspark]

An update:
The last two mornings the boiler has been switching on with demand, except for this morning. But every evening it has refused to start on demand. Every time it has refused to start on demand the burner reset light has been on except for this morning when the light was off. Every time I press the burner reset once it fires and runs until demand switches it off.

I've been through the electric side of things again and can find no fault at the time of testing. All the stats and coil seem to be working when tested.

I think I'm looking at either an oil pump sticking problem of which I'm doubtful, or an intermittent fault with the control box. I thought it could be an intermittent fault with the coil but I've taken it off and tested on it its own power supply about 50-60 times and it works every time.

Any comments much appreciated.

 

[Johntheo5]

Some of these coils have two supplies from the control box, one to open the valve and the other to hold it open. My 530 SE controlled coil has a resistance of (just measured) 1450 ohms (nominall, new is 1400) and there are 3 wires in it blue, browm & black. when I remove the control box and probe from brown to blue 1 to 2, I get 1450 ohms and the same when I probe from black to blue, 8 to 2 so yours may be similar, if it has 3 wires then you you would need a low voltage supply as well as 230V? to really test it. May be worth just renewing it.

 

[fadedspark]

Mine is two wires, with resistance at 100 ohms which according to worcester info is spot on. I have one on order, for the cost it's worth replacing, if it's not the problem I've got a spare.

Control is over £120 though so ruling everything out first before buying that.