Myson Midas - slow ignition (occasionally)

[HizerKite]

Hi, am posting this as a last resort before I throw in the towel and replace my boiler I could really do without the expense so am hoping for some help.

I have an old Myson Midas Si combi boiler. I've kept it going for years by fitting various parts (sensors, boards etc) but now it has developed a fault that I think may signal the end.

The fault is this:

If the boiler has been off for some time (a few hours or overnight) then when it first fires up there is a delay. On startup the 1st relay (pilot) clicks and you can hear the spark being generated but it may take 5 - 6 seconds for the pilot to light. Then when the 2nd relay (main burner) clicks the main burner struggles to ignite and makes a roaring noise until it lights completely. Once lit all is ok.

When the boiler has been running for a while it works correctly with the pilot igniting almost instantly then the main burner quickly too.

I'm pretty sure the fault is the gas valve main solenoid as I'm told this is opened 1st then the pilot, then the main burner. Does anyone have any other idea as to the cause? The only other possibility I came up with is the ignition board relay but this was recently fitted (with a reconditioned unit) so I doubt is faulty. I would have the gas valve replaced (won't touch it myself) but they are obsolete so not an option.

Any help is greatly appreciated as I'm really hoping to avoid the expense of a new boiler.

Many thanks
Richard

 

[Agile]

It seems you have not used a competent boiler engineer to service/repair your boiler.

As its a gas related problem, I cannot give you detailed advice on an open forum and can only suggest you try to find someone familiar with your very old boiler.

As for a repaired PCB not becoming faulty, all I can say is that even though it has been repaired ( not reconditioned! ) its still old and thus likely to fail again in a short time.

Of all the possible faults that can aflict your boiler I would not expect yours to be very serious. But your problem will be to get anyone who is knowledgeable enough and prepared to work on it.

I have not been to one for at least a year now and I hope that they have all been replaced by now.

Tony