HRM Wallstar Oil Boiler - Advice please

[SJB060685]

If you have a weak spark then increasing the gap is likely to give problems, also a way of testing to see if the spark is weak. As always adjust to mi's

 

[Simonvr46]

Left heating engineer a voicemail. Burner wouldn’t start this morning took numerous attempts just kept going lockout. Gave up trying, left it for 10mins pressed reset and it started I just don’t get what’s causing it. It can be switched on for 6 hrs and it’ll run perfectly, it’ll stop when it gets to temp etc then restart every time. It’s just seems to be on the initial start up.

 

[SJB060685]

Hopefully the engineer will get back to you and you can mention everything we went through last night.

 

[Simonvr46]

Hopefully the engineer will get back to you and you can mention everything we went through last night.

Hope so.....
Spoke to HRM this morning, they said it could be electrode or could be to do with the air in the oil line and advised against fitting tiger loop. The way he was explaining the lockout that I’m having doesn’t appear to follow a normal pattern that you would expect for either air or electrodes.

 

[SJB060685]

I'm under the understanding that a tigerloop would void the warranty from new but your boiler is past warranty anyway. A tigerloop not only lifts fuel, it pre heats it and removes any gas bubbles in fuel supply. Having said that the danfoss pumps are more than capable of drawing fuel up to about 2.5m, even modern Riello pumps can draw fuel a certain distance. The engineer needs to thoroughly check electrode position going by the book, spark quality and whether or not its intermittently sparking elsewhere ie around porcelain protectors or HT lead. If after a number of attempts he is happy all is well then I would move onto checking atomization of fuel at nozzle, this again needs to be done safely and properly.

 

[John.g]

I assume its going through a normal pre-purge and 5 sec ignition before lockout, most burners do a 12 sec pre-purge followed by the oil solenoid energising and the ignitor/electrodes firing for another 5 secs, if no flame established after this 5 secs, 17 in all, then lockout.?
To completely rule out oil pressure problem on start up could you fit a oil pressure gauge and monitor this after failure, you can then concentrate on something else. Also after the 12 sec pre-purge you will hear a distinct "click", I don't know if this is the noise of the solenoid opening or the sound of the electrodes sparking but SJB will know this.

 

[SJB060685]

You are correct to a degree John. This is a Satronic control box so the timing sequence for ignition function and everything else is slightly different. The ignition is on from the start of pre purge and stays on till about 15 seconds after ignition. Putting a gauge on pump will tell you if you have pressure from the start. These Danfoss pumps have operating pressure from the word go, unlike Riello and some Suntecs which have a wash pressure. However the pump has been replaced so I shouldn't be the problem. If it was air in the fuel line I'd be expecting the pressure to be fluctuating up and down and not a solid 8 bar for example. Obviously if the inlet port to HP line was completely air locked then you'd have no fuel at nozzle, one of the reasons I said what I did above.
Yes solenoid have the very distinctive click when opening and closing

 

[Simonvr46]

I'm under the understanding that a tigerloop would void the warranty from new but your boiler is past warranty anyway. A tigerloop not only lifts fuel, it pre heats it and removes any gas bubbles in fuel supply. Having said that the danfoss pumps are more than capable of drawing fuel up to about 2.5m, even modern Riello pumps can draw fuel a certain distance. The engineer needs to thoroughly check electrode position going by the book, spark quality and whether or not its intermittently sparking elsewhere ie around porcelain protectors or HT lead. If after a number of attempts he is happy all is well then I would move onto checking atomization of fuel at nozzle, this again needs to be done safely and properly.

That’s basically what the guy at HRM was saying with regards to the electrode. He said to make sure that the diffuser plates in the blast tube are correct distance away from nozzle/electrodes as that can affect the nozzle pattern.
If the HT leads and electrodes are replaced then that’s everything apart from motor and blast tube.

 

[SJB060685]

That’s basically what the guy at HRM was saying with regards to the electrode. He said to make sure that the diffuser plates in the blast tube are correct distance away from nozzle/electrodes as that can affect the nozzle pattern.
If the HT leads and electrodes are replaced then that’s everything apart from motor and blast tube.

Yes the brake plate needs to be at correct position as well as like you say this will affect spray pattern, too close to nozzle outlet and it will affect its ability to ignite, or delayed ignition. MI's says 3-5mm but I'm sure I've mentioned this before?

 

[Simonvr46]

Hi john,
If you go back through these posts on here you will see a video of our burner going into lockout.
It’s just bizarre that it isn’t every time.
If it continually went to lock out and wouldn’t start i would be happier. I’d be even happier though if it started every time lol.
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Yes the brake plate needs to be at correct position as well as like you say this will affect spray pattern, too close to nozzle outlet and it will affect its ability to ignite, or delayed ignition. MI's says 3-5mm but I'm sure I've mentioned this before?

Yeah I did check these when it was mentioned before and they all seemed ok to within the tolerances specified in handbook.