Worcester Greenstar Heatslave 18/25 oil boiler.

[Christopher buzzard]

Hey. Fairly new to oil. Serviced above boiler Last week. All working fine but now had customer call to say it keeps going to lockout.
Been and looked today. Symptoms are the boiler ignition process will start. You can hear it sparking. The boiler will fire, run for around 1 min and flame will extinguish. It will then start sparking again but wont ignite. Then lockout happens. When you reset it will just spark and not ignite Before lockout again. if left awhile it will ignite again but goes through the whole process again. Nozzle was changed at service but changed again today to rule out faulty 1. The oil pump pressure is per MI. As is CO2 %. Oil filter clear. Spark gaps as per MI And photocell clean. Any suggestions would help.

Thank you.

 

[SJB060685]

What burner is it? Riello?
Have you ruled out fuel problem?
Try and drain a few litres of oil off at the pump, putting a vacuum gauge on as well will show a restriction.

 

[Christopher buzzard]

Its a bentone sterling 50 burner.
When i checked the filter i opened the valve and ran off about 1/2 litre and seemed to be ok. There’s a tiger loop on the system which is showing oil.
Its 1 of those jobs where the customer says ‘ it worked ok before you serviced it ‘

 

[SJB060685]

danfoss coil I would suspect at those timings if oil is genuinely sound

 

[SimonG]

Coil, the new ones are rated to a higher temperature, but not much better than the old ones.

Also what co2 did you set it too?

 

[SJB060685]

Coil, the new ones are rated to a higher temperature, but not much better than the old ones.

Also what co2 did you set it too?

The new diamond series are supposed to be better yes but I know a number of us who have had a lot of issues with them.

 

[SimonG]

The new diamond series are supposed to be better yes but I know a number of us who have had a lot of issues with them.

It's like everything new that's brought out. Chance to double the price without doubling the life. Or maybe I'm just too cynical in my advancing years

 

[Christopher buzzard]

@SimonG 12% For co2. 0.55 80 EH nozzle.
thanks for all your responses.

 

[SimonG]

I wouldn't run anything at 12%, 11.5% max for me on newer machines. Older ones 10 to 10.5%.

 

[SJB060685]

I wouldn't run anything at 12%, 11.5% max for me on newer machines. Older ones 10 to 10.5%.

I set up C02% to outside temperature as well as knowing the individual boiler installation. You are right that modern boilers can handle the increased %, especially with blue flame technology and other really clean burning burners but with this recent heat I would of been setting to the higher end.

 

[SimonG]

I set up C02% to outside temperature as well as knowing the individual boiler installation. You are right that modern boilers can handle the increased %, especially with blue flame technology and other really clean burning burners but with this recent heat I would of been setting to the higher end.

Still haven't come across a blue flame one yet.

 

[Christopher buzzard]

Even though MI states 12%?
when i was on probation The Oftec inspector made sure my readings were to MI so thats what I’m do on services.

 

[SJB060685]

Plenty of them out there buddy. Good clean burning burners, very little soot emissions and recirculate combustion gasses to reduce NOx emissions. Blast tube is designed for this recirculation and the centre of ignition is further forward in the tube.
[automerge]1597004398[/automerge]

Even though MI states 12%?
when i was on probation The often inspector made sure I’m readings were to MI so thats what I’m do on services.

Chris you are right to set to MI's but you'll see in each boiler manual a CO2% to outdoor temperature.
What you are doing is adjusting CO2% to the density of atmospheric air.
Experience of individual boilers and outdoor temperature with give you a point to work to.
OFTEC guy is right in what he says but experience will have burners running sweet all throughout the year.

 

[Christopher buzzard]

Thank you very Much For the advice. Hope to gain that in the coming years. Will report back once the boiler is fixed.

 

[Christopher buzzard]

Was the coil in the end. Back up and running. Thanks for all your help.

 

[SJB060685]

Was the coil in the end. Back up and running. Thanks for all your help.

Just remember that coil failure is common on danfoss pumps. It can go two ways 1. Break down due to heat and remain completely open circuit or 2. Break down due to heat and refuse itself after a little time. Either way a volt stick and solenoid tester would have proved that fault if you had them. Bare in mind a volt stick won't work on a Riello burner because its DC but a solenoid tester will prove an electromagnetic field regardless of whether its AC or DC supply.
The new diamond series danfoss solenoids are supposed to be better but I've known a number fail so I'm not entirely convinced they are better at all.