Very very Hight Co2 ppm old Myson velarie... Help

[bacon_sandwich]

ahh didn't know its the same motor that runs the pump, still the cap value is so low it must be the run cap. single phase induction motors need a cap, some have a start cap and a run cap, some just a run cap.

 

[SimonG]

Capacitors a start capacitor. Other than change a nozzle the black silver and orange ab burners I tend to leave alone.
Far too much air. Oil pressure about 115 psi maybe a touch higher.
Check the nozzle is in properly and tightened up.

 

[oilmark]

I find the air settings on the aluminium band very sensitive to adjust. Like Best says they collect dust and fluff, make sure that's cleaned off. Could air be entering elsewhere?
There should be an air diffuser around the nozzle.

 

[RayPlumb]

I find the air settings on the aluminium band very sensitive to adjust. Like Best says they collect dust and fluff, make sure that's cleaned off. Could air be entering elsewhere?
There should be an air diffuser around the nozzle.

Thanks. Im going to check to see if air getting in somewhere else, and clean band. Tell me more about the air diffuser. There definitely was not one there. How much difference does it make.? Is it something i can make without or do i need to make one up..washer.. what sort of diamiter . Would one work from another burner. .?

 

[RayPlumb]

Just stumbled across this . Looks like my troublesome burner. Cant see a diffuser washer behind nozzle on it or am i mistaken. Is this the same burner for myson valarie ..?

 

[Best]

There is no separate air diffuser on that burner.
It is a one piece blast tube and that tends to make it much better and not complicated

 

[oilmark]

Best is right, no separate diffuser. I have managed to reassemble the burner with the nozzle not in the correct central position! Ie not in the circular holder, if you see what I mean?
Sounds like too much oil or not enough air though.

 

[oilmark]

Is the plastic bit replaced near the oil pipe to nozzle?
No. 17 on diagram.

 

[Best]

Probably the most common burner I have worked on until recent years when Riello became more prevalent.
The blast tube is removable by slackening the 2 grub screws and makes the nozzle easy to work on without risk of damaging it

 

[RayPlumb]

Is the plastic bit replaced near the oil pipe to nozzle?
No. 17 on diagram.

The plastic bit, no 17, locating block... No not replaced this. What is it for? I did not access through bank plate.

 

[Best]

The plastic bit, no 17, locating block... No not replaced this. What is it for? I did not access through bank plate.

No 17 part is to hold the nozzle assembly centre at the front of burner (to keep the nozzle at other end straight) and no 17 also adjusts the nozzle distance to front of diffuser. (It has a bolt threaded through it to pull nozzle out and in.
Do not adjust it!

 

[SimonG]

But he only has a couple of rashers at a time.

 

[RayPlumb]

Update on boiler. Got there this am with new capacitor. On arrival noticed lock out on..Odd considering I had switched off at wall and at boiler and told client not to use boiler.. Different story..
Re-cleaned the now oil wet combustion chamber..*?@*%
Removed burner and removed fan and cleaned loosened air band and cleaned. Found small stone jammed in back of band preventing it closing fully. So when I thought I had closed air band there was actually gap at the back. TOO much air... So with that sorted . I replaced nozzle thanks to Kris's Myson performance data sheet, and set pressure. Done smoke test at low air and adjusted down to 2 smoke. Then fine tuned with FGA. Ended with 11.2 co2, 37% excess air, flue temp 277 C, 70 co ppm. any more air to bring co2 down a bit then co ppm rises. Not sure what the recommended co2 is for that boiler.
Anyway happier with that. All that headache from a 2mm stone..
Must say the air band is very fine movements to tune in. I ended up at just under 1 on the settings.

 

[RayPlumb]

What is the advice around switching off unsafe boiler. I was taught that with oil we have no legal right to disconnect boiler. but if pumping out co @ 800ppm... Surely.. I told client on Friday boiler not safe and do not switch on, 3 times I told him. Could not believe when he said he had it on. Luckily it locked out...

 

[SimonG]

What is the advice around switching off unsafe boiler. I was taught that with oil we have no legal right to disconnect boiler. but if pumping out co @ 800ppm... Surely.. I told client on Friday boiler not safe and do not switch on, 3 times I told him. Could not believe when he said he had it on. Luckily it locked out...

Did you document it was unsafe to use?

I'll pull the fuse and turn the oil off. Document unsafe, get them to sign and keep a copy. After that its up to them.

 

[RayPlumb]

Yes put it on a job sheet that I start before starting job. Would normally get them to initial any changes etc. I get then to sign and authorization to proceed before I start any job. Client had left before I finished and not back before I left, so phoned client and explained all to client before I left and he seemed happy.. Should have waited until they returned to sign, but next job waiting...

 

[RayPlumb]

Thinking about it I could of put an Oftec warning sticker on it and taken a picture. I dont need a clients signature for that.

 

[Best]

What is the advice around switching off unsafe boiler. I was taught that with oil we have no legal right to disconnect boiler. but if pumping out co @ 800ppm... Surely.. I told client on Friday boiler not safe and do not switch on, 3 times I told him. Could not believe when he said he had it on. Luckily it locked out...

I turn switches off and sometimes remove the solenoid to prevent burner firing.
Fuse out and oil off for extra safety.
Can’t trust customers or friends they bring later to interfere. Or children obviously can be at switches.

 

[RayPlumb]

I turn switches off and sometimes remove the solenoid to prevent burner firing.
Fuse out and oil off for extra safety.
Can’t trust customers or friends they bring later to interfere. Or children obviously can be at switches.

Ill keep that in mind. Ill take solenoid with me. For better piece of mind.

 

[Best]

Update on boiler. Got there this am with new capacitor. On arrival noticed lock out on..Odd considering I had switched off at wall and at boiler and told client not to use boiler.. Different story..
Re-cleaned the now oil wet combustion chamber..*?@*%
Removed burner and removed fan and cleaned loosened air band and cleaned. Found small stone jammed in back of band preventing it closing fully. So when I thought I had closed air band there was actually gap at the back. TOO much air... So with that sorted . I replaced nozzle thanks to Kris's Myson performance data sheet, and set pressure. Done smoke test at low air and adjusted down to 2 smoke. Then fine tuned with FGA. Ended with 11.2 co2, 37% excess air, flue temp 277 C, 70 co ppm. any more air to bring co2 down a bit then co ppm rises. Not sure what the recommended co2 is for that boiler.
Anyway happier with that. All that headache from a 2mm stone..
Must say the air band is very fine movements to tune in. I ended up at just under 1 on the settings.

You don’t want the Co2 much more than 11% for that burner.
There was some of them supplied with a slightly different blast tube and you will find it had to burn slightly higher smoke number to achieve reasonable CO2.
I have the actual paperwork for the Velaires, but can’t be bothered looking for it.