Kingisher bad combustion

[mfgs]

I have to go and look at an old kingfisher next week which someone has capped off due to have 6000ppm of CO on combustion analysis. Apparently the flue is pulling well, its just burning really badly. Other than the basic cleaning the burner, heat exchanger and checking the gas pressure. Are there any other little tricks to get these burning nicely? I will obviously be checking the flue slow, spillage and ventilation.

 

[Gasmk1]

where did he check the co it is open flue i presume, never had a problem with these boilers easy to service just carry out full checks as you said clean burners heat exchanger always check gas pressure if it was making that much co i would expect it to be sooted up so be prepared.

 

[bright spark]

Burner could have cracks in it.
Injectors could be clogged with dirt.
God knows

 

[Last Plumber]

Proper strip down service. Once you take burner out any probs should be fairly obvious.
Check BP
Check ventilation
Air intake to burner etc

 

[lame plumber]

initial test then clean and test. mind you do the MFIs stipulate an fga test or just bp and gas rate and visual on the flame picture?

 

[jtsplumbing]

If you know anything about these old type boilers they are simple to service , remove burners, brush out flue ways, check how flue is pulling, check for air vent into room, fit new thermocouple, adjust burner pressure, waste of time using fga, you will know if its ok by the flame picture.

 

[spike.gb]

Assuming you are talking about an open flue model I'm sure I remember having an extended FGA probe years ago to test these when I was on the Gas Board. There was a technical bulletin saying you had to test at least 2 foot up flue because of spurious readings if tested lower, as long as flue pulling ok and spillage test pass.

 

[Stoney Ground]

I am take an old Kinfisher CF45 out in a couple of weeks, does anyone know if flue was asbestos, and will normal safety precautions be ok or will it need specialists.

 

[Last Plumber]

And remember there is a draft diverter at the back so you will be testing secondary flue products not primary

 

[mfgs]

Yeah its the open flue model. From what my customer has explained there is a draught diverter on the flue above the boiler and that's where the previous engineer tested from. Also apparently there were lots of "iron filings" in the gas pipe. So maybe the burner/injectors are slightly blocked or the gas valve could be a bit knackered.