Changing oil burner nozzle size and pressure setting

[noah813]

burner uses 1.2 80 degree B nozzle at 100 psi, I want to change to .85 80 degree B what should the pressure be set to? Set it to 100 psi or higher?

 

[oilhead]

Why do you want to change the nozzle? Are you derating the boiler or looking to get the same output?

 

[noah813]

My friends burner says it should have a 1.2 at 100psi in it and when we checked it had a .85 and I want to set the pressure up , not sure what it is right now waiting on meter. Either 100 psi or set it up to 140 psi or in between. Thanks

 

[oilhead]

Start at the beginning.
What boiler do you have?
What output has it been set to?
What burner do you have?
The same model of burner can be used on many different appliances. Burners are designed to provide a range of outputs, and the manufacturers instructions will specify the size of nozzle and operating pressure for the range of outputs and the fuel used.
When the boiler was commissioned, the technician should have detailed the settings and the combustion results.

 

[noah813]

He has a wgo-04
was with 1.2 100 psi stated on label
Now has a .85 at ? psi now, have to check with gauge
Beckett unit on it.

 

[oilhead]

Just noticed your flag, so don't recognise the boilers. However, the basics are the same. Establish the output required, check it is within the design range of the boiler and the burner. Assuming an efficiency gross of 85% and decide how much fuel you need to produce it. Consult the nozzle manufacturers charts for discharge volume at varying pressures. If using kerosene, you will be operating at a pressure between 100 -140, whereas with diesel 150-180. Both general areas of operation.