RE: Gas rate and burner pressure

[PlumbingSucks]

Hi been to service a gas fire cleaned everything out but gas rate is fine bang on but burner pressure is 14 and should be 17 +/-0.75 mbr. How come? any
ideas please

 

[Toddyplumb]

Which type of manometer did you use ?

 

[PlumbingSucks]

Water as broke my digital one. Zero'd it of course.

 

[fuzzy]

is there a restrictor tee?

 

[kirkgas]

there could be a blockage in the test point pipe, which is restricting the flow to the u gauge, but isnt effecting the gas rate/usage at the burner

 

[GrahamM]

Is the work/op pressures ok?
How old is fire? It is possible that the injectors are of the incorrect size or have been bored out slightly by cleaning using welding nozzle cleaners. Therefore you will get a bit more gas burning, allowing the gas rate to be within limits, but may have a lower than normal burner pressure.