DJ2700 low fuel gas flow

[guang]

Our DJ2700 system has worked 8 years. Recent years a serious problem about the fuel gas flow happened. Our lab use propane as fuel gas and we use heater and vaporiser to heat the propane, the gas pressure can usually reach 100 psi. But the problem is that the propane gas flow is never higher than 20 FMR. This puzzle me. Can any one give some ideas? Thank you!
The pressure and gas flow rate of air, oxygen and propane are 100psi/55FMR, 150psi/30FMR and 100psi/15FMR respectively now.

[Gordon]

Hi Guang

If you are maintaining 100psi propane pressure and have no liquid propane in the lines there should be no problem.

Check and calibrate regulator, flow meter, and flashback/non-return valves.
Check hoses are free of any restrictions that may impede flow.
Check gun and syphon plug for flow restrictions.