Applied Air IOMDFCDFM-1, Руководство по эксплуатации

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Checking The Burner Velocity Pressure
PS-10 & PS-11 air switches are factory calibrated.
Do not adjust.
The permissible pressure range should be marked on
the switches. If it’s close to the high or low trip points of
the airfl ow switches, you could have nuisance burner
shutdowns. High Velocity Switch open means too
much velocity and Low Velocity Switch open means
not enough velocity across the burner profi le plates.
Check the velocity pressure by disconnecting both
pressure sensing tubes from the High Velocity Switch.
Connect your manometer to each sensing tube so you
can measure the differential pressure and then enable
the fan.
CAUTION: Be sure to turn the power and gas off
to the unit before you access the burner. Follow
proper "lockout/tagout" procedures.
Some adjustments can be made by repositioning the
burner profi le plates. If the velocity will allow the High
Velocity Switch to open, you can open the profi le
plates. If the velocity will allow the Low Velocity Switch
to open, you can close the profi le plates.
REMEMBER
to keep the opening between the burner and profi le
plates the same on both top and bottom of the burner
when making these adjustments.
Depending on the motor amps, you may want to
change the speed of the fan if the unit has adjustable
sheaves.
Enable the burner and get it running in high fi re – See
Section X in this manual. Your differential pressure
should now be lower. If it is near the Low Velocity
Switch trip point, you need to increase the velocity.
The ideal velocity is in the middle of the High Velocity
Switch and Low Velocity Switch trip points.
Don’t forget to remove any jumpers and reconnect
the sensing tubes to the switch.
Call the factory if you have any questions.
TROUBLESHOOTING GUIDE