8. Verify that the unit is not in a purge cycle. This can be done by verifying a flow of air
into zone 1. Read the (PRES) reading in the diagnostic screen (write down reading).
9. Connect the tubing from Reference Gas regulator to Zone 1 on the manifold of HGM
300. Note: The Fault light on HGM300 may illuminate until gas starts to flow
from the reference bottle to unit. The pressure should be below the original reading
(if reading does not drop the unit may be in the purge cycle. If so wait until purge cycle
ends then continue). Adjust the variable regulator slowly clockwise until pressure is
the same as original reading. Note: You may have to block or partially block the
relief valve on the variable pressure regulator in order to achieve the appropriate
pressure. Allow about 1 minute to settle then read the first PPM value in the
diagnostics screen. The reading should be within +-10% of the concentration indicated
on the reference bottle. NOTE: The unit may go into a purge cycle during the test
process. If this happens, the PPM reading will drop to approximately 0PPM. This
does not affect the verification results. However in order to obtain a valid PPM
reading, the unit must be drawing from zone1.
10. Close reference by adjusting variable regulator counter clockwise until fully closed.
Reset zone 1 information (distance, refrigerant, zone hold time) as desired for normal
operation.
11. If reading in step 9 is not within the +-10% of the PPM reference bottle please check
the following:
- Verify pressure from step 8
-Check that tubing is securely connected to the reference bottle and Zone 1 input port
-Verify proper gas is selected (step 5)
-Verify unit is in hold for zone 1
-Verify verify proper pressure from variable gas regulator (step 9)
-Verify that ample time was given for readings to stabilize
If the unit still does not measure within +-10% of the Reference Gas PPM, please
contact the factory.
Rev 3/2/09
17
