Altec AIR MHT Series, Owner'S Manual

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6
DRYER CONTROLS AND SAFTEY SHUTDOWNS
HOW TO MAKE MINOR REFRIGERANT SUCTION PRESSURE ADJUSTMENTS .
Keep dryer running under a no load by turning OFF or bypassing the compressed air.
Remove dryer top and locate the Hot Gas Bypass Valve. Remove cap on Hot Gas By-
pass Valve and turn valve counter clockwise to decrease the suction pressure and
clockwise to increase the suction pressure.
Make ½ turn adjustments and wait 2 to 3 minutes for suction pressure to stabilize.
Make more adjustments if needed.
HIGH PRESSURE SHUTDOWNS WITH MANUAL RESET
Shuts the dryer down in the event of a dirty condenser, fan motor failure or
excessively high ambient temperatures (Installed on UA150/MHT100 and
above)
LOW PRESSURE SHUTDOWN
Shuts the dryer down in the event of low ambient conditions or if there is a
leak in the refrigeration system. (Installed on UA400/MHT200 and above)
START UP
The following procedure must be followed to start your air dryer. Failure to follow this start up proce-
dure will void your warranty. If problems occur during start up, contact Altec AIR or your local distribu-
tor.
1. Turn the ON/OFF switch to the OFF position.
2. Verify the main electrical supply voltage matches the voltage specified on the data label.
3. Check the proper connection and support of the compressed air lines to the dryer: check dryer by-
pass and isolation valve system.
4. Confirm that the inlet and ambient air temperature, pressure and flow to the dryer meet the speci-
fied requirements.
5. Confirm that the condensate drain lines from the separator are properly piped to an environmentally
approved disposal system