Bakery Chiller Models PMC 40/50 and PMC 70/120
Effective February 23, 1999
Installation and Operation Instructions, Part No. 9842311
Revised May 7, 2009
7.5
Thermal Expansion Valve (TEV) Superheat Adjustment (Continued)
3.
Utilizing an R-22 or R-507 Pressure Temperature Chart, convert the suction pressure reading from
Step 1 to saturation temperature.
4.
The superheat value is found by subtracting the saturation temperature determined in Step 3 from
the actual suction line temperature taken in Step 2.
5.
If the superheat is not in the range of 8 to 10°F, at conditions as described above, adjust the TEV.
6.
If the superheat is below 8°F, turn the TEV’S adjustment stem clockwise
1
/
8
to
1
/
4
of a turn. Allow
the system to operate for 5 minutes before repeating test.
7.
If the superheat is above 10°F, turn the TEV’s adjustment stem counterclockwise
1
/
8
to
1
/
4
of a turn.
Allow the system to operate for 5 minutes before repeating test.
8.
Any time adjustment is made to the TEV, the refrigerant charge should be checked.
9.
Check the superheat setting and make final adjustments at a product temperature near setpoint for
best performance.
7.6
Thermal Expansion Valve Superheat Adjustment Diagram
18
TEV
Sensing Bulb
Thermometer
Suction Gauge
Liquid Line
Sight Glass
Thermostatic
Expansion
Valve
Liquid Line
Service Valve
Suction Line
Service Valve
Bakery Chiller
Air-Cooled Condensing Unit
Suction Line
Liquid Line
