Thermocouple Labeling And Locations - Thermo Scientific Harris MBF-700 Installation And Operation Manual

THERMOCOUPLE
LABELING AND
LOCATIONS
Thermo Fisher Scientific
4. Replace the R290 cylinder with R508b.
5. Loosen the refrigerant supply hose at the gauge manifold; crack
open the refrigerant tank valve and purge the hose for 2 seconds,
then tighten the connection while purging.
6. Slowly open the gauge manifold High Pressure valve until the
system pressure reaches appropriate pressure close manifold gauge.
Or, weigh in the appropriate amount of refrigerant.
7. If the 1st (high) stage was charged, start the system and let it run for
15 minutes; measure / record thermocouple readings.
8. The Heat Exchange thermocouple should measure -35°C - -46°C. If
not, adjust the TXV until the desired temperature is achieved.
9. Connect the 2nd(low) stage start relay if necessary, and allow the
2nd stage to start.
10. Allow the unit to run for three hours with a temperature setpoint of
-95 °C.
11. Measure and record the temperature display and all thermocouple
values.
12. Thermocouple #3 is on the evaporator inlet and should measure
-87°C or colder, if not verify operation of the 1 st(high) stage system.
13. Thermocouples #4 and #5 are on the evaporator outlet and should
be within 2 °C of each other, and should be within 3°F - 6°F of
thermocouple #3. If not, adjust the charge by adding R508b
Thermocouple Label
A
B
SECTION 400 – MAINTENANCE AND SERVICE
Location/Description
'A' Heat Exchange Inlet
'A' Heat Exchange Outlet
Generic MBF700 Service Manual 53