- 15 -
Section IV Operation
Start Up
Before starting the unit, double check all electrical and plumbing connections
and make sure the circulating system (the CFT, the instrument being cooled,
and the tubing that connects them) has been properly filled with cooling fluid.
On units with a circuit breaker located on the rear of the unit, ensure it is the
on position. To start the unit, place the POWER Switch to the on (
I
) position.
The refrigeration system and the recirculation pump will start. The POWER
Switch illuminates (except for the CFT-150) to indicate the system is operat-
ing. Units with PD pumps display the pump operating pressure on the RECIR-
CULATING PRESSURE gauge.
To turn the unit off, place the POWER Switch to the off (
0
) position.
COOL indicates the status of the refrigeration system. It illuminates to indi-
cate the refrigeration system is removing heat from the cooling fluid. As the
operating temperature approaches the temperature setpoint, the LED will
flash. IDLE indicates the unit is in a hot-gas-bypass mode of operation. As the
operating temperature approaches the temperature setpoint, the LED extin-
guishes.
When the unit is shut off, wait approximately five minutes before restarting.
This allows time for the refrigeration pressures to equalize. If the pressures
are not allowed to equalize, the compressor will short-cycle (clicking sound)
and no cooling will occur.
Digital Temperature Controller
COOL
IDLE
YES
NO
NEXT
ENTER
°C
Summary of Contents for CFT-150
Page 15: ... 14 Blank page ...