Temptek VETERAN LS Series, Instruction Manual

Page: 50 / 80

Temperature Control Units : With ‘LS’ Series Instrument
Page: 50
TEMPTEK, INC.
525 East Stop 18 Road Greenwood, Indiana 46142
317-887-6352 Fax: 317-881-1277
Service Department Fax: 317-885-8683
www.Temptek.com
as outlined in section 3 of this manual.
5.7 PRESSURE SWITCH SERVICE
A. The unit is protected from low
pressure operations by a pressure
switch (figure 5.7A). This switch
is mounted at the bottom of the
electrical cabinet.
B. The switch will close and consent
the control circuit when sufficient
water supply pressure is presented.
The switch is factory set to 20 psi.
C. If insufficient water supply pressure
is present, the switch will open and prevent operations.
D. In cases where sufficient water supply pressure is present as
indicated by the unit’s pressure gauges and the pump is “off”, and
if the pressure switch fails to close, the pressure switch may be
defective. To replace the pressure switch, follow the steps outlined:
1. Shut down unit operations according to section 3.4 in this
manual. Be certain proper lock-out procedures are followed.
Also, be certain system pressure is eliminated and the unit’s
pressure gauges read “0” pressure.
2. Drain unit by removing the pump casing drain plug.
3. A capillary runs from the cooling cylinder to the pressure
switch. Remove the capillary connection.
4. The brass elbow mounted on the pressure switch must be
removed.
5. Remove the electrical connections to the pressure switch.
6. The pressure switch is mounted onto the electrical cabinet
with two 1/2” nuts in series. Remove the nuts to remove the
pressure switch. A new pressure switch from the factory
should be installed by continuing with step 7.
7. Thread one 1/2” nut onto the pressure switch and then
place the pressure switch through the panel in the original
mounting hole. Thread the second 1/2” nut from the bottom
of the pressure switch. Tighten to lock the pressure switch
in place.
8. Install the brass elbow fitting. Teflon tape and leak
preventative paste should be used to prevent water
Pressure switch
Figure 5.7A