Thermo Scientific 180 Series, Руководство по эксплуатации и техническому обслуживанию

Страница: 25 / 36

7-2 GP Water Baths Thermo Scientific
Section 7
Service
Replace Thermostat
(Within the Pan)
Use the following thermostat replacement procedure when the sensing
bulb is located WITHIN the bath pan. Some models only have externally
mounted sensing bulbs on the underside of the pan. If this is the case, refer
to the procedure following this one.
Caution Care must be exercised when handling the thermostat capillary,
since a sharp bend will crimp off the flow of the hydraulic operating
medium. To avoid twisting the capillary or damaging O-ring, hold the
fitting under the bath stationary, and firmly tighten locknut inside bath
chamber. Do not over-tighten, as O-ring could be squeezed out of
position, causing bath to leak. Undertightening will also cause the bath to
leak.
s
1. Put switch in "OFF" position and disconnect power to bath.
2. Remove shelf and drain bath.
3. Remove thermostat control knob by loosening two set screws on knob.
4. Place bath on its side and remove bottom plate and insulation to gain
access to thermostat fitting.
5. Remove two screws fastening thermostat to control panel.
6. Remove wires from thermostat terminals. Mark location of wire leads.
7. Hold the fitting under the bath stationary, unscrew locknut inside bath
chamber, and remove from capillary.
8. Feed thermostat capillary out through hole in bottom of chamber.
9. Replace O-ring on bottom side of chamber with new Viton O-ring.
10. Complete installation by reversing above procedure. Be certain all
wiring is away from heater. Insulation must be replaced between
heater and bottom plate to prevent possible wire shorting.