Thermo Scientific Precision Premium PR305040G, Operating Manual

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To replace a defective safety relay, proceed as follows:
1. Disconnect power cord from the electrical outlet.
2. Open the chamber door. Carefully remove and retain hardware from
door hinges (case side). Set door aside.
3. Slide the oven forward until the front of the bezel (control panel) is at
least three inches from the edge of the bench top (or the oven feet are
at the edge of the bench).
4. Prop up the oven front by placing a shim under each front foot. Use
shims between 1½ and 2 inches in thickness.
5. Remove the screws securing bezel from bottom of oven.
6. Slide the oven back on the table plus a few inches (to set the bezel on
the bench) and rotate the bottom of the bezel out from the oven. The
top clips will come loose but the wiring will still be connected.
7. Carefully set the bezel on the bench.
8. Consult the schematic and locate the safety relay (mounted on bezel).
9. Remove four lead wires from their push-on terminals.
10. Remove two Phillips screws which mount the safety relay to the bezel.
11. Lift out the safety relay.
12. Generally reverse the steps above to install the replacement safety relay
and re-assemble oven.
Precision Premium Oven 6-9 Thermo Scientific
Section 6
Service
Replacing the Safety
Relay