My wife wanted me to disable the End-of-Cycle buzzer in our laundry machine (dryer) for various reasons. I thought it would be an easy enough task, but it has since turned into a learning experience. Unfortunately I know just enough about circuit design to get myself into trouble by thinking I understand it. Enough context though and on to the actual question…
See the schematic below for reference. I removed the EOC Signal, indicated in blue. I then bridged the connection (bridge depicted in yellow) and wired the Push to Start Switch directly to the Control timer, circumventing the EOC Signal. This caused the Thermostat Hi-Limit Right, indicated in red, to fail dramatically after about 5-10 minutes of running the dryer. Very likely that the dryer reached it's end of cycle.
What I'm wondering is why this happened. My best guess is that, normally, the timer sends a high energy signal to the EOC Signal when the cycle is over. However, because I removed the EOC signal, this high energy signal made it's way back to the Thermostat Hi-Limit Right and overloaded the component.
Additional information,
The EOC Signal has a flag note that reads:
EOC signal will sound when timer is in cool down period of cycle and during extra care cycle. It operates with singal on 5 seconds and off 70 seconds. To test-set timer near end of cycle or in extra care cycle and wait 2 minutes for signal to sound. Timer must be allowed to run, and electrically energize signal.
The model is a GE GTX33EASK0WW. Assembly Diagrams can be found here: https://www.geapplianceparts.com/store/parts/assembly/GTX33EASK0WW?ModelType=ModelType
The buzzer part number is WE4M318, Dryer Buzzer – Diagram No. 89
The thermostat part number is WE04X26139, High limit thermostat – Diagram No. 507
EDIT: At the recommendation of @manassehkatz, I disconnected the two wires coming off the EOC Signal (buzzer) and capped the ends. It worked like a charm. No more loud buzzer, much happier wife.
Best Answer
As @brhans noted, you effectively made a short-circuit of the EOC buzzer. Buzzers can fail, and I suspect designed normally to fail open. If you wanted to exactly replicate the circuit, that would require putting in a resistor equivalent to the resistance of the buzzer. But most likely the dryer is designed so that buzzer failure will not prevent the rest of the dryer from operating properly, so removing the buzzer and capping the wires would have been sufficient.
Hopefully the Thermostat Hi-Limit Right was the only sacrificial component to this short circuit, but you may not know until you replace it.
My old Kenmore (really made by GE or Whirlpool, not sure which) has a knob to control the EOC buzzer sound - including "Off", but you're not so fortunate.
Adjusting sound level is probably not practical. But it would be easy enough to wire up an On/Off switch for the buzzer. However, it would need to be designed for 120V usage - i.e., like a full light-switch in a junction box with proper insulated wires, not a "little" switch despite it being "only a buzzer".