How to Fix / Troubleshooting

Safety first: Turn off power at the breaker before removing the control panel.

Verify symptom: Turn the suspect knob through its range. If the element is either off or full power with no intermediate control, the regulator is likely faulty.
Access switch: Remove the control knobs and front panel to expose the infinite switches.
Inspect wiring: Compare wiring to the Gram wiring diagram. Correct any miswired connections.
Test switch: Using a multimeter, check continuity between common and output terminals at different knob positions. Lack of change or permanent continuity indicates a defective switch.
Replace regulator: Install a new energy regulator/infinite switch of the correct rating for that zone.

Warning: Ensure the replacement switch matches the original's electrical rating and shaft type.

Electric hotplate or radiant zone heats only on maximum or does not regulate temperature properly.

Possible Causes