Understand a flashing SUPPLY indicator and other APS-3C status lights.
On the SCP-120 / APS-3C, a steady green SUPPLY light indicates power. A blinking green SUPPLY light means that the pavement-temperature sensor is missing or not functioning.
The manual requires that sensor to be connected to terminals 10 and 11 for normal operation. Have a qualified installer inspect the sensor and its wiring using the instructions for the exact controller revision. Do not assume that a blinking light identifies a specific resistance value or authorizes bypassing temperature protection.
- SNOW: a connected snow/ice sensor is requesting heat.
- HEAT: the control is calling for heat during a snow event, hold-on period, or manually started heater cycle.
- BAS: on the version covered by the linked manual, a building automation system is overriding local control. Earlier units may label this interface differently.
- TEMP LIMIT: the applicable high-temperature limit has been reached.
If the supply indicator continues blinking, contact WarmlyYours Technical Support at (800) 875-5285.
Sources
- Manufacturer instructions (publication 980), PDF pp. 4 and 7–8.