Why is my heater light flashing?

A flashing supply light on any APS or EUR-5A control indicates a missing or broken High Temperature Limit sensor. This sensor is required to make the EUR-5A controller to work. The sensor is not polarized and must be connected to pins 1 and 2. Refer to figure 9 in the...

The controller is oscillating – How do I fix this?

Install a 100K Ohm resistor in-line with the Equipment Ground terminal (19). Disconnect Equipment Ground terminal (18). Grounding The EUR–5A sensor circuits and the EMC inputs are referenced to a common circuit ground. In most situations, this part of the system can...

What are the BEMC connections for?

BEMC stands for Building Energy Management Computer, which can be used to remotely monitor and control the EUR-5A controller. These connections are made to pins 10 through 16. The following diagram will aid in making these connections. See page 9 of EUR-5A manual....

Can I simulate a sensor call for heat to test the system?

Yes, to test the system by simulating a sensor call for heat, connect a short jumper wire between terminal block terminals 25 (sensor signal) and 24 (sensor ground). Now the Heat LED should turn on within 10 seconds and the control relay should close. If the Heat LED...