White-Rodgers 50A65-475 circuit board. LED is continuously off indicating no power. However, the fan runs continuously.
My suspicion is that lightning may have fried the circuit board. Everything *was* working before. It is possible that the A/C is working but I'm not 100% certain; the temperature does drop though slowly, perhaps. However, the heat never starts and again, either way, the fan runs continuously.
The LED is supposed to flash once when power is first turned on as it does its self-check but now nothing happens.
I don't want to replace the circuit board (50A65-475) until I can absolutely confirm that is the problem. I am a little confused that the fan runs continuously when power is on to the system. Is that on a different circuit with a default of "on"? The thermostat fan setting is "auto", not "on".
Is there an obvious test I can try (with a multi-meter, perhaps) to verify the circuit board needs to be replaced? Is there something else that might be the issue here?
If I do have to replace the circuit board, will any 50A65 do? It seems the 475 model has been superseded. Finally, where's the best place to get a replacement? I found a 50A65-843 on an HVAC website for about $190. Should I be able to do better than that?
Many thanks in advance for all help.
My suspicion is that lightning may have fried the circuit board. Everything *was* working before. It is possible that the A/C is working but I'm not 100% certain; the temperature does drop though slowly, perhaps. However, the heat never starts and again, either way, the fan runs continuously.
The LED is supposed to flash once when power is first turned on as it does its self-check but now nothing happens.
I don't want to replace the circuit board (50A65-475) until I can absolutely confirm that is the problem. I am a little confused that the fan runs continuously when power is on to the system. Is that on a different circuit with a default of "on"? The thermostat fan setting is "auto", not "on".
Is there an obvious test I can try (with a multi-meter, perhaps) to verify the circuit board needs to be replaced? Is there something else that might be the issue here?
If I do have to replace the circuit board, will any 50A65 do? It seems the 475 model has been superseded. Finally, where's the best place to get a replacement? I found a 50A65-843 on an HVAC website for about $190. Should I be able to do better than that?
Many thanks in advance for all help.