HVAC replaced circuit board on my york gas furnace
New board has a green light that flashes continuously on/off about every 1 second
When furnace is running this light changes to red and flashes at same rate
Is this normal?

Look on the back side of the blower motor access door for a wiring diagram. The information you are looking for is located there in print. You will also find the flash code for future problem indication. If the furnace is running then all must be OK.

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