The "call for service" is from your Acadia and would stay there until reset. For example if a temprature fault (either bad sensor or even overtemp due to low charge of refridgerant) occured - the "call for service" would stay lit until reset. With emergency heat on - if wired correctly the WE signal from the TS joins the WE signal from the Acadia and both wire to the W2 (high electric strip heat) at the York TS. The W1 coil is powered from the Acadia side giving max electric strip heat - which is still less than the Acadia delivers but should keep the pipes from freezing.
The fact that the fan outside is not spinning seems to indicate that the Acadia had a volitile lockout and shup off. Are you sure there is no error code at the Aca?