Georgetown 364ts 2016. Dual heat (front/back), front malfunctioning

[iculus]

Hey all, first time poster here. We have a Georgetown 364ts. It has 2 zones for heat. Front and back. Seperate heat boxes and blowers. Having an issue where the the rear system works but the front does not. Independent thermostats. The front seems to cycle on three times, fan blows cold air through bottom ductwork, and then shut down. Is there a flame sensor we should evaluate? Or similar? Looks like it's all one unit. Would like to avoid service visit if possible.

Thanks!