Heater is actually ok now.. I think it was a combination of the change in season and a clogged check valve that caused the temp to spike and not the heating system. I turned it off for 3 weeks and the temp stayed higher than normal the entire time. I checked the valve and there was rust particles stuck inside it.
The heater is back on and the temp is back into range again. I will be looking for that stainless steel model sooner than I thought I think.