I have a weil mclain he 2 hydro system.. 2 zone separate thermostats 2nd floor of my home is not getting heat blowing cold... circulating pump is working fine... pressure is about 12lbs... the control modual is blinking limit... which from what I have read
MIGHT
Indicate a bad return water temperature sensor... can this be the cause of the problem??
If so where would this sensor be located and would anyone have a possible picture