Water pressure has a "red line" at 50lbs on the 2" OB pressure gauge. Lately pressure is down to almost zero after several days. There is a regulating value at the water supply line with a manual override to fill/increase the pressure. What is the normal pressure for this type of system? Is the regulating valve bad?
Fuel is oil
System is 20 years old
Bioler is a Weil-McClain (SP?)
Heats only base board no domestic water heat exchanger