Frequently Asked Questions
 

1. Closed systems operate a furnace at a psi of seven or more, therefore it is considered a totally pressurized system. Pressurized systems require much stricter guidelines for installation and operation.
   
2. Open systems operate a furnace with direct contact occurring between the outside air and the water in the furnace. This allows oxygen to get into the system and create proper conditions for corrosion and excessive evaporation to occur.
   
3. The HEATMOR™ bladder system allows little occurrence of evaporation and lessens the introduction of oxygen and other harmful elements into the system. It also allows the use of antifreeze and other coolant enhancement chemicals. Under normal operating conditions, a HEATMOR™ will operate at atmospheric pressure (3 psi or less). However, if a malfunction occurs (overheating) the specially designed pop-off valve will allow excess pressure to be relieved to the atmosphere.