MF200 PRESSURE PAL Hydronic Mini System Feeder (6 Gallon) The ‘PRESSURE PAL’ is ideal for feeding and pressurizing closed hydronic systems that do not require cold static fill pressures higher than 170 kPa (25 psig). It is compatible with both water and glycol/water solutions. Perfect for small boiler/chiller systems, snow/ice melt circuits, outside air heating/cooling glycol coils, solar heating systems