Leaky valves were wasting compressed air and bypassing heat through the building circulation system into the return lines. This caused the boiler and compressor to keep operating when not needed. The other pneumatic controls that were not operating were not allowing the system to set-back at night. This alone could save 30% of the heating costs.
The main air handler filtration system was badly clogged preventing adequate return and supply off the condensers. This caused excessive load during operation as the four stage system could not get enough air to condition the space.