ROTARY HEAT EXCHANGER PTY LTD- SENSIBLE HEAT
Heat exchange wheels (rotary regenerative heat exchangers) suitable for air-to-air recovery of thermal energy from building exhaust air streams shal be of Rotary Heat Exchangers Pty Ltd www.rotaryheat.com or equivalent approved.
The Heat Exchanger rotor media shall be polyethylene - terephthalate film (Mylar) and the rotor matrix will have a depth of only 10cm and the rotor rotational speed limitted to a low 18 rpm. This thin rotor and low rotational speed will limit inherent carryover mixing of fresh and exhaust air due to rotor rotation to a negligible less than 0.5%.
The heat exchange matrix shall be assembled to give smooth parallel air passages of no greater than 10cm in depth for minimum pressure drop and maximum heat transfer.
The Rotors shall be mounted on sealed self aligning ball bearings of ample capacity externally mounted for easy maintenance.
The Heat Exchangers shall minimise leakage flows between fresh and exhaust air sides by means of replaceable rubbing seal on the rotor.
THE HEAT EXCHANGER SHALL HAVE A PROVEN SERVICE LIFE GREATER THAN 20 YEARS EVEN IN CHLORINATED POOL AND COASTAL SALT AIR ENVIRONMENTS WITH NO DETERIORATION IN PERFORMANCE.
THE MATRIX OF THE ROTOR SHALL BE WARRANTIED FROM DETERIORATION, CORROSION OR ERROSON FOR A PERIOD OF 10 YEARS WITH NO DROP IN THERMAL PERFORMANCE AND ENERGY SAVINGS.
All stated flow condition (equal fresh and exhaust air flows) as the unbalanced flow efficiency will be artificially higher and give a misleading understanding of the performance of the heat exchanger. A statement such as "efficiency must be greater than 80%" in isolation becomes meaningless.
This is a fundamental property of all heat exchangers irrespective of type. For more detail see the discussion in the Technical Aspects section.