A heat pipe is a sealed self-contained, liquid evaporating condensing system, usually shaped like a cylinder. Heat is transferred from the hot incoming gas to the evaporator section of the heat pipe. The local vapour pressure increases and evaporated fluid flows along the pipe to the condenser section. The vapour pressure is lower here, so the liquid condenses and the heat is released to the cold gas. The liquid then returns to the evaporator by a combination of capillary action and gravity.

Passive Operation

No energy input is required to operate the Heat Pipes. When two air streams pass through the Heat Pipes, (one air stream at one end, and another air stream at the other end), the temperature difference between the two air streams activates the Heat Pipes and causes them to exchange heat by “Heat Pipe action”. Heat Pipe action is a much more powerful heat transfer mechanism than convection flow. Heat Pipe action utilizes the heat capacity available when the working fluid changes phases, from a liquid to a vapor and back again.

Long Life

There is nothing in the Heat Pipes to wear out! The Heat Pipes are passive. They have no moving parts (unless they come equipped with a bypass damper.) To guard against corrosion, the Heat Pipes can be ordered with a baked epoxy coating or other protective coating. The Heat Pipes are fabricated with a multitude of charged circuits. Under normal operations, there is no reason for these ever to leak. If some inadvertent mechanical damage were to occur on one circuit to cause it to leak, there would be little effect on performance even if the leak was not repaired. Furthermore, because the tubes in Heat Pipe Technology Heat Pipes are copper, leaks can be fixed. Most other Heat Recovery Heat Pipes are fabricated with aluminum tubes which are very difficult to repair.

Isolated Air Streams

Dividing plates to separate the two air streams are an integral part of Heat Pipe Technology Heat Recovery Heat Pipes. The copper tubes carrying the Heat Pipe working fluid are expanded into the mating holes in the dividing plates, assuring an excellent seal to prevent cross contamination.

Minimum Maintenance

Since the Heat Pipes have no moving parts (apart from any dampers), the only maintenance recommended is periodic cleaning. A coil cleaner may be applied for this purpose just as for any cooling coil.

Minimum Size

Heat Recovery Heat Pipes from Heat Pipe Technology take up much less space than other heat recovery schemes. They are also generally considerably thinner than other heat pipes. A six-row Heat Recovery Heat Pipe can be fabricated with a thickness of as little as 7 inches.

Summer and Winter

The same Heat Pipe can be used for both summer cooling and winter heat recovery without any changeover mechanism. The temperature difference between the air streams activates the energy recovery.