Most molded products, whether injection molded, blow molded or vacuum formed (thermoformed) products are cooled by chilled water in mold cavities. The cooling time, which normally is the longest part of the total cycle time and the molding process, is an expensive and an important part of the manufacturing process. Lowering the chilled water temperature in the mold leads to a shorter cycle time.

It is suggested to use pure chilled water at a temperature not lower than 6 °C [43 °F]. Lower water temperatures require adding antifreeze to the water in the cooling circuit to avoid freezing in the heat exchanger (evaporator) of the chiller. Adding antifreeze to the chilled water to achieve a low temperature has its disadvantages. Antifreeze agents normally have low thermal conductivity which lowers the heat withdrawal from the product in the mold and the majority of them have high viscosity which lowers the water pump performance and reduces the water flow rates. The chilled water flow rates are recommended to be at a high rate to create turbulent water flow in the mold cooling channels.

Experiments on blow molded products showed a production increase of 1% when the chilled water temperature was lowered 1 K [1.8 °F]. This fact was consistent until Glycol had to be added to the chilled water to avoid freezing in the heat exchanger of the water chiller. The water/Glycol mixture had to be cooled down to a temperature of -14 °C [7 °F] to get the same cycle time with pure water at 6 °C (43 °F) on a light weight product. The same product but 50% heavier needed a water / Glycol temperature of -20 °C [-4° F] to achieve the same cycle time as with pure water at a temperature of 6 °C [43 °F]. A similar experience was made in other molding processes.

Lowering the temperature under the dew point of the ambient air causes condensation on the mold surfaces adding challenges to the process.

In many manufacturing plants process engineers tend to increase the chilled water temperature in hot and humid climates to avoid mold sweat and this leads to some problems. Increasing the chilled water temperature extends the cooling time, slows the production and shrinks the profit. In many cases a longer cooling time increases the crystallization rates in the molded plastic resulting in inferior product quality.

Some manufacturing engineers assume that air conditioning systems can solve the mold sweat problem. Air conditioning the manufacturing plant helps, but it does not completely solve the problem. One disadvantage is the high initial investment required to install a sufficient air conditioning system and the huge operating cost of the system, which becomes obvious when considering the energy household of a plastic processing plant. The total energy supplied to the plant is converted into heat. Some of the heat is transferred out of the plant through the mold water cooling system and other water cooling systems such as hydraulic fluid cooling. The remaining energy is transferred into heat in the air. The air conditioning system has to be capable of handling the heat radiated in the plant and the dehumidification of the air inside the manufacturing plant. Air conditioning systems may improve the working environments for the working force in the plant but the high operating cost shrinks the profit.

Another disadvantage is that the humidity is not absolutely controlled in an air conditioned plant. Ambient air mixes with the air in the plant whenever a gate or a door is opened. Moisture penetrates through the concrete floors and the walls of the plant, if the building is not designed with a sufficient moisture barrier. Exchanging molds in processing machines is accompanied by water leaks. Cleaning and washing the floors also results in additional moisture in the plant air.

The ideal and most profitable solution is the Mold Area Protector (MAP). This should be combined with a good ventilation system in the plant to get rid of the excessive heat radiated from the machines in the plant.

The MAP is a simple air dehumidification unit with integrated chiller (condensation dryer). It filters the ambient air sucked into the unit through a washable and replaceable filter and then chills the air to a temperature of 3 °C [37 °F] in two steps before the air is being heated to a temperature of 25 °C [77 °F]. The first chilling step requires chilled water from the plant's chiller at the same temperature used in mold cooling. The second chilling step is done by the integrated chiller of the MAP unit. A lot of the moisture contained in the air is separated from the air due to condensation on the cold surfaces of the heat exchangers (pre-cooler and evaporator). The heat extracted from the air in the second chilling step is given back to the air after it has lost the moisture in the condenser of the chiller. A blower sucks the air through the unit and blows it in a duct work to the molding areas to be protected from sweating.

The mold area protection is a complete system in which the clamp and mold area of every machine is enshrouded and separated from the ambient air. Trained installation technicians install the custom made covers on the machines and connect the dry air duct work to every machine.