High pressure vane type recirculating pump to compensate for long hose runs resulting in high pressure drops
Hermetically sealed compressor
Environmentally safe R-134A refrigerant
Digital temperature controller
Submersed copper coil heat exchanger for high efficiency and dependability
Casters on all models
All wetted surfaces utilize non-ferrous materials to reduce scale and rust
Rugged stainless steel reservoir and cabinet for durability
Outdoor Chiller Considerations
NOTE: Chillers designed for indoor applications should NOT be used outdoors. Only chillers designed for outdoor use will be durable and reliable enough to endure the rigors of the environment. For roof mounted installations, please contact a building architect to verify that the roof structure is capable of supporting a fully charged/filled chiller.
Chiller should be located as near as possible to the equipment being cooled.
Direct sunlight on the condensing coil can severely reduce operating efficiency. A shaded location on the north or east side of a building is most desirable.
If the chiller has a horizontal discharge, do not face the discharge into the prevailing wind. Service access and the air inlet should be located a minimum of 3 feet (1 meter) from walls and other obstructions.
Do not install the chiller in an enclosed shelter unless proper intake and exhaust venting is provided. Do not allow canopies or roofs on open-sided shelters to restrict the air flow on chillers with vertical air discharge. Allow a minimum of 8 feet clearance. Also, be aware of the potential to restrict air flow caused by downdrafts and eddy currents that are created by surrounding structures.
If the chiller will be located near a residential area or potential for vandalism exists, a security fence with a lockable gate should be erected around the chiller.
The chiller should be set on a concrete slab. The slab should extend a minimum of 12 inches (30 cm) beyond the perimeter of the chiller to prevent damage from lawn maintenance equipment, etc. The chiller should be level and properly anchored.
4. FLUID LINES
As the distance from the chiller to the equipment being cooled increases, the pressure drop in the supply and return fluid lines for a given line size and pressure will increase. In order to minimize pressure drop, refer to a friction loss chart for various pipe sizes to determine the proper piping diameter for the given distance.
5. AMBIENT TEMPERATURE
When outdoor ambient temperatures will be above 95 degrees F. (35 degrees C.) or below 50 degrees F. (10 degrees C.), the chiller manufacturer should be consulted. High ambient temperatures reduce chiller capacity. Low ambient temperatures require special controls. Special conditions apply when temperatures drop below 32 degrees F. (0 degrees C.). Fluid heaters may be required to prevent freezing and to hold the fluid in the chiller reservoir at a constant temperature in order to reduce start-up delays while the fluid warms up to operating temperature.
A remote indoor electrical panel that displays chiller status and houses the temperature controller and on/off switch is recommended.
The chiller reservoir should be filled to the proper level with an inhibited glycol designed for HVAC/R systems. Do not use automotive antifreeze. The inhibitors used in automotive antifreeze can break down quickly and accelerate the degradation of the coolant base (glycol); as well as promote corrosion in a system. Silicates used in automotive antifreeze coat heat exchangers, resulting in reduced heat transfer. Also, silicates can gel causing fouling and plugging of a system.
The ratio of inhibited glycol to water should be adequate to prevent freezing at the lowest ambient temperature. Check the level with all lines filled. The glycol mixture should be checked periodically (3 to 6 months) for proper concentrations. When filling the system, always use a pre-mixed solution in the proper ratio to maintain freeze and corrosion protection. Distilled or deionized water is recommended because many municipal water supplies contain large amounts of chlorine, which can react unfavorably with glycol.
NOTE: If supply and return lines are overhead, the fluid in the piping may drain back and overflow the chiller reservoir if the chiller is shut down. This can be prevented by using a check valve in the supply line, and either an inverted trap with a vacuum breaker or a solenoid valve on the return line.
Dimplex Thermal Solutions has the broadest line of Chillers in the Industry. With Designs for the Plastics, Machine Tool, Medical, Food and Pharmaceutical markets and being one of the largest suppliers of Chillers in the world gives Dimplex a competitive edge that is unbeatable in the chiller industry.