Dehumidifier Specifications

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Dehumidifier Specifications

  • Service Vestibule
  • Microprocessor Control
  • Refrigerant Pressure Transducers
  • Refrigerant System Charges
  • Receiver Refrigerant Level Indicators
  • Direct Drive Plenum Fans with Variable Frequency Drives
  • Coated Airside Coils
  • Warranty
  • Commissioning
  • First Year Labor

Dehumidifier Specifications Bookmark and Share

In order to ensure the system performs reliably and that the equipment is suitable for an indoor pool environment, there are several items to look for in a quality product. The materials and components used must have adequate corrosion protection. Seresco uses only the best available materials, coatings and paints to ensure the longest possible unit lifespan. For example, the sheet metal used has an automotive grade galvanizing that is intended to withstand road salt. This already corrosion resistant sheet metal is then given a mill applied zinc phosphate primer followed by an exterior grade silicone modified polyester top coat.

Service Vestibule

The best way to protect a component from corrosion is to keep it away from the chlorine. All vital components in a Seresco unit are located out of process airstream, housed in a protective service vestibule. These key components include compressors, receivers, pool water heaters, contactors, control valves and electronics. Components in the airstream are kept to an absolute minimum, ensuring very few opportunities for corrosion.

There is an added benefit to using a service vestibule – 100% of the evaporator’s sensible cooling is delivered to the space for cooling. Systems with compressors, receivers and pool water heaters in the process air stream add so much heat that their unit cooling output needs to be de-rated by as much as 25!

Microprocessor Control

The dehumidification system controls the entire Natatorium environment. There are many aspects to this control, and feedback regarding system operation is vital to the building operator. Seresco’s CommandCenter microprocessor controller has full range of unit mounted sensors, pressure transducers and remote sensors that can all be accessed from the Keypad, building management system interface or over the internet using Seresco’s WebSentry web browser. All necessary information regarding the conditions in the space and system operation are always at the fingertips of the operator.


Factory monitoring of your system and dehumidifier 24/7 for no charge! With WebSentry all necessary information regarding unit operation can be viewed from a remote computer. Setpoints can be adjusted, sensors can be recalibrated, and unit performance can be monitored. Run a Cat 5 ethernet cable to the unit and plug it in.

There is also a Smartphone application for WebSentry!

Alarm at the unit? It’ll email you! Unit alarms will generate e-mails to any email address that you add to the contact list! Installing contractors and contractors trying to secure service contracts can be set up to access their units. The facility owner, especially those in remote locations will have a much more affordable means of ensuring their units are monitored and service is supervised over the internet by factory technicians.

Factory certified service companies can now offer pool operators 24-hour monitoring.

Internet Monitoring and Software Updates
WebSentry - Internet Monitoring and Software Updates
This is the new standard in customer satisfaction and unit reliability.

Refrigerant Pressure Transducers

Unit mounted pressure transducers allow the operator or serviceman to access the vital refrigerant pressures through the operator panel of the microprocessor (or remotely via the internet) rather than having to connect a set of refrigerant manifold gauges. This is the most important operation and diagnostic information for any refrigeration system and the ability to access this information at any time is a significant benefit. Systems without refrigerant pressure transducers require a service technician to visit and connect gauges anytime information regarding the refrigeration circuit is desired.

The refrigeration pressure information from these transducers is used in the control of the Seresco unit. Seresco is the only company in the industry that uses real time refrigeration pressure information in their control sequence. The result is a significantly more reliable unit.

Refrigerant System Charges

Seresco offers systems with R410A and R407C refrigerants. These blended refrigerants are expensive and there are steps the designer can take today to ensure the owners refrigerant costs in the future are minimized:

  • Specify the maximum total allowable system charge.
  • Keep outdoor air-cooled condensers as close to the dehumidifier as possible.
  • Water-cooled or closed circuit fluid cooler unit configurations have the smallest charges. These units come with a complete factory charge and require no onsite refrigeration piping or charging.

Seresco’s Protocol™ Design uses 75% less refrigerant compared to a traditional split system.

Receiver Refrigerant Level Indicators

Sight glasses mounted on the receiver allow for easy refrigerant charge adjustment without the expense of evacuation and weigh-in techniques. Seresco is the only manufacturer to use this time and money savings feature.

Direct Drive Plenum Fans with Variable Frequency Drives

Direct drive plenum fans with VFD offer the most efficient means of moving air while using the lowest possible fan energy. Belt driven systems are a service and maintenance concern and are an inefficiency that consumes more energy. VFDs allow for easy supply air balancing without changing pulleys or belts.

Coated Airside Coils

All coils exposed to the pool air must be corrosion protected. Seresco fully dips all coils to ensure 100% of the coil is protected from corrosion with the best coatings available in the industry.


Five (5) year extended parts only warranties on compressors and airside heat exchangers are generally a good investment. 10-year coils warranties are also available but can be costly.


The final performance review of a dehumidifier can only be completed once the natatorium is operating at design conditions. Often the initial startup is done with a cold pool. These facilities require a follow up visit once the water has reached design conditions. Specify that a factory trained/certified service company perform the startup and commissioning. This may not be the installing contractor.

First Year Labor

If the installing contractor is not doing the unit start up, specify who should be responsible for the first year labor warranty.