Take a Video Tour
    of The Hope Group

  View Video Archive

Our Best Advice

Customers rely on us to help select components, design complex systems, to manufacture, install, and maintain machinery and equipment. We offer our best advice through our blogs.

The Hope Group

The Hope Group is an authorized full-line Parker distributor featuring hydraulic, pneumatic, fluid connector, and sealing products for OEM and MRO applications.

Sorensen Systems is a designer/builder of custom systems providing clean water, renewable energy sources, and technologically advanced process systems for industry.

Hope Air Systems is an authorized distributor for Kaeser Compressor featuring energy efficient rotary screw compressors as well as a designer/builder of skid-mounted packaged compressed air systems.

Hope Service can dispatch its field service fleet of vehicles and experienced, factory-trained technicians to provide emergency and routine field service to its hydraulic, electrical, and compressed air systems customers.

The Hope Group owns and operates eight Parker Stores at its branch locations providing "while you wait" replacement of hose assemblies and immediate on-hand access to 3,000 Parker fluid connector parts.

The Hope Group provides 24 hour access to $150 million of Parker parts through its eCommerce website,, offering one or two-day shipping of all your hose & fittings, hydraulic, pneumatic, valve, and filtration needs.

iPower Distribution Group of New England provides supply chain consulting and implementation through streamlined procure-to-pay process, vendor managed inventory (VMI), Kanban, and in-plant buyer-planner services.


Hope Air Systems Home › Buy From Us › Compressed Air Dryers › Cycling Refrigerated Air Dryers
Our Best Advice

Peter Rhoten   10 Worst Things You Can Do To Your Air Compressor
Peter Rhoten
Hope Air Systems

Ray-McCann   Monitoring Operational Conditions In The Palm Of Your Hand
Ray McCann
Fluid Power Specialist

mike-gardella   Sorensen Systems Designs Aerospace Fluid Control Test Stand
Mike Gardella
VP Engineering & Mfg

Donna-Tibbetts   One of Our Stores is Open 24 Hours a Day!
Donna Tibbetts
Operations & Service Mgr

doug-markham-ipower-new-england   When Should Materials be Stocked at Point of Use?
Doug Markham
President, iPower NE


Cycling Refrigerated Air Dryers

Hope Air Systems distributes compressed air dryers manufactured by Kaeser and other manufacturers designed to meet the critical operational specifications for its industrial customers. Among the most popular types of dryers are "refrigerated" dryers. They are available as cycling or non-cycling, each with particular advantages.

The Kaeser "Secotec" model of cycling refrigerated air dryers, available from 20 – 520 cfm @ 100 psig, provides maximum efficiency by operating the refrigerant compressor only when necessary. This is achieved by utilizing a thermal storage medium. The refrigerant system cools the medium to a certain temperature, cuts off, and then stands by until the temperature rises to a predetermined level before switching on again. In this way, the dryer is not wasting energy when the demand is low. A non-cycling dryer would continue to operate even during low demand periods.

Why do we need dry air?

As atmospheric air is drawn into a compressor, water vapor is introduced as well. During compression, air heats up and is able to hold more water vapor. Mechanical separators and filters are used to remove liquid water, yet air remains saturated with water vapor. As air travels through the piping, the vapor cools, condenses and may pass into production tools and equipment. Using a refrigerated dryer eliminates vapor before it condenses and affects the system.

Operations characteristics of cycling air dryers

Warm compressed air entering the dryer is initially cooled in the air-to-air heat exchanges by the cold compressed air leaving the dryer. This allows for greater efficiency by reducing the heat load on the refrigeration system. The air is cooled to the dew point temperature in the lower part of the heat exchanger by a refrigerant circuit with a thermal storage medium. The condensate formed by the cooling action is separated from the compressed air by a multi-stage, stainless steel, maintenance-free separating system. The automatic condensate drain drains the water without wasting valuable compressed air. The dried air leaving the dryer is reheated in the upper part of the heat exchanger before exiting the outlet. Reheating the compressed air eliminates pipe sweating downstream.

Energy savings advantage

The cycling control of the Secotec design provides the greatest savings during low demand periods, such as, evening and night shifts. The chart shows significant savings are possible on a daily basis. During breaks, low demand periods, and shut down, the dryer saves energy because the refrigerant system has shut off.

Energy savings specifics

Let's look at a hypothetical situation to understand potential energy savings. If a 240 cfm non-cycling dryer operated 24 hours a day, 365 days a year (never shutting off) it would operate over 8,000 hours. Using estimated costs for electricity (for comparison) the costs would look like this:

8,000 x 1.5kW x $0.08/kWh = $ 992

If the cycling dryer only runs when needed, which would be about 1,000 hours, instead of 8,000 hours, the costs would look like this:

1,000 x 1.5kW x $0.08/kWh = $ 120.

That's a savings of 88 percent or about $ 872 compared to $ 992. That's a lot of savings.

Important features and advantages

All components in the Kaeser Secotec dryer such as heat exchangers, refrigerant circuit, condensate separator and drain are conveniently accessible from above when the panels are removed. Service connections are provided at the suction and discharge lines to check the refrigerant circuit. The dryer construction and component arrangement minimize the required floor space. Among the important features are:

  • efficient cycling control
  • high thermal storage capacity
  • minimal pressure drop
  • no prefilter required
  • stainless steel condensate separator
  • no-loss electronic condensate drain
  • quick access to components
  • durable control cabinet
  • easy to read control panel



Kaeser Secotec Dryer
The Kaeser Secotec Dryer is available from 20 to 520 cfm @ 100 psig to provide maximum efficiency by operating the refrigerant compressor only when necessary. The refrigerant system cools the medium to a certain temperature, cuts off, and then stands by until the temperature rises to a predetermined level before switching on again.


The Hope Group, a division of KLX Inc. | 70 Bearfoot Road, Northborough, MA 01532

Phone: 508-393-7660 | Fax: 508-393-8203 | Email

Conditions of SaleLegal DisclaimerJobsOur Mission

© 2018, The Hope Group. All rights reserved