Standard test conditions for water-from-air machines

Users of water-from-air systems are interested first usually in two pieces of information;

• Water production rate or dehumidification capacity [litres/second, litres/minute, litres/hour, litres/day, pints/24 hours, gallons per hour, gallons per day, etc.]
• Energy consumption per unit volume of product water [kWh/L, kWh/gallon, etc.] or Energy Factor [L/kWh]

How do you compare the water production rate and energy consumption claims made by the various manufacturers of water-from-air machines?

Comparison is made easier by manufacturers giving machine specifications for standard test conditions. Many manufacturers use this standard:

Association of Home Appliance Manufacturers: Dehumidifiers, AHAM DH-1-2008.

This standard (available for purchase from AHAM for $25 at this link) is referenced by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. (ASHRAE; http://www,ashrae.org) in the 2008 ASHRAE Handbook, Heating, Ventilating, and Air-Conditioning Systems and Equipment, Chapter 24, Mechanical Dehumidifiers and Related Components.

At standard test conditions, the air entering the dehumidifier (water-from-air machine) must have:

• Dry-bulb temperature = 80°F (26.7°C)
• Wet-bulb temperature = 69.6°F (20.9°C)

Stated another way, standard test conditions are 80°F (26.7°C) and 60% relative humidity.

AHAM DH-1 provides details on instrumentation, test procedures, nameplate data, capacity test and energy consumption test, performance tests, and safety.