Chilled Mirror Hygrometers in HVAC testing

Modern air conditioning and climate control systems are used in a wide range of environmental conditions across the world. The primary purpose of these systems is to maintain thermal comfort by regulating indoor air temperature and humidity. To maintain air quality, fresh outside air is continuously drawn into the HVAC system and conditioned before being circulated indoors. However, due to varying local climates, outside temperatures could be anywhere between -50 & +50°C, with humidity levels between -30 and +30°C dew point.

Designing a system with satisfactory performance across such a wide range of conditions is a challenge, therefore HVAC systems need to be properly set up, and subject to a rigorous testing regime before sale. The purpose of this testing is not only to evaluate the performance of the systems temperature and humidity control, but to ensure the system is energy efficient, filled with the correct level of refrigerants and is not subject to any leaks or problems with drainage.

HVAC System Testing

To ensure product quality; each system is tested in a variety of environmental conditions to ensure that the following parameters are within acceptable limits at the outlet:

  • Air flow
  • Temperature
  • Pressure
  • Humidity
  • The purposes of the tests are to validate the performance and efficiency of the system, and to determine the required fill level of refrigerant gas. Each manufacturer will operate multiple test rigs, which consist of a pair of environmentally controlled chambers: one to simulate conditions outdoors, and another to simulate conditions indoors.

    Why is humidity measurement of HVAC important?

    Accuracy of dew point measurement at the inlet and outlet of the unit under test is crucial, as the closer to the true value the measurement is; the more precisely the refrigerant fill level of the condenser can be calculated.