Can You Install a Dehumidifier on HVAC Rooftop Unit?

Uses

• Dehumidifier units used in conjunction with a rooftop HVAC unit are typically installed on buildings such as schools, apartment buildings, churches, restaurants and grocery stores where it is beneficial to have them out of sight and out of the way. Many of these buildings experience rapid fluctuations in humidity and might need a dehumidifier to keep humidity levels constant. In particularly humid climates where temperature drops are common, dehumidifiers can be used to maintain existing humidity levels.

Rationale

• The rationale for installing a dehumidifier as part of an HVAC unit installed on a roof is that roof units are sometimes forced to sacrifice cooling capacity for the sake of dehumidification. Moisture control valves are the primary means by which humidity is removed from most rooftop HVAC units, but these valves have a limited capacity and effectiveness, especially when both maximum cooling and moisture removal are needed at the same time. A dehumidification unit can help to maximize moisture removal when it is needed most.

Benefits

• Several benefits exist to having a dehumidifier installed as part of an HVAC unit on a rooftop. For instance, these units are designed to prevent over-heating and over-cooling by controlling the humidity closely within the building. This helps to reduce compressor cycling which, in turn, increases energy efficiency of the existing HVAC unit. Compressor cycling can cause voltage spikes and increases the potential for power surges and other electrical problems.

Units

• Dehumidification units come in a variety of styles and brands, and can help meet the needs of building owners who need to control the internal environment of their establishment. While each major brand offers a variety of features, control features are among the most important. Building owners and managers in charge of businesses or other establishments where these units are used need to be able to have control over the system in order to make any necessary adjustments. Some brands offer both "whole system" control and "spot" operation as an option. This allows the user to apply dehumidification settings to the entire building or only to particular rooms withing the building.