Energy Recovery Ventilator (ERV) is an important aspect of your heating and cooling as it efficiently helps improve your indoor air quality. It allows fresh air to enter your indoor space while maintaining the needed air produced by your HVAC system. It, therefore, reduces the load of your unit and saves you on your energy consumption.

How ERV Works

Basically, ERV features both air to air heat interchange and ventilation system combined. An ERV works through an air exchange in your system. Heat is transferred between incoming and outgoing airflows making it easier for your system to heat or cool the air to suffice your home’s needs. With ERV, the exchanges in temperatures between these two airstreams and the removal of stale air while holding the required temperature inside are possible.

Types of ERV

Wheel or the rotary heat exchanger. The wheel gathers heat from one air stream then transports it to the other. You can choose between a metal wheel which only transfers heat (sensible energy) or plastic wheels which transfer heat and can also absorb moisture (latent energy). Wheels are the most widely used ERV because they are affordable and can be easily maintained.

Plate heat exchanger or fixed core. Fixed core plates are more costly than wheels and they are typically used for hospitals and other large establishments. With this type of ERV, air flows through a series of channels. These channels are heated then the heat is transferred to the air flow inside. Metal plates transport only sensible energy, some plastic plates can absorb only sensible energy but some are sensible and latent combined, while all paper plates absorb both.

Heat-pipe heat exchanger. This is a sensible only ERV. Heat pipes are made of copper tubes with refrigerants inside, running between flows of air. When the refrigerants are heated through the tube, they evaporate and the vapor flows to the other stream. When that stream cools the pipe, the refrigerants condense, causing the air flow to get warmer. The cooled refrigerants are then ready for another cycle.

Runaround coils. This type of ERV has commonalities with the heat pipes only that there are distances between the exhaust and the outdoor air streams. Water connections are built in the exhaust airflows and the ventilation airflows. Just like heat pipes, this can only transfer sensible energy.

ERV is a great way to cut your expenses in half. Contact Walker Heating and Cooling for ERV installation suggestions and other HVAC services.