Frequently asked questions (FAQ) (en)

Heat exchangers transmit energy as warmth from one source (e.g. gas or fluid) to another. You can find heat exchangers in the industry, in vehicles and in houses, but also in refrigerators and boilers. Heat exchangers, that are specially designed to recover warmth from trash, exhaust fumes and fluids are known as recuperators. One of the producers of units for the air-to-air heat recovery installations is Recair in Waalwijk. These heat exchangers from Recair are the best performing units in their sort.

A heat exchanger ensures that the energy of polluted air leaving the room is transmitted to the fresh air that enters the room. During winters, you do not have to put as much extra heat in to create a comfortable temperature. With the heat exchangers that the heat exchanger webshop offers, more than 90% of the energy is transmitted to fresh air, which is through this, preheated before entering the house.

No, a heat exchanger is not a filter. Fresh air from outside enters the room through the heat exchanger and the polluted outside air leaves. The heat exchanger does not stop any particles. The heat exchanger ensures that the energy stays in the room. Oftentimes the thermostat does not even turn on as a result there of the central heating will be out more often.
Regularly, filters are included before and after the heat exchanger in the air-handling unit. These are separate parts, which stop soot, dust or smoke. Clean air is always entering the space.

In many new building houses an air-handling unit is mounted, which ensures that the air within the building is constantly refreshed. Part of the air-handling unit is the heat exchanger. After a while the heat exchanger gets polluted. The panels get a layer, whereby the effectivity reduces. It takes several years before it comes to this point. For that reason we recommend you to replace the heat exchanger after 8 to 10 years.

Before you order a heat exchanger with us, you have exactly indicated what heat exchanger you need. Thereby you have checked the measurements of your heat exchanger. After receiving the request, the order is specially made for you. It concerns a tailor-made product and not a product in stock. For that reason you cannot return the product. But if you have precisely measured the dimensions, that will not be necessary.

It is very important to order the exact same heat exchanger as the old one. Otherwise the heat exchanger does not fit into your air-handling unit. Following the instructions during the order process is recommended. When you precisely measure the dimensions, nothing can go wrong.

After placing the order, we need approximately 10 days before receiving your new heat exchanger. We need this time for production (custom made products specially for you) and shipment. If you live outside of The Netherlands shipping may take a few days more.

Heat exchangers transmit energy as warmth. That warmth is transmitted from one medium (air, gas or fluid) to another. Heat exchangers, whereby a complete separation between two mediums and whereby no intermediate storage of warmth takes place, are called recuperators.

Heat transmission
In an air-to-air recuperative heat exchanger, the incoming and outgoing airflows are separated by a solid barrier (i.e, a duct wall). Providing that there is a difference in temperature between the two airflows, heat from the warmer airflow will be transferred through the barrier to the cooler airflow in accordance with the second law of thermodynamics. This states that heat will move from a hotter region to a colder region. In this way, the heat from the warm, stale air leaving the building is transferred to the cool, fresh air entering the building or vice versa.

Minimum heat temperature
For equal distribution of incoming and outgoing airflows within the heat exchanger, the walls need to be formed with channels all of them having the same resistance. The use of heat exchangers within a ventilation system no draft is experienced. This is because the incoming airflows have almost the same temperature as the air that is already in the room.

If a heat exchanger performs as promised there will be no question of warm or cold draught. The incoming air will be about the same temperature as the room and therefore also the outgoing air. If for example during the winter the incoming air is considerably colder than the temperature in your room, it probably has something to do with a not functioning heat exchanger.