The air in this broiler house was not wel circulated. As a result the warmth and the oxygen was in the upper part of the house while there was a high CO2 concentration on the ground level. Mutlheat modified the Multiheat water heating system to improve the air circulation. This unit does not have the heat exchanger module. Instead the ventilation is used to recirculate the air from the roof by blowing it into the broiler house. As a result there is a 20% energy reduction and the humidity in the broiler house has significantly reduced. The piping was made in a modulair way to make it easy to be cleaned.