I am going to install the model 700 Aprilaire humidifier unit. I’m tight with space on the supply duct. Will I lose any capacity or performance if I place it on the return duct?
Thank you for your email regarding your model 700M Aprilaire Humidifier. The model 700M may be installed on the cold air return duct, however it requires a hot water supply. This is because the humidifier requires heat for evaporation and hot water is the only heat source available when it is installed on the cold air return. The performance will be very similar to how it performs on the warm air supply with cold water.
Please be aware if the humidifier is not professionally installed our 5 year warranty on parts is void.
Thank you for giving us the opportunity to be of service