These dampers act as a block at the main duct trunk line, causing your system to function like there isn’t a vent in that particular room at all. Unless you’re experienced working with HVAC ...

Catalyst costs are excluded. •Ammonia Injection: The ammonia unloading, storage, and supply system includes a storage vessel with a seven-day capacity, an ammonia vaporizer, mixer, injection grid, ...

If the damper is damaged, warped or stuck ... pro if you think you have an electrical issue or need fixes within the ductwork, since damaging the ductwork can add to the cost and complexity ...