The Plus-Touch is a great replacement for the Norsol DVS-25HA. It has two stages of variable speed fans, as well as the option to add four stages of 0-10VDC for VFD controlled fans, or other 0-10VDC equipment. It also has six relays (stages), all of which can be interchangeably configured for fans, heaters, actuators/inlets, mister/foggers, or timed events.

Norsol specs: 

The DVS-25HA has: Two stages of variable speed fans that can be connected to the controller, as well as three stages of constant-speed fans and two stages of either constant-speed fans or heating units. In addition, one of the constant-speed fan stages can be configured as a mist cooling stage.