I see a lot of folks who buy the A/C Infinity T- series line of fans. I did the same thing! The problem is you cannot set the off speed except for off. The fan either runs at your pre-set speed or its off!!! These units are advertised as “growroom fans” but are really just attic fans to exhaust excess heat or humidity. However, the S- series duct fans which have an optional controller 67 for $49.00, gives the grower a means to have preset minimum speeds. So you can have your fan running at whatever speed you want to maintain fresh air intake. I run at 1-3 speed usually. Then set my high temp and high humidity to 84degrees and 55% humidity, with the fan speed set to 6. When the temperature hits 85 deg, the fan will rev up to the alarm preset speed. In this example we use 6. After the temp drops below 85deg, the fan will revert back to the off setting, which is set to 3. Same will happen with the humidity. This is true temp and humidity control for a tent grower. Idk if you can replace a T-6 controller with a controller 67. When I found out the T line sucks for growtents, I called
AC Infinity, and they told me about the S series with controller 67, and recommended me to send back the more expensive, T-6 series fan and they would replace it with the S-6 fan and controller 67. Cost $109.00 fan $49.00 controller! Happy happy happy!!