Temperature controller for canopy fans

[Hightower]

Has anyone tried using a computer fan controller with the temperature sensors on them and mod it to accomadate a couple canopy fans that would come on when the water temperature rises?

In theory it should work quite well. There just has to be a way of isolating the regular sensors from the saltwater.

a 12VDC adapter should be easy enough to find to power the unit.

Otherwise any other suggestions you have tried that work and are easy and inexpensive?

Right now my water temperature rises 3deg during the day if I dont turn on the canopy fans, but then the heater will also come on which of course is bad energy management.

[TRS]

I have two 4-inch fans in my 72-inch canopy (with 3 X 250W MH and 2 X VHO FL bulbs). Since the VHO FL are plugged into an ICECAP 660 and a Solar 1000 dimmer, the VHO FL do not burn at full intensity so they are not a big power consumer and do not burn that warm. The fans are plugged into the same timer as my MH lights so they power up together. With these fans on during the day, my water has climbed to ~84 degrees. I also use an external fan that I wired up to blow across the surface of my tank. It really helps with the cooling, but also adds to the evaporation. The good news is that my temperature does not exceed 80 degrees during the day. It might be poor power management too, but it beats the crap out of buying a chiller and paying for its power consumption too. HTH

[BMW Rider]

I'm using an HVAC thermostat as a controller. It is a Noma brand digital non-programmable unit with an AC mode. I picked it up for $20 at Canadian Tire. I de-soldered the temperature sensor from the circuit board and reconnected it with a length of wire. I then sealed the sensor inside a glass tube from a used up test kit with silicone. The thermostat uses two AA batteries to operate and switches the fans on and off as needed. I'm using two 12v computer fans powered by a transformer.

[mark]

Got a datalogger (PLC) was going to get all fancy with the program, probes and relays but thought until I do, just have the fans come on at the same time as the lights.

Plugged the lights and fan into the same power bar and that into a single timer, adjusting the heater, temperature now steady at 78°.

Now can evaporate over a gal/day with the fans blowing on the water, but at least the temps okay.

[Hightower]

Thanks for the suggestions.

[KarlK]

see, someone else used the HVAC t-stat!!