Imperial Adjustable Thermostatic Fan Control

I have used several different thermostatic switches, usually non-adjustable for ease of install, and this is the first one that has proven reliable. Being adjustable, this one is slightly more complex to install, but it's well worth it. Just a tip: To make your install that much safer, use the switch to toggle your relay's GROUND, rather than positive pole. That means of the 2 connections to the switch, one is simply a very short wire to your mounting point, and the other simply hooks to the relay ground. Easy and reliable. Anytime you can take the positive connection out of a switch, it just makes it that much safer/durable. The only thing I don't like is that the "knob" to adjust the switch has no true "knob". I found that the volume knob off an old CB worked, but it really should come with the switch, as not everyone has junk automotive electronics laying around to scavenge from. For the most accurate reading of temps in the engine, and therefore most consistent operation, install the probe on the radiator in a spot nearest to the INLET. The inlet is the hottest part of the radiator, and accurately represents the temperature of the water in the engine. The further from the inlet, the cooler the water will get as the radiator does it's job and radiates heat from the water. If you cannot put the probe anywhere near the inlet, don't worry, because you control the operational setting, and can adjust for this. It just won't be as consistent as it could be by operating at the hottest location. Don't turn the unit on before your thermostat opens, as that is just wasted effort, which equals reduced power and economy. The engine won't cool until the water is actually flowing, after the thermostat opens. This unit can be wired to control a fan and/or an electric water pump. Using your imagination, could control other electric devices as well.

It was easy to install