AirScape Whole House Fan

Introduction

This article is dedicated to controlling an AirScape whole house fan like the 1.7, 2.5e, 3.5e, 4.4e or 5.0e with an ISY. When connected to your network, these fans can be controlled from a browser and even better, a network resource. With clever programming, you can turn off your a/c when it is turned on, suggest using the fan based on inside and outside temperature, create a more powerful timer, use buttons on any keypad to control the speed and timer, and turn off the fan if it gets too cold inside.

Control of the fan via keypad is done with 2 buttons, one dedicated to speed and one to the timer. For both speed and the timer, a normal press increases, a double press decreases and a long press turns the fan off.

TODO

• Automatically start the house fan if the outside and inside temperatures are right, a suggestion has been sent and some windows have been opened.
• Disable the house fan if the outside temperature is very low.

State Variables

sHouseFanSpeed 0 0
sSuggestHouseFan 1 1

sHouseFanSpeed holds the current speed of the fan for use in programs. sSuggestHouseFan is used by the suggest program to minimize the frequency of suggestions.

Integer Variables

iHouseFanTimer 0 0
iHouseFanTimerIncriments 30 30
iHouseFanTooCold 68 68

iHouseFanTimer is used for the fan timer maintained by the ISY (instead of using the fan's built in timer). iHouseFanTimerIncriments controls how many minutes it increments or decrements on button pushes, I feel 30 minutes is a nice number, but maybe you'd prefer 60. iHouseFanTooCold is used to shutdown the fan if the temperature inside gets too low, 68 is pretty cold.

= Network Resources

WHF speed up http://whf:80/fanspd.cgi?dir=1
WHF speed down http://whf:80/fanspd.cgi?dir=3
WHF off http://whf:80/fanspd.cgi?dir=4
WHF add hour http://whf:80/fanspd.cgi?dir=2

These are all self explanatory, but WHF speed up increases the speed, WHF speed down decreases it, WHF off turns it off and WHF add hour adds an hour to it's built in time. I don't use the built in timer because it has no way to configure the increments nor can you decrease the timer. Of note is that you can only increase or decrease the speed, you can't just pick the speed you want. If you want the highest speed, you have to WHF speed up five times.