View Full Version : Air Conditioning Energy Saver Switch

07-25-2008, 02:34 PM
I'm getting killed on my electric bills at my office. The 220V AC units are always being left on. Is their a device that I can install with a key that will stay locked in the cylinder in the on position (to activate the AC) and release in the off position. It will be the same key for the front door so that when people leave for the day, they will have to remove the key - AC goes off - in order to lock the front door???

Any help/ideas greatly appreciated

07-25-2008, 05:13 PM
Might be easier to sense the "door locked" state and turn off the AC, or "door unlocked" state and allow the thermostat to control it. Or, select one of two thermostats depending on the state of the door.

07-25-2008, 05:28 PM
Seems the easiest thing would be to plug the A/C into a timer

07-26-2008, 07:42 AM
Yes there are locks and electric key switches where you can't remove the key when on. See a locksmith about that.

So far a wiring it to your air conditioner, find an "old timer" who knows what he is doing and this could be installed. Might also need a "relay" installed.

As to sensing a locked door electrically, I think I read about door locks you can buy which have this built in. Ask a locksmith or search google.com

Or old timer security system employees (who know what they are doing) sometimes install devices in doors which sense the door or deadbolt is locked. For some security systems, they want to know if the door is locked or not.

Also if you get an electrician involved, might also be able to turn off the lights as well as the A/C.

Get the right people who know what they are doing and you can do whatever you want.

As to saving on A/C costs, there are things you can do to reduce your energy usage. Like painting the roof white, adding more insulation, installing double pane argon filled Energy Star windows, getting a new energy star air conditioner. Or possibly if just one person in office, installing a window air conditioner in that office and running just that instead of cooling the whole office.

More energy saving tips here...

07-26-2008, 08:03 AM
P.S. I once wired a switch in an office which was located next to the door. This switch turned off the water cooler, the door chime, and the phones.

So they would turn this switch off when leaving saving a bit of electricity (The business owners also turned off their lights and A/C as they were the ones receiving the bills...)

07-26-2008, 09:04 AM
Finding a switch that used the same keyway as your door might be a problem, but otherwise a simple key operated switch controlling the power to the thermostat is all you need. Key in and on--heat works, key off and out--unit is off.

07-26-2008, 12:03 PM
Having this automatic migh pose problems if the door was locked while people were working, when they were not open to the public...they wouldn't like it if the a/c couldn't run! Or say the boss comes in early or stays late, but locks up.

The contacts of a typical timer may not be able to handle the current directly or would be large, but it could easily control a relay or contactor that could. You could do the same with a low-voltage switch located near the door -- shut all of the switches off on the way out. You could do it with a 120vac relay, too, if you didn't want to deal with low-voltage, but you can string low-voltage wires easier than running a new 120-vac one.

07-26-2008, 03:37 PM
Contact a security company and have them install personnel sensors in appropriate places. Then if people are in the area, condition the space for "occupied". If not, for "unoccupied". You could also then detect and log occasions when people were there, and where they were, when they weren't supposed to be.

07-26-2008, 05:54 PM
Wouldnt it be easier to raise the rates a lil bit 25-30.00 per month can go a long way during the summer months.

07-26-2008, 06:38 PM
I am guessing that you also posted at http://www.diychatroom.com/showthread.php?t=24270 in which the best solution would be to either use a Setback Thermostat under a locking cover, or a Internet IP thermostat that can be controlled & watched remotely.

As for the bills, cost of utilities have gone up everywhere, and a lot of it, is that those that do not pay their bills, are causing the rest of us to pay more.

07-27-2008, 07:31 AM
that those that do not pay their bills, are causing the rest of us to pay more.

those that do not pay their bills do not need a switch control on their A/C units because they will not work, and neither will the lights.