FAQ - Frequently Asked Questions

#01 – What is the Window Sensor W1?
It is an advanced wireless sensor that turns off the air conditioner when a window or balcony door is opened. Until the window (or balcony door) is closed again, Window Sensor W1 will cut power to the air conditioner, preventing it from turning on. Once the window (or balcony door) is closed, power will again be supplied to the air conditioner, which will then be able to return to normal operation. This avoids wasting electricity and money by trying in vain to cool a room where warm air is coming in through an open window.

#02 – Why wireless?
For years, hotels have used wired solutions that cut the power supply to the indoor unit when the window is opened. But this type of solution is daunting for hoteliers, because wires have to be run from the air conditioner to the windows, with unsightly wiring or ducting in view, with increased installation costs. Window Sensor W1, with its wireless technology, solves these problems, and costs significantly less.

#03 – How far can the signal reach between the sensor and the receiver switch?
Window Sensor W1 has a certified open field tolerance of more than 30 meters.
Field tests demonstrated that the sensor attached to the window can communicate with the switch fitted to the air conditioner without any problems or any latency, even passing through 2 stone walls of 60 cm thickness apiece.

#04 – Is installation simple?
Absolutely! Window Sensor W1 comes with a small radio receiver that is installed on the air conditioner with an intervention on the power supply. The operation is really very simple, and a good electrician can do the job in less than 5 minutes. The receiver must be paired with the sensor (follow the instructions provided with the product) and then mounted on the window, thanks to the handy double-sided tape provided. Having done this simple operation, Window Sensor W1 is ready to control the shutdown of your air conditioner as soon as it detects the window or patio door open.

#05 – Does the component that’s installed on the air conditioner have to remain visible because of the antenna?
No. In fact, the receiver is so small that we recommend installing it inside the split, so that nothing can be seen at all.

#06 – Could multiple Window Sensor W1 sensors interfere with each other?
Absolutely not. During the installation phase (less than 5 minutes in total) the sensor is paired with the receiver via a “unique digital signature.” This makes it impossible for 2 Window Sensor W1 to have the same signature and create interference between them.

#07 – I have a Wi-Fi router in the room. Can Window Sensor W1 affect or be affected by its presence?
Absolutely not.

#08 – Does it also work with fan coils?
Certainly. Installation of the radio receiver requires a minor intervention on the power supply, as mentioned above. This can be done indiscriminately for both regular split air conditioners and fan coils.
Thanks to Window Sensor W1, fan coils will turn off when your guests open the window.

#09 – Is Window Sensor W1 also compatible with all dual and multi split systems?
Generally, yes. In very rare cases, however, and exclusively on dual or multi split systems, the outdoor motor interprets the “absence” of the indoor unit (to which power has been cut off) as an error and goes into lockout. Before purchasing Window Sensor W1 for dual or multi-split systems, we recommend verifying full compatibility by physically disconnecting power to one of the indoor units and verifying that the rest of the system continues to function properly.

#10 – Can I use Window Sensor W1 together with your remote controls?
Absolutely! By doing so you will save even more energy and maximize the benefits.

#11 – Do you need power transformers?
Absolutely not! The Window Sensor W1 receiver runs on a normal 220 volt power supply, while the magnetic sensor takes a normal AAA battery. The product is then ready to be installed with no additional equipment needed.

#12 – Is it safe for my A/C compressor cutting off the power supply to my split air conditioner while it is running?
Absolutely. First, consider that modern HVAC systems are equipped with built-in delay mechanisms to ensure that refrigerant pressures have equalized before allowing the compressor to start.
Second, remember that the practice of interrupting the power supply to air conditioners has been commonplace in hotels for years; the Window Sensor W1 system is a game changer because it does the same thing without the window sensor having to be wired to the receiver installed in the air conditioner.
Even if this first consideration should be enough to reassure you about the use of the system, we can add that throughout the Window Sensor W1 design phase we were advised by the most experienced technicians in the field, who confirmed that due to the way “split type” air conditioning systems work, there is no criticality to interrupting the power supply to either the outdoor or indoor unit.

At SaveOnAirCo we suggest cutting off power to the indoor unit only, firstly because the very limited current draw doesn’t overload contactor inside our receiver, and secondly because, installed in this way, when the power to the indoor unit fan is cut off, the outdoor unit compressor continues to run for a while and then shuts down naturally, controlled by its own circuitry.

However, because we don’t install our own devices, SaveOnAirCo cannot be held responsible for any damage to an air conditioning system, so if you have any doubts, we recommend that you consult your own trusted installer before purchasing our systems.

#13 – Can Window Sensor W1 be installed to monitor 2 or more windows from a single air conditioner?
The Window Sensor W1 system is designed to monitor 1 window per air conditioner. However, you can easily overcome this technical limitation with some additional components – namely a simple and inexpensive monostable relay ( see picture ).

To help you fully understand the usage options, we need to explain in detail how the Window Sensor W1 works: the window/door sensor sends an encoded digital radio signal every time the two parts of the sensor are moved farther apart or closer together. The signal is read by the Window Sensor W1 receiver and when the parts move away from each other (i.e., when the window/door is opened) it is interpreted as “opening the circuit” (type A signal), and power is cut off to the device connected to the Window Sensor W1 receiver. When the parts move closer to each other (window/door is closed), it is interpreted as “closing the circuit” (type B signal) and power is restored to the device connected to the Window Sensor W1 receiver.
Although multiple window/door sensors can theoretically be connected to the Window Sensor W1 receiver, its technology can’t manage multiple devices properly, so the system needs to be equipped with a monostable relay for each Window Sensor W1.

To explain further, let’s assume we have a system with one Window Sensor W1 receiver and two sensors mounted on two windows, which we will call “window 1” and “window 2.”
If we open and then close window 1, the Window Sensor W1 receiver first receives the type A signal, which is the trigger to interrupt the power supply, and then the type B signal, which is the trigger to restore the power supply; the same happens if we open and close window 2.
The problem arises if we first open window 1 and then window 2, and later close only window 1, leaving window 2 open; in this scenario the Window Sensor W1 receiver would receive the signals in this order: A, A, B. When it receives the first type B signal, it would restore power to the device connected to it, even though window 2 is still open.

To permanently fix this issue, you need to install an Window Sensor W1 for each window/door that you want to monitor, and then connect a monostable relay to each Window Sensor W1 (see diagram below), like this FINDER 46.61.8.230.0040 relay.

Once a relay is connected to each Window Sensor W1, the problem will be permanently solved. Until all windows are closed, power to the system will be cut off, regardless of the order in which the windows are opened or closed.