Do hotel thermostats with motion sensors have you waking up in a sweat?

Question: In the last few years, my husband and I have become frustrated with hotel thermostats. It seems that in an effort to “go green,” some hotels have installed motion-sensor thermostats. This makes sense during the day when we are out, but it poses a problem at night. In the warmer months, we often wake up in a sweat and notice that the thermostat reads several degrees above the set temperature. What is going on? Is there anything that can be done?

Tara Silva

Calabasas

Answer: It is not often, in searching for answers, that one can use the words “Mylar balloon” and “complain” as possible solutions. We’ll get to that shortly.

Meanwhile, Silva is right about this motion-senor business — at least, for one kind of motion sensor.

Frederick Becker, associate professor of hospitality management at York College of Pennsylvania, explains the why behind the technology. “The cost of energy, electricity in particular, is one of the most significant expenses hotels have to deal with,” he said in an email. “No hotel runs at 100% occupancy 100% of the time. When rooms are vacant, there is no need to maintain room temperatures at accepted guest comfort levels. Even when rooms are ‘occupied,’ guests are not in the room 24 hours per day.”

Enter occupancy control systems. “Hotels can both save money on energy costs and be energy-efficient / environmentally friendly,” Becker said.

Alas, those systems that rely only on motion sensors are not always guest-friendly. Unless they’re sleepwalking, guests who are abed aren’t moving in a way that a motion sensor can detect.

The solution for immediate relief is to buy a Mylar balloon (sturdier than a regular balloon) that trails strings or ribbons and let it move around your room, triggering the motion sensor.

If you Google “motion sensors,” “hotels” and “heating and cooling,” you’ll find instructions on how to disable these thermostats. I have no independent knowledge of whether this works, and even if it does, it doesn’t exactly make you an environmental hero.

The longer-term strategy is to complain to the hotel, said Jeff Raber, director of retail and hotels for Schneider Electric, an energy management company and equipment supplier.

A hotelier’s “No. 1 mission is to keep their guests comfortable,” he said. “Guest delight is their No. 1 priority; everything else falls beneath that.”

Although motion sensors are a good idea, they’re not quite a complete idea given that people would rather not spend a night leaping in and out of bed to jog the heating or cooling.

Raber notes that some systems now come with door contacts that can be part of a networked property management system. When you enter the room, the thermostat understands, thanks to a door contact and an occupancy sensor, that people have come into the room and that the system should not fiddle with the temperature, even if the occupants go to bed. When they open the door and leave the next day, the system checks again for motion, then waits 10 to 15 minutes before adjusting the temperature.

Hyatt at Olive 8, an LEED-certified hotel in Seattle, has a system that uses motion and audio detection, along with a key-card system. Many people are familiar with the key-card systems, which are often used in Europe and in Asia. Immediately after you enter the room, you put that key card in the slot and the lights, TV and more are activated. When you leave for the day, you take out the card, meaning you can’t leave on the lights or TV when you’re gone.

With this triple system, motion and audio sensors feel and hear when people are in the room and keep the cooling and heating where a guest wants it. In theory, if you remove the key card, you can’t leave on the TV to trick the system into keeping the temperature where you want it. I say “in theory” because, of course, there are ways to defeat the key-card system, but again, that may put you into the environmental bad-guy category.

The logical question is how will you know what system your hotel has so you don’t show up with a Mylar balloon for no reason. The answer is that you don’t unless you quiz the hotel well before you check in.

Accommodations haven’t done a great job of cluing us in on their systems. But taking a tip from the success many hotels have had in asking us to reuse our towels, perhaps more can be transparent about how their systems work, the consequences of tinkering with them and what the hotel is doing to keep guests comfortable while saving Mother Earth. After all, hotels want guests to have warm memories — just not the kind that involve middle-of-the-night pools of sweat.

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