- Residential Market
- Light Commercial Market
- Commercial Market
- Indoor Air Quality
- Components & Accessories
- Residential Controls
- Commercial Controls
- Testing, Monitoring, Tools
- Services, Apps & Software
- Standards & Legislation
- EXTRA EDITION
“Looking for an office thermostat that actually works? Good luck and Godspeed,” wrote Jared Sandberg of The Wall Street Journal.
“You may never find it. … If you do spy a thermostat, it’s probably locked, or encased behind shatterproof glass.
“Even worse, HVAC experts acknowledge what millions of office workers have suspected all along: A lot of office thermostats are completely fake — meant to dupe you into thinking you’ve altered the office weather conditions.”
Thus it was, on Jan. 15, that the consumer media blurted out a practice sometimes applied in the HVAC industry — some thermostats aren’t installed to interact with the HVAC system.
The jury is still out on whether or not they work.
Happy StatsThe manufacturers contacted for this article expressed either general or specific disapproval of the intentional use of nonfunctional thermostats. Many engineers, contractors, and wholesalers in the HVACR industry agree that the intent of installing nonfunctional thermostats is to satisfy the comfort needs of building occupants without giving them a direct interface to the mechanical system.
In many cases, the placebo effect of the nonfunctional thermostat seems to be successful.
“I worked at the [retailer] at [a shopping mall] and we had an employee that always complained of being hot,” recounted Greg Perakes, an HVACR instructor in Murfreesboro, Tenn. “Our solution was to install a pneumatic thermostat. We ran the main air line to it inside of an enclosed I-beam. Then we just attached a short piece of tubing to the branch outlet (terminating inside the I-beam without being attached to any valves, etc.).”
The employee “could adjust her own temperature whenever she felt the need,” Perakes said, “thus enabling her to work more and complain less (as could we). When she heard the hissing air coming from inside the I-beam, she felt in control. We never heard another word about the situation from her again. Case solved.”
Perakes’ reply was similar to many The News received from an informal survey, “Have you installed ‘dummy’ thermostats?” on our Web site. A total of 70 responses were received; 51 replied that yes, they had installed dummy stats; 19 replied no, they had not.
Former News Editor Tom Mahoney, of Bloomfield Hills, Mich., recalled that respected HVACR engineer Joe Olivieri (also a contributing editor to The News) “always said that ‘thermal comfort is 90 percent mental and 10 percent physical.’
“He also said something I found very interesting,” remarked Mahoney. “He compared the fake thermostat to a placebo, a fake pill given by doctors to patients who have imaginary aches and pains. Today, placebos are even given in controlled experiments to substitute for some types of surgery. Your leg aches, the doc opens up your thigh, then closes it right up. You feel better right away.”
In the case of nonfunctional thermostats, part of this placebo effect could be due to homeostasis, defined by Webster’s New World College Dictionary as “the tendency to maintain, or the maintenance of, normal, internal stability in an organism by coordinated responses of the organ systems that automatically compensate for environmental changes.” In short, it is the physical ability to adapt to environmental surroundings.
I Think, Therefore I Am (Hot)Mary-Louise Kean, a professor of cognitive sciences with the University of California-Levine School of Social Sciences, specializes in “cognitive neuropsychology and the biological foundation of higher mental processes.” In a 1995 paper, she pointed out, “Homeostasis involves the balancing of activities between the parasympathetic and the sympathetic nervous systems.” Here is Kean’s description of how it works — as a control system. (It is remarkably similar to thermostatic and BAS controls.)
“Normal human body temperature fluctuates around the value of 98.6 degrees F. … As long as the internal body temperature is within the biologically defined optimal range, there are no problems associated with temperature. If the external environment gets very hot, unless some mechanism counteracts this heat, the internal temperature will rise above a healthy level. In the human body, the parasympathetic system is aroused when an upper temperature level is reached.
“When the parasympathetic system is aroused in this way, several changes take place in the body. First is vasodilation: The blood vessels widen so that more heat can radiate away from the body. Secondly, sweat is produced, and this sweat, when it evaporates, serves to cool the body. Through these and various other mechanisms, the body reacts to externally induced elevation of internal temperatures and manages to maintain an appropriate and relatively consistent internal temperature.
“At the other extreme, when the external temperature is very low and threatens to drop below a healthy range, the sympathetic system is aroused. Several events take place as this happens. One is vasoconstriction: the blood vessels constrict inside. When the blood vessels have decreased in size, they radiate less heat than before; thus the body loses less heat. Another important reaction is shivering. Shivering helps generate warmth because of the sheer muscular activity it produces.
“On the other hand, there are other options available which add a layer of complexity to the story of temperature control. If a person is cold, he or she has the option of putting on a sweater, seeking shelter, or increasing indoor temperature of his or her home. ... Thus, not only does the biological system contribute to a relatively constant internal temperature, but humans (and some other animals) can make use of their cognitive abilities to contribute to keeping the homeostatic balance.”
So, say that an office worker feels too hot. The individual begins to perspire, makes an adjustment to the nonfunctional thermostat, gets a cold beverage, and closes nearby curtains. That person could certainly believe that adjusting the nonfunctional thermostat controlled the situation, although the real mechanism was homeostasis.
Dan Int-Hout is chief engineer for Krueger, a manufacturer of grilles, registers, terminals, and diffusers, headquartered in Dallas; former chair of the ASHRAE Standard 55 (Thermal Environmental Conditions for Human Occupancy) committee; consultant to 62.1, the Commercial Indoor Air Quality committee; and a member of the technical committee on physiology and the human environment.
“Your metabolic rate will come into balance with your environment,” he stated. “Your body does something — goosebumps, sweating, or chills if you are too cold — that brings your body temperature into balance with your environment.”
He also believes that in some cases, nonfunctional thermostats are the solution for building occupants who may not feel thermal discomfort, “but who want to have a degree of control.”
According to many respondents to The News’ survey, this constitutes a large portion of the occupants for whom nonfunctional thermostats are installed. For instance:
“The space renovations included the installation of two new rooftop air-handling units (AHUs) with DX [direct exchange] A/C and natural gas heat exchangers. That first season change from summer to fall, our staff was overwhelmed with requests to adjust the space temperatures. In the morning when it was cool outdoors, we would receive calls to raise the temp and then in the afternoon when the outdoor temp would rise, we would receive calls to lower the space temp.
“We had checked the operation of the control system and found everything to be in working condition,” Langless wrote, “and had made program changes to alleviate the problems. Even though we were sure our system was working as it should and maintaining space temps to within 1 degree to 2 degrees, we could never completely satisfy the occupants of the space. We mounted a ‘dummy stat’ adjacent to the ‘controlling stat’ and gave the floor manager the key to the stat — now the occupants could ‘control’ their space as they desired with the permission of their manager.
“The dummy stat did nothing except to give the occupants the impression that they had control of the HVAC system,” Langless wrote, “and the psychological effect of having control of their work environment. Our service calls disappeared, and to my knowledge, that system is still set up and working as it has since 1987.”
Tell The DecisionmakerIt is critical that if a contractor decides that use of a nonfunctional thermostat is justifiable, that he tells a decisionmaker that such a thermostat is part of the plan. Steve Carey, director of Aftermarket Marketing for White-Rodgers, part of Emerson Climate Technologies, pointed out that happy stats “are not used to trick the decisionmaker. It’s obviously done for a legitimate reason — not to negatively impact comfort.”
“The owner of the building needs to be made aware of it,” agreed John Sartain, White Rodgers’ Market Manager — Thermostats.
Sartain said that he knew of cases where nonfunctional thermostats were installed to protect the equipment, and the temperature was “repeatedly being adjusted up and/or down” by building occupants having “thermostat wars” (cases where one occupant is too hot, then the other is too cold, and thermostats are raised and lowered all day). “You can end up damaging the equipment due to short starts” and related problems, he said.
In other cases, thermostats installed in high-traffic areas were subjected to some pretty appalling abuse, including burning with cigarette lighters. “We serviced a lot of canteens,” Sartain said. “In some of those applications, thermostats were brutalized.”
When a nonfunctional thermostat was installed, “The manager of the canteen knew where and how to control a functioning thermostat,” Sartain said. Newer products with remote sensors allow control of the dining room from a remote location, he added.
“In a canteen or restaurant application, the goal is providing customer comfort via controlling temperature in the public area,” Sartain explained. In these public areas, a thermostat guard “by its very presence makes thermostats vulnerable to tampering. Most people can identify a thermostat or a thermostat enclosed in an opaque or metal guard. So a secondary goal in some applications is to keep the public and others from ‘playing’ with the setting and possibly causing discomfort or equipment damage.”
By using a remote sensor, “the thermostat itself can be positioned in a more secure location, like the manager’s office. Our Comfort-Set 90 Series products offer remote sensor capability. The single-stage models can use one remote sensor, and the multistage models can use up to three remote sensors, plus the local sensor within the thermostat. A weighted average allows the contractor to give more priority to different sensors throughout the day.”
Other thermostat manufacturers, such as Honeywell, also offer sensor-based systems with a variety of interfaces. For example, in commercial buildings over 50,000 square feet, “Various parts of a building would have a sensor on the wall wired into the central controller. These … sensors are usually the shape of a large matchbox with a stainless steel or white plastic cover.
“In some cases,” the company explains, “the temperature can be adjusted locally; however, it depends on how the system is configured. … Typically in situations where temperature control is ‘distributed’ and not local, an occupant would call the building manager to have the temperature adjusted.”
Mechanical system protection is a big reason for the installation of nonfunctional thermostats. “As a service tech years ago, I have used them in a visiting room,” said Ted Klosterman of Bellevue, Ky. “We had a big problem with persons wanting to play with the stat lock boxes — I made a duct stat out of two temp controls and when I was done, all the room stat did was tell you the temp in the room.
“This was more for the good of the unit than anything. We always had to clear the coil of ice when someone would turn the stat to 50 degrees; it also saved on compressor replacement. Before I did this, we lost two compressors; no compressors were lost that summer due to too many hands on the stat.
“The funny thing was, they would mess with the stat and think it was doing something; as long as they could play, they were happy,” wrote Klosterman. “Funny how things work.”
According to research from Johnson Controls, “Numerous studies show that investing in the indoor environment can be justified on the basis of productivity improvements alone.” The company’s solution is its Personal Environments® workstations, at which a desktop control unit gives the desk occupant the ability to adjust temperature, lighting, airflow, and acoustics.
“Improvement to the workplace environment is a highly cost-effective way of enhancing employee satisfaction, productivity, and the company bottom line. According to two researchers, the ratio of building operation costs to average salary costs is 1:13. A company would have to eliminate more than a month’s worth of building operating costs to pay for just two days of lost worker productivity.”
Check The Equipment“If you have the opportunity to give the public control over their environment, you should,” said Dan Int-Hout. “Locked thermostats in a nonpublic building are demoralizing” — it sends the message that management doesn’t trust the employees.
Int-Hout said that at one jobsite, he removed the locked covers, then held a thermostat class for building occupants. It included information on “Here’s the guy to call” with comfort complaints.
Also, in cases where it seems that all females are complaining, perhaps service contractors should look for signs of air stratification. If air diffusers are not selected, installed, or maintained properly, it could result in colder air at the foot/ankle level than at the neck level: vertical temperature stratification. In these cases, women complain, men don’t. This happens because women are more likely to wear nylons than heavier socks, Int-Hout pointed out.
According to Int-Hout, placebo stats can indicate a system problem. “If it’s cold at the floor level, take an $18 Radio Shack indoor-outdoor thermometer; set it on a desk, and dangle the bulb to the floor level.” If the measurements detect stratification, repairs probably would involve rebalancing the system, Int-Hout said.
Placebo thermostats can sometimes solve chronic complainers, he said. However, “Sooner or later they figure it out. We need to make sure equipment is working properly.”
Doug Huberty in St. Paul said it nicely: “If you fix the problems causing the too-hot, too-cold complaints, the staff forgets there is a thermostat on the wall.”
Publication date: 03/31/2003