One comfort issue that can be a daunting task for a property manager is the difference in perception of comfort levels from one occupied area to another. This problem is often exacerbated by individual temperature preferences.
Several factors can contribute to temperature irregularities, including: different temperature parameters, uneven loading, different designs, different activity levels, different uses in space, incorrect air flow, incorrect zoning, systems with the wrong size, location of air distribution devices, faulty cooling or heating equipment or human factors.
Understanding how different solutions may be related to another problem can help you gather the information your construction engineer or mechanical contractor needs to help you solve the problem. In many cases, there may be more than one factor that actually leads to a tenant's complaint. It is important that the main factor (s) is clearly understood before an attempt is made to solve the problem.
Let me turn to a few of the most common things that often lead to complaints of comfort.
When the air conditioning system is designed by a mechanical engineer, calculations are performed to determine exactly how much air flow is required to ensure sufficient cooling or heating in the zone. Then individual areas are grouped into large spaces that have similar cooling and heating requirements. These spaces are called zones.
The number of tenant complaints we receive are the result of changes in usage that cause improper zoning or improper airflow. This is especially true if the tenant improvement contractor does not include a mechanical engineer for redesigning the air conditioning system for new use of the tenant space. The following scenario is an extreme example of what could be the result of such a course of action.
Imagine that the original design in an existing open office space is designed for a single AC unit. The new tenant has the requirement to build a server room in the center of the area. The tenant decides to use the existing air conditioning system to cool both the office space and the new server room. The server requirement is a temperature of 72 degrees inside the room around the clock. The desired temperature of office space in the tenant's room is 76 degrees for 8-10 hours a day.
The first thing we notice is that now the requirements of time and temperature for these two areas are not at all similar. Where do we place a thermostat or a zone sensor so that everyone is happy? If we put a thermostat or zone sensor in the server room, there will always be demand for cooling. How will this affect the office space? The office area will become too cold. If we place a thermostat or zone sensor in the office area, how will this affect the temperature in the server room? The office will be comfortable, but the server room may become too hot. How to solve this problem? The ideal solution would be to install a dedicated AC unit for the server room.
Although this is an extreme example, we are constantly faced with similar zoning problems in the real world. Perhaps this is not a server room and an office that is involved, but when the heating and cooling requirements for each area are significantly different, there will be complaints about comfort.
Another factor that can cause complaints about comfort is an improperly balanced flow of air. Over time, the dampers in the duct system can be adjusted by contractors who have the sense to try to solve the problem of localized comfort in the zone. When people move to other areas in the zone where the air flow is adjusted to meet the previous comfort problem, the shock absorbers can be adjusted again. Each time the air flow changes in one part of the zone, opening or closing the damper, the air flow will be changed through other areas in the zone. Soon the airflow of the entire air distribution system becomes unbalanced. In extreme situations, we saw pieces of cardboard pasted on the face of the recorders to completely block the flow of air.
As for each space that requires a certain predetermined amount of air flow to maintain a given temperature, with insufficient or excessive air flow, tenants will not be satisfied. Professional balancing the entire air distribution system in a problem area can be time consuming and costly, but sometimes this is the only way to restore satisfactory performance.
Another common source of comfort is complaints from different departments serving the same territory. You can imagine what can happen when one system calls for cooling and the other for heating. Below is one possible scenario illustrating how this situation can occur.
Mr. Printsilal has a corner office with a view of the south side of the building, in the middle of summer and with the lord. The director is too warm. The contractor, who knows the meaning well, looks at the duct supplying air and concludes that there is not enough air. Considering the problem, he decides that the most economical thing to do is to launch several additional channels to the office of Mr. Principal from the unit serving the internal office area. He proposes this idea, his proposal is accepted, and he makes definitions of air ducts. During the summer, everything works very well, because both zones require cooling.
In winter, everything changes. The office of Mr. Principal, which is an external wall with a large amount of glass, now needs to be heated in the morning, not cooling. The only problem is that the internal office space warms up much faster than the room with the view and begins to cool. Since Mr. Glavny’s office is managed by divisions serving two different zones, they are now fighting each other, and Mr. Principal is unhappy.
One way to determine and resolve such a situation is to force your construction engineer or mechanical contractor to map the problem area zone. Draw in the rooms, and the channel works exactly where they are now, and see where each piece of air duct comes from. It's amazing what you find! If you make a zone map correctly, you will learn what you need to do to solve many of the problems described above.
The following method can be useful for mediating a truce in thermostats and during zones-probes! A thermostat or zone sensor actually controls only the temperature in which it is located. Several separate work areas can be cooled with one air conditioner. See if you can force the tenant to agree that only one person will be responsible for setting the temperature. Help residents mutually agree on a given point, which is reasonable for all parties affected by this unit. This is ideal if you can buy for one cooling temperature and one heating temperature for the entire tenant's premises. Tell the people who are calling (if they are not the responsible party) that you have agreed to accept the calls only from the person responsible for setting the temperature and send them back to the responsible party. This requires the support of the responsible party to ensure compliance with the new target values, but may significantly affect the reduction of the requirements for the complaint to the real estate administrator.
In the case of an occupant with unreasonable expectations or that, in your opinion, complaints about comfort may be exaggerated, it is useful to obtain data on actual temperatures in their area during a certain period of time. There is a reliable, inexpensive device called a data logger that allows you to do just that. After leaving the data logger in space for a reasonable period of time, the data can be downloaded to your computer and then displayed or printed as a graph. Samples of time periods are determined by how you initially set up the data logger.
Most of the time, when we use a data logger to examine a comfort complaint, the air conditioner works correctly, as indicated when the temperature swings from 1 to 2 degrees every other day with rights. In some cases, however, we find that the passenger was justified in complaints of wide fluctuations in temperature. The important point is that we now received accurate information from the data logger, which will help to correctly identify and solve the problem for the tenant.
