Archive for November, 2009

A zoning system is meant to improve many of the comfort issues you experience while also improving energy efficiency.  The design of some homes may cause challenges with comfortably heating/cooling certain rooms or even entire floors.  Examples may be rooms above garages, areas on concrete slabs or above crawl spaces, rooms with vaulted ceilings, sunrooms, etc.  These scenarios inherently create unique challenges in maintaining even, comfortable temperatures throughout your home.

A basic comfort system will overcompensate for temperature variances in your home by pushing conditioned air throughout your entire home, even those areas that don’t need it.  The result – uneven temperatures and increased energy bills. That’s where the zoning system comes in.

A zoning system consists of a control, automatic motorized dampers and temperature sensors working in conjunction with your comfort system.  The dampers are placed inside the supply ducts to control the airflow to specific areas of your home.  The temperature sensors are located in the separate zones of your home.  It’s similar to having a separate thermostat in each area communicating with your comfort system allowing each zone to be heated and cooled independently.

When any of the zones are calling for heat/cooling (based on your desired set point at your thermostat), the thermostat brings on your comfort system.  The zone control determines which zones are in need of conditioning based on the temperature sensors in each zone.  The dampers are automatically closed in the supply lines to those zones which do not need conditioning and opened in those that do need heating/cooling.

The zoning system allows for you to only heat/cool those areas which need it! This allows you to enjoy more comfortable, even temperatures throughout your home.  Because your system is only delivering conditioned air to the necessary areas, energy consumption is decreased.  Your system operates much more efficiently saving you money on your energy bills.

Unfortunately, zoning systems can’t be installed in every home.  The duct design in your home must be fabricated in a manner which allows for the appropriate zones.  The supply lines must be accessible in order to install the zone dampers, as well. A Comfort Consultant can easily inspect your system to determine whether the zoning system would be right for your home.

In our quest for furthering our expertise of whole house comfort systems, we have gained insight on the effectiveness of humidifiers. First, let me summarize why you might need a humidifier and how they improve your comfort. You may experience static shock in your home, wake up in the morning feeling dry, or have cracking on wood furniture, drywall, etc. These are all signs that there is a lack of moisture in a home. Some homes are dryer than others – The optimal humidity level in a home is approximately 35%, some homes have been measured below 15%!

Your heating system will actually add to these problems because the process of heating the air removes moisture. A whole house humidifier can be installed on your heating system to add moisture to the conditioned air and deliver it through the duct system to your entire home helping to resolve these issues. A home with a higher level of humidity will actually feel warmer allowing you to be more comfortable at lower temperatures. I’m sure you’re familiar with this concept from the weather we experience in Maryland in the summer – It always feels much hotter than it actually is when humidity levels are higher.

Over the years, we have been to many homes in Rockville, Germantown, Gaithersburg and other Montgomery County cities where our customers have humidifiers but they feel as though their home’s air is still too dry. We have found that there are two major opponents diminishing the effectiveness of humidifiers – The first being your own heating system. In order to increase the comfort level in your home, we need to increase the percentage of moisture in the air. However, humidifiers only work when your heating system is actually running so you’re only adding moisture to your home’s air when the furnace or heat pump is on. Most systems only run a fraction of the time and even less if they’re oversized – which many older units are.

The other obstacle is air infiltration. Your home needs to exchange fresh, outside air constantly to be healthy. However, we have found that most homes allow far too much air into the home. An average healthy home would require about 5-7 complete air exchanges each day. We have measured homes with more than twice that amount! This means that the air inside your home is being humidified (not to mention conditioned) and then escaping to the outside. The humidity that you have added is being lost to the outside and you’re humidifier is unable to keep up with the drier outside air that is replacing the air being lost to the outside.

The result: The air in your home struggles to reach the comfortable target humidity levels that you want.

Solutions: We now require an infiltrometer test be performed on any home before installing a humidifier. This allows us to determine the home’s infiltration rate and the amount of moisture needed to reach comfortable humidity levels. With this information, we can determine whether the humidifier will perform as it should. We can also point out areas where simple improvements can be made to decrease the amount of infiltration to the home.

We have also found that certain equipment can help to improve a humidifier’s performance such as variable speed furnaces/heat pumps. These units operate on lower settings the majority of the time resulting in longer run cycles. This allows more time for your system to add humidity to the conditioned air. These systems also allow you to run the fan on lower speeds. The lower speed would allow you to run your fan continuously with the humidifier – providing additional humidification without requiring the system to operate in heating mode.