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Al’s Plumbing, Heating & A/C, in Plano, Texas provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s Plumbing, Heating & A/C is near your home in Plano, Allen, and Frisco.  We service all homes in southern Collin and Denton Counties with no additional travel charge.

Al’s also provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally, we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.

photo of a new home

Image Source: Pixabay.com

Two Story Homes Are Always Warmer Upstairs Than On The Ground Level

This article is about Zoned HVAC Cooling & Heating.  Zoning allows different areas of the home to be different temperatures. It allows areas that are seldom used to have little or no cooling / heating, while other areas are cooled / heated more of the time.

Zoned HVAC also allows different areas in the home to be different temperatures at different times of the day.  Often during summer, bedrooms are allowed to be warmer during the day, and Daytime Living Spaces to be warmer overnight.

  • With Zoned HVAC Typically There Are 2 Or More Separate HVAC Systems. 
  • In DFW, homes up to 2,000 square feet need only 1 HVAC System. 
  • This Article Is About Using ZONE DAMPERS to get the Comfort Benefits & Energy Savings Of Zoned HVAC — With 1 HVAC System.

Image Source: DreamsTime

Click Here To See Two-Zone HVAC Using Two Separate HVAC Systems: Two-Zone HVAC With Two HVAC Systems

Click Here To See Two-Zone HVAC Using One HVAC System: Two-Zones With One HVAC System

Click Below For A Video Explaining How Zoned HVAC Dampers Work:

Zoned Damper HVAC System Video

In a one HVAC System home, Zoning is accomplished with Electrically Operated Dampers.  Each damper(s) has its own thermostat that operates only those damper(s).   This can provide as much flexibility as the home owner would like when controlling the temperature in different zones of the house.  For example, during summer, the bedrooms can be allowed to be warmer during the day, and daytime living space is cooler.  At night, the bedrooms become cooler while the daytime living space is warmer.

Zone Dampers Are Particularly Valuable In 2-Story Homes. The upper story will always be warmer than the first floor because heat rises.  Additionally, in summer, the sun is shining on the roof and the attic get very hot (attic temps can reach 160+ degrees during DFW summer).  Some of the heat in the attic forces itself into the rooms, making them much warmer than the first floor rooms (that have air conditioned rooms above them).

Click Here To See A Thermal-Image Photo Showing Attic Temperature: Thermal Image Photo Shows Attic At 170 Degrees!

Zoned HVAC allows the homeowner to have as much as individual room temperature control.  This offers tremendous comfort advantages.  During DFW summer, west facing rooms will be notably warmer than east facing.  During winter, north facing rooms will be notably cooler than south facing rooms during the day.  Zoned HVAC allows more cooling or heating to be supplied to the rooms that are becoming warmer due to the sun.

With comfort being a major factor in the decision to install Zone HVAC, the dampers will also pay for themselves over time.  Zone dampers reduce how much the HVAC System must run, lower cooling & heating bills and extending the lifespan of the HVAC System..

Shown: Electrically Operated Zone-Damper

Click On Image To: View Product, See Details, or Purchase From Amazon.com

Zone Dampers are installed in the ductwork (typically in the attic of a DFW home).  They are installed at the same time a the HVAC System is installed.  If the existing system is a Variable Speed HVAC System, zone dampers can be added to the existing system.

Click Here To See An Example Of A Retrofit Zoned Damper System Installed In An Existing Home: Zoned Dampers Added To Existing Home

 

Single-Speed HVAC Systems Are Not Designed For Zone Dampers

electric furnace

Image Source: CanStockPhoto

Single-Speed / Single-Stage HVAC Systems Run Only At 100% Capacity.  They Cannot Run Faster Or Slower. 

The majority of HVAC Systems are Single-Speed.  All brands of HVAC also offer Variable-Speed Systems. Variable-Speed Systems are more expensive to buy, but less expensive to operate because they operate only at the speed needed for the current cooling / heating demand at any given time.  If it’s 80 degrees outdoors, the System will operate more slowly (and uses less electricity) than when its 105 degrees.  Like a car, Variable-Speed HVAC uses less electricity when running a less than full speed.

Installing dampers inside existing ductwork is the most common way to add zones to an existing system.  However, with a Single-Stage / Speed  blower (& outdoor A/C unit) it can only operate at 100% capacity.   For Example:  You have a two story home and want to cool only the upstairs at night.  The Zone Damper(s) turn off airflow to the first floor. This causes pressure to build up inside the ductwork.  This causes the HVAC System to operate much differently than it was designed & installed to.

 

Click Below To Read An Article About Problems With Single Speed HVAC Systems & Zone Dampers: 

Zone Dampers & Single Speed HVAC Systems

 

Adding a By-Pass Damper allows excess air flow (due to some duct(s) being closed) back into the Return-Air ductwork.  This eliminates the pressure build up inside the ductwork, but causes additional problems.

Problems Caused By A By-Pass Damper:

  • During Cooling Season, the By-Pass Damper adds recently cooled air back into the return air ductwork.  This causes the A/C Cooling-Coil (inside the furnace or ductwork & can’t be seen) to become too cold.  The colder the Cooling-Coil becomes, the less efficiently the A/C operates.  Plus, over time, the Cooling-Coil can freeze.  This coil is what removes humidity from the air.  So, if the coil becomes too cold, the humidity freezes within the coil instead of draining away.
  • Another problem will be too much humidity inside the home during summer.  Because the air is passing through the Cooling-Coil too fast (due to dampers being closed) — the Cooling-Coil does not have adequate time to remove the humidity.  The HVAC System & Cooling-Coil were designed & installed to have all air vents open and supplying air to all rooms all the time.

Click Here To See A Frozen Cooling-Coil Inside A Furnace: Frozen A/C Coil inside furnace

If the System is allowed to run with a frozen indoor Cooling-Coil for a prolonged period of time, it will damage the outdoor unit.  This situation can cause the outdoor unit to freeze too.

frozen outside air conditioner unit

Image Source: ShutterStock

SHOWN: Frozen Central A/C Outside Unit

  • During Heating Season, a by-pass damper causes the furnace to run too hot.  The burners are making enough heat to warm the entire house, but only portions of the house are receiving heat.  Air being is being returned to the furnace (through the by-pass damper) at a much warmer temperature than the furnace was designed to receive.
  • To accommodate air that’s too cool or too hot, the HVAC System “short cycles”.  This means it runs for shorter periods of time.  Short cycling starts & stops the HVAC System much more frequently than it was designed for.  This results in shortened HVAC System life, and makes for an uncomfortable home because the air coming from the ducts is too hot or cold to feel comfortable.

Imagine while driving your car if you stopped at every intersection.  Your car’s brakes would wear out much faster than if you drove the car the way it was designed to be driven.  This is what short-cycling does to an HVAC System.

Zone-Dampers Are To Be Installed With Variable-Speed HVAC Systems

central air conditioner outside unit

Image Source: DreamsTime

Variable-Speed HVAC Systems Run Slower Or Faster Based On Cooling or Heating Demand

Zone Dampers are to be installed with a Variable-Speed HVAC System.  This means both the furnace blower and the outside unit can slow down / speed up based on current cooling / heating demand.

When operating with Zone Dampers closed, the system will slow the airflow + the amount of cooling the outside A/C is supplying.  When zone(s) are closed.  A Variable Speed HVAC System will deliver only the amount of airflow required to cool / heat the spaces the Zone Dampers are sending air into.  This reduces the amount of electricity the air conditioner uses.

Click Below To See American Standard’s (same company as Trane) HVAC Systems Product Line: 

American Standard HVAC Systems — (Then Click On Air Conditioners)

The first systems you see are Variable Speed Systems (Accurate Comfort Platinum 18 or 20 SEER A/C Units).  After that the single speed systems are shown.   A matching Furnace is required.  This allows the blower fan motor to speed up / slow down depending on the volume of airflow required at any given time.

Zone Damper(s) each have their own thermostat.  This thermostat operates only the zone damper(s) it’s connected to.  Multiple Zone Damper(s) can be installed on one HVAC System, each with their own dedicated thermostat.  When the thermostat calls for cooling / heating — the damper opens.  Once the temperature reaches the thermostat’s setting, the Zone Damper closes again.  This allows the owner to keep each zone at exactly the temperature they want 24 hours a day.

All this can be automated with a Smart Thermostat or Automatic SetBack Thermostat.  Once programmed, each zone is cooled / heated based on the thermostat’s programmed setting.

nest thermostat in heating mode

The Nest Thermostat Is One Of The Most Popular Smart Thermostats

Click Here To Learn More About The Nest Thermostat: AlsPlumbing.com Benefits Of The Nest Thermostat

 

Click Below To See Different Cooling / Heating Zones In 1 Home With 1 Variable-Speed HVAC System & Dampers:

Home With Multiple Cooling / Heating Zones

 

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Al’s Plumbing, Heating & A/C, in Plano, Texas provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home. Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s Plumbing, Heating & A/C is near your home in Wylie, Murphy, and Rowlette, TX.  We service all homes in southern Collin and Denton Counties with no additional travel charge.

Al’s also provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally, we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.