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This Article Discusses How A High Efficiency Furnace Can Lower Heating Costs IN DFW.

photo of colorful fall leaves

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Fall Is The Time For A Furnace Tune-Up.

Fall Is Time To Consider If You Need To Replace Your Furnace.

Al’s Plumbing, Heating & A/C in Plano, Texas 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).

Al’s also 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 is near your home in Plano, Allen, and Frisco.  We service all homes in southern Collin and Denton Counties with no additional travel charge.

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.

High Efficiency Furnace —  Is It Worth The Extra $ In DFW?

electric furnace

Image Source: CanStockPhoto

 SHOWN: A High Efficiency Furnace Has Plastic Exhaust-Vent Pipes because the exhaust is much cooler than a Standard Efficiency Furnace.

When Replacing A Gas Furnace, There Are Two Choices:

  • Choice 1: Standard Efficiency:  80% efficient.  20% of the heat generated goes out the flue.
  • Choice 2: High Efficiency Furnace:  92 — 98% efficient.  Only 2-8% of the heat generated goes out the flue.

What Does A High Efficiency Furnace Do Differently?

High-E furnaces remove much of the heat from the exhaust gasses.   That is done by routing the gasses through a 2nd Heat-Exchanger that is for only the exhaust.  It’s called the Secondary, Condensing Heat-Exchanger.  This device allows the furnace to recapture most of the heat that goes up the flue with a Standard Efficiency furnace.   Depending on the Brand, Model & Grade of the furnace, as little as 2% of the heat generated is sent up the flue with a High Efficiency Gas Furnace.

Because the exhaust gasses are so cool, they are vented through plastic pipe.  When 2 plastic pipes are present (which is nearly all High-E furnaces) — that means air for combustion is brought in from outdoors, versus the air being pulled from the furnace’s environment.  With an attic installation, this feature does not add to the overall fuel savings.  If the furnace is located within the heated living space of the home, additional savings are created by using outside air for combustion versus (heated) indoor air.

Click Here To See A Diagram Of  A High Efficiency Gas Furnace: High Efficiency Gas Furnace Diagram

(The Secondary Heat Exchanger Is Identified On The Left Side Of The Image, Near The Center)

How To Decide If A High-E Furnace Is Worth The Cost For Your Home 

close up photo of gas furnace flames

Image Source: ShutterStock

  • Home Advisor states the upgrade from Std. Efficiency (80%) and High Efficiency Furnace (92-98%)  = +$1,000-$2,000 (upgrade price based on furnace size).
  • Ask your contractor the difference in price between 80% and High-E furnace for your home.
  • Total Last Year’s Gas Bills.
  • Note: You don’t need to adjust for gas: cooking, water heating, or clothes dryer.  Those number remain the same regardless of furnace efficiency choice.
  • Reduce The Total $ Spent For Gas Last Year By 12-18% — based on the efficiency rating of the High Efficiency furnace
  • Take the annual saving by 15 — 15 years is the expected lifespan of the furnace.
  • Compare The Upgrade Charge To The 15-Year Expected Savings.
  • Choose What Costs You Less.
  • OR, perhaps a better choice is to spend the furnace upgrade cost on Energy-Saving Upgrades for the house.  We detail the primary upgrades below.

Is The High-E Upgrade Money Better Spent On These

Energy-Saving Upgrades?

1. Adding Insulation

photo of blown insulation in an attic

Image Source: ShutterStock

Texas Homes Insulation Levels That Were Common Or Became Required By Building-Code”

           Attic Insulation                           Wall Insulation

  • 1950’s: none                                     none
  • 1965-1970: R-13 (3.5″ BATT)      Wall Insulation: R-6 (2″ BATT)
  • 1970’s: R-19 (6″ BATT)                  Wall R-6  (2″ BATT)     *3
  • 1980’s: R-30 (9″ Blown)                Wall R-13 (3.5″ BATT) *4
  • 2014:    R-38 (15″ Blown)               Wall R-15                        *5
  • *3 Source: https://snuggpro.com/blog/item/many-homes-built-prior-to-1980-were-built-without-insulation-in-the-walls
  • *4 Source: https://www.jlconline.com/how-to/insulation-code-change_o
  • *5 As required by the 2012 Edition of the International Building Code (IBC)

Does Your Attic Floor Have The Insulation Depth / Thickness Required For At Least R-38?

15″ of Blown Insulation is required for R-38 (less thickness if a BATT of insulation is at the bottom).    If you have less than R-38 insulation, it’s likely more cost-effective to spend the additional money (to upgrade from Standard Efficiency To High Efficiency Furnace) on insulation instead.

The cost to insulate your attic to at least R-38 will likely be similar to the High Efficiency Furnace upgrade charge.  Both a High-Efficienct furnace and attic insulation will lower heating costs.  Attic insulate will also lower cooling costs.

To Learn About Attic Insulation, Click Here: AlsPlumbing.com Lower Heating Costs With Attic Insulation

 

2. Ductwork Sealing

If Your Home is More Than 10 Years Old, Your HVAC Ductwork Is Likely Leaking

Up To 30% Of Heated & Cooled Air Into The Attic

ductwork for hvac system

Image Source: ShutterStock

The U. S. Department of Energy (DOE) estimates typical homes lose up to 30% of the heated & cooled air from ductwork through holes, leaks, and loose connections. 

If you install a new HVAC System, the contractor may want to replace existing ductwork.

  • If the existing ductwork in flexible, it needs to be replaced because it only lasts the lifetime of one furnace.
  • If the ductwork is metal, it may not need to be replaced.  Unless the new HVAC moves about the same amount of air when the blower-fan is running, the existing ductwork will work just fine.  If the new System moves notably more air, the existing ductwork may be too small.  That does not necessarily mean it won’t work.  It may be able to be modified to accommodate the larger airflow.
  • If you don’t replace existing metal ductwork, have it tested for leakage and resealed if necessary (it likely needs resealed).  Your Contractor can do that.

Resealing Existing Ductwork Can 

Lower Heating & Cooling Costs By Up To 1/3!

Ductwork in older homes may not have been sealed when installed.  In other cases, duct tape was used.  Duct tape fails within days.  Today duct work is sealed with non-hardening mastic at the seams and connections.  Mastic can withstand temperatures in DFW attics during summer without failing.

Click Here To See Ductwork Sealed At Seams and Connections With Mastic: Ductwork Sealed With Mastic

Max Sherman & Iain Walker of the DOE’s Lawrence Berkeley National Laboratory performed a” bake-test” in which sample ductwork joints were baked at temperatures of 140 to 187F to test different ductwork sealing products.  They stated “Only one duct-tape product survived 3 months of the aging test.  11 Duct Tape products failed within days.” **

**Source: http://www2.lbl.gov/Science-Articles/Archive/duct-tape-HVAC.html

Contact Al’s Plumbing, Heating & A/C For A Ductwork Leakage Test.  We can measure the amount of air going into the furnace and compare it to how much air is exiting the air vents to determine how much leakage exists.  We Also Provide Ductwork Sealing With Mastic.

Click On The Links Below To See Examples Of What Is Found During Ductwork Inspections:

Leaking Ductwork – 1

Leaking Ductwork – 2

Damaged / Collasped Flexible Ductwork – 3

3. Weatherizing – Sealing Air Leaks

photo of a new home

Image Source: Pixabay

 Today, A New home exchanges about 1/2 their indoor air with outside air (through leaks or ventilation) each hour.

A 1970’s home exchanges indoor air with outside air as many as 17 Times Each Hour (through leaks)

If you live in an older home, you can buy the 80% efficient furnace and spend the upgrade cost (for High Efficiency furnace) on Weatherizing & Insulating your home instead.  We provide details below that demonstrate why you may reduce heating & cooling bills more with Energy-Saving Upgrades to the house than with an upgraded furnace.

  • Air Changes Per Hour (ACH) is a rating system to determine the rate indoor air exchanges with outside air each hour (through air leaks).
  • Today’s Standard is a minimum ACH for a home is .35.  This means at least (just over) 1/3 of indoor air must exchange with outdoor air each hour.
  • If a home does not have at least .35 ACH Indoor Air Quality will be unacceptable.
  • A DFW Energy Star Rated Home can have not more than .5 ACH (half of all indoor air exchanges with outside air each hour).
  • Because new homes are built so airtight, many have mechanical ventilation equipment to ensure at least the minimum .35 ACH per hour.
  • A 1970’s Built Home Has Up To ACH! *

* Source: http://www.greenbuildingadvisor.com/blogs/dept/musings/revisiting-energy-saving-handbook-1979

Where Air Leakage Occurs In Homes

Click Here To See A Pie-Graph Of Air Leakage Locations:  Home Air Leakage Locations

  • 31% Openings in Floors, Walls & Ceilings

You might think “How can a ceiling leak air?”  The leaks are at the openings in the ceiling.   Most older homes have gaps around electrical boxes.  Because these leaks are in the ceiling (heat rises), they present a great opportunity to lower heating costs.

To seal the gaps, use caulk or spray-foam (for gaps too large for caulk).

  • Most DFW homes have HVAC Vents in the ceiling.  Older homes will have gaps around the vents — and not visible due to the vent cover.

Click Here To See Gaps Around Ceiling HVAC Vent: Gaps Around Ceiling Vent

Click Here To See An Example: Gap Around Ceiling Light Box

Click Here To See An Example:  Gap Around Bath Vent In Ceiling

  • This includes air leaking into the home where the walls meet the floors

Click Here To See Air Leakage Where Floor & Walls Meet: Air Leakage At Floor

  • 15% Leaking From Ductwork
  • 14% From Fireplaces with damper left open (when not in use) OR have a damaged / warped damper that cannot close properly.

Click Here To See Damaged Fireplace Damper That Does Not Close: Damaged Fireplace Damper Does Not Close

  • 13% Plumbing Penetrations Through The Walls

Click Here To See A Large Gap Around A Plumbing Penetration: Large Gap Around Plumbing Penetration

  • 11% Exterior Doors

Click Here To See A Gap Under An Exterior Door: Gap Under Exterior Door

  • 10% Windows

The biggest source of air loss through windows occurs when they are left unlocked.  Locking the window pulls the upper & lower window sashes more tightly together.

unlocked window with gap between sashes

Image Source: ShutterStock

Notice The Gap Between Upper & Lower Window Shashes In This Unlocked Window

  • 4% Exhaust Fans & Vents
  • 2% Electrical Outlets & Switches

Click Here To See A Gap Around An Electrical Outlet Box:  Gap Around Electrical Outlet Box

Click Here To See A Thermal-Image Of Cold Air Leaking Into A Home During Winter: Thermal Image Shows Air Leakage

 

Upgrade Old, Vented Recessed Light Fixtures

  • One Of The Worst Offenders On Heating Costs Are Old, Vented Recessed Lights.
  • Older fixtures have vent holes to allow heat from the light bulb to escape.  They create a 24/7 air leak into the attic.
  • Add to that, many have an open gap between them and the opening in the ceiling.

Click Here To See An Older Recessed Can Light With Vent Openings (to the attic): Old Recessed Light With Vent Holes

Click Here To See A Common Installation Of A Can Light: Recessed Can Light With Gap In The Ceiling Around It

  • Most newer recessed lights don’t have vent holes.  You still need to check if there is an unsealed gap between the ceiling and the light fixture.
  • There are Non-Vented, Retrofit, Recessed Light Fixtures that connect by simply screwing their connection into the light bulb socket in the existing fixture.  You don’t have to remove the old fixture!

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

  • These new fixtures come with an LED bulb available in cool or warm white light.  The fixture shown produces 100 watts of light using only 15 watts.
  • LED bulbs produce little heat (that your a/c must remove).
  • Once sealed to the ceiling, these fixtures won’t allow heat to rise into the attic.
  • These Are An Easy DIY Replacement, No Wiring Required.   They are modestly priced.
  • Because most DFW homes have “Popcorn” Textured Ceilings, you will need to add caulk to seal the new fixture to the ceiling.  Put the caulk around the hole in the ceiling – not- at the edge of the new fixture’s lip.***  Also ensure the new fixture will cover the caulk.
    • Note: *** Caulking as instructed ensures that if the fixture ever must be removed, the damage to the popcorn texture will be covered by the lip of the new fixture once reinstalled.

 

4. Insulation

measuring insulation level in attic

Image Source: ShutterStock

Common Texas Homes Insulation Levels & Those Required By Building-Code Over Time

                          Attic Insulation                              Wall Insulation

      • 1950’s: none                                     none
      • 1965-1970: R-13 (2″ BATT)         R-6 (2″ BATT)
      • 1970’s: R-19 (6″ BATT)                 R-6  (2″ BATT)     *3
      • 1980’s: R-30 (9″ Blown)               R-13 (3.5″ BATT) *4
      • 2014:    R-38 (15″ Blown)              R-15                         *5
      • *3 Source: https://snuggpro.com/blog/item/many-homes-built-prior-to-1980-were-built-without-insulation-in-the-walls
      • *4 Source: https://www.jlconline.com/how-to/insulation-code-change_o
      • *5 As required by the 2012 Edition of the International Building Code (IBC)

Does Your Attic Floor Have The Insulation Depth / Thickness Required For At Least R-38?

 

15″ of Blown Insulation is required for R-38 (less thickness if a BATT of insulation is at the bottom).    If you have less than R-38 insulation, it’s likely more cost-effective to spend the additional money (to upgrade from Standard Efficiency To High Efficiency furnace) on insulation instead.

The cost to insulate your attic to at least R-38 will likely be similar to the High Efficiency Furnace Upgrade charge.  Both a High-E furnace and attic insulation will lower heating costs.  Attic insulate will also lower cooling costs.

To Learn About Attic Insulation, Click Here: AlsPlumbing.com Lower Heating Costs With Attic Insulation

 

For Additional Ways To Lower Heating Cost (w/o replacing furnace) Click Below:

 AlsPlumbing.com Lower Heating Costs – 20 Uncommon Ways.

 

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Al’s Plumbing, Heating & A/C in Plano, Texas 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).

Al’s also 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 is near your home in northeast Dallas, Richrdson, and Garland.  We service all homes in southern Collin and Denton Counties with no travel charges.

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.