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, TX; Allen, TX; and Frisco, TX.  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.

What Is A Variable-Output (Modulating) Furnace?

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With mild north Texas winters, furnaces don’t need to heat at full capacity much of the time.  During mild weather, a furnace heating at full capacity may heat the house too quickly or too much.   Then it shuts off and waits for the indoor temperature to drop 3-4 degrees before it runs again.    This can cause the house to always feel too cold or too hot — and constantly changing.  A variable-output modulating furnace will minimize these temperature swings to as little as 1/2 degree.

• A a single stage furnace is like an on/off light switch.  The on/off light switch turns on the light bulb on at its full capacity.  The switch turns the light off when you’re done.

• A variable-output modulating furnace is like a lighting dimmer switch.  A dimmer switch allows illumination from very low to maximum brightness.

Standard, single-stage furnaces have one speed.  They can’t adjust their heat output with changing temperatures.

Two-stage furnaces have a “low” & “high” speed.  This furnace turns on at 50% heat output.  If the thermostat setting is not satisfied in 5 minutes, the furnace goes to maximum heat output. These furnaces lower output when outdoor temps are milder, or while maintaining the indoor temperature.  They increase output when outdoor temps are lower and / or when the thermostat has be set several degrees warmer.

Variable-Output Modulating furnaces adjust both the flame size and blower fan speed to match every heating need.  With an efficiency rating of up to nearly 99%, these furnaces exhaust very little heat with the exhaust gases.  Modulating furnaces consume less energy because they rarely operate at full capacity.  As compared, a standard-efficiency furnace sends 20% of its heat outdoors with the exhaust.

Variable-output modulating furnaces incorporate a modulating gas valve — it allows the furnace to control the burners’ flame size with the amount of gas flowing into them.  The gas valved is paired with a variable-speed blower fan.  The slower the blower fan runs, the less noise it makes.  Running longer at lower levels allows the furnace to use less energy than standard furnaces.  It also more effectively heats with fewer temperature variations from room to room.  Because the blower fan runs more, modulating furnaces filter indoor air better.

Copy this link into your brower to see Atmos’ current gas furnace rebates: https://www.atmosenergy.com/ways-to-save/mid-tex-appliance-rebate-program

Is A Modulating Furnace The Best Choice For You?

These additional benefits come with a variable-output modulating furnace.   If these benefits are a higher priority than price, a variable-output modulating furnace furnace is likely best for you.  If price is a higher concern, a single-stage or dual-stage furnace will be less expensive.

• Maximum comfort:  This is the #1 reason to get a modulating furnace. You’ll notice a notable increased in your home’s heating comfort.  This is because a modulating furnace does not wait for room temperature to fall before cycling.  Instead, in increases / decreases its heat-output to mach current heating-demand.

• Energy savings: Modulating furnaces rarely run at full capacity.  This reduces on/off cycling periods.

• Eco-friendly: Modulating furnaces have an Annual Fuel Utilization Rate (AFUE) of up to nearly 99%).  A standard gas furnace has an AFUE rate of 80% (20% of the heat generated is sent out with the exhaust.

• Rebates: At the time this was written — Atmos Gas offered a rebate of $400 for installing a gas furnace with an efficiency of 95% or higher.

The Three Types Of Furnaces:

• Single Stage: Furnace is either on or off.  The furnace’s gas valve is either fully open or closed.   The furnace’s blower is off or running at its only speed.
• Once the temperature is 3-4 degrees below the thermostat’s setting –the furnace comes on, runs at its highest speed, then shuts off.

• Two Stage: Furnace runs at partial or full capacity based on current heating demand.
• It chooses to run at low or high based on heating demand.

• Variable-Output Modulating: Furnace matches heat-output to current heating demand.
• It heats only as much as needed.  This minimizes gas consumption.
• The gas-valve can be partially to fully open.   The volume of gas flow determines the flame size in the burners.  The larger the flame, the warmer the air coming from the ducts is.
• A  variable-speed blower speeds up or slows down as needed.

• When coupled with a variable-speed Central A/C  — the furnace’s blower runs slower during times of less cooling demand.  This prevents large swings in indoor temperature.
• When the blower is running a slower speeds — the A/C dehumidifies better.

Variable-Output Modulating Furnaces Provide These Benefits:

• The home’s temperature is more stable.  Modulating furnace maintains temperature within ½ degree.   Note: A single-stage furnace maintains temperature within 3-4 degrees.
• They use less fuel because they don’t run at full capacity unless needed.
• The blower runs more of the time, and the air is filtered more.
• The blower makes less noise when it’s running slower.

Cariable-output modulating furnace are an upgrade feature.  Variable output capability is not required, but can make for a more comfortable house that stays within 1/2 degree of the thermostat setting.  As compared, a single stage furnace allows the temperature to drop 3-4 degrees before a heating cycle begins.

If you reduce the temperature while at work or overnight — the furnace runs at full capacity until the it reaches the thermostat setting.  Then it adjusts its output downward to current heating demand.  A Modulating Furnace is paired with a Variable-Speed Central A/C or Heat Pump.  A variable-speed A/C matches the cooling demand.  In order for it to be able to do that, the furnace must also be able to adjust its blower fan speed.

Want To Know More Ways To Lower Heating Costs?   Click Here For Part-1 Of Our 3-Part Article: Lower Heating Costs Part 1 of 3

Al’s Plumbing, Heating & A/C sells American Standard, Ameristar, and Coleman HVAC.   American Standard brand offers a modulating furnace. 

Copy This Link Into Your Browser For A Brochure:American Standard Variable-Output Furnace Brochure

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, TX; Allen, TX; and Frisco, TX.  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