This Is Part 3 Of Our 4-Part Article

Click Here To Read Part 1:  AlsPlumbing.com Heat Pumps Part 1 of 4

Click Here To Read Part 2: AlsPlumbing.com Heat Pumps Part 2 of 4

The article is about Heat Pump’s normal operation noises — and noises that may indicate the Heat Pump needs to be serviced.    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 County, TX; and Southern Denton County, TX with no additional 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.

Heat Pump Normal Operation Noises

Normal Operation — Recurring Noises

Most recurring noises are normal operation. 

In cooling mode — heat pumps work identically to central a/c.

In heating-mode — during the Defrost-Cycle, Heat Pumps make strange & loud noises.

Heat Pump Sounds Often Heard.  These noises are normal — and no service is needed.

• Rattle: make sure the access-panel is tightly screwed into place.  If the rattle continues, call for service.

Click Here For Rattling Access-Panel: Loose Access-Panel Rattle

• The Outdoor Unit’s Compressor gets notably louder during a Heat Pump Defrost-Cycle.

Click To Hear Heat Pump During Heating  &  During Defrosting: Heat Pump Noises During Defrost-Cycle (at Time: 0:16 / 1:26)

Click Below To Hear Trane / American Standard Brands Heat Pump During Defrosting & Heating:

Trane / American Standard Brands Heat Pump During Defrost & Heating Cycles

Note:  In the video just above, you can see the frost melting on the coils and steam rising from the outside unit during a Defrost-Cycle.

• “Air Brakes” sound.  Near the beginning & end of a heat pump defrost-cycle — a sound is heard that’s similar to a large truck’s “air brakes” (a loud “pssssssst”) happens.  This is the sound of the Refrigerant Reversing-Valve (reversing the refrigerant’s flow).

Here the Refrigerant Reversing-Valve Noise At This Link:    “Air Brakes” Heat Pump Sound (at Time 0:38 / 1.28)

• “Labored” sound from outside unit while running. The “labored” sound is likely normal if the heat pump has done it since it was new.  If the Heat Pump started making the sound later — call for service.

Here A “Labored” Sound At This Link:   Heat Pump “Labored” Noise” *

• There is frequently a low volume, buzzing noise coming from the outdoor unit even when it’s not running.  This is usually a normal sound from a power-transformer.

Heat Pump Noises That May Indicate That Repair Is Required

Heat Pump Problems — If You Hear Any Of These Noises Coming From The Outdoor Unit:

•  Loud Humming Or Buzzing:  This may indicate the Heat Pump is trying to run, but can’t start running.

• The compressor is an electric motor that requires more electricity to start running than to keep running.
• The extra power is supplied by a “Capacitor“.  It’s a rechargeable battery that “jump starts” the compressor.  Over time, capacitors wear out and must be replaced.
• If the capacitor does not provide the needed electricity “jolt” — the compressor can’t start running.
• If this is occurring — turn the heat pump off and call for service.   The compressor can become damaged while trying to run in this condition.

• Heat Pump Problems: Hissing.  This may indicate a refrigerant leak.   This sound is not the same as the brief “Air Brakes” sound generated by the Refrigerant Reversing-Valve.

• Heat Pump Problems: Clanking Or Banging.  This often means a component inside the heat pump is hitting something.  This may be due to the fan blade becoming bent.

Click Here To Hear A Clanking Noise From HVAC Outside Unit):

Clanking Noise From HVAC Outdoor Unit

• Heat Pump Problems:  High-Pitched, Scream-Like Noises.  They may indicate outside unit’s compressor has refrigerant-pressurization issues.

Click Here To Hear A High Pitched Squeal From HVAC Outside Unit (from an a/c in this video):

High Pitched Squealing From HVAC Outside Unit

• Heat Pump Problems:  Grinding / Shrieking:   These sounds point toward problems with either the compressor or fan motor.  Over time, motors gather dirt along their bearings, and that can lead to the shrieking noise.  Grinding sounds usually mean too much stress on the mechanical parts of a motor due to lack of lubrication or dirty components.

Click Here To Hear A Shrieking Noise (from a/c in this video): Shrieking Noise From HVAC Outdoor Unit

Heat Pump Normal Operation Noises — While Heating

And

Heat Pump Normal Operation Noises — During Defrost Cycle

Al’s Sells Heat Pumps from American Standard, Ameristar, Coleman HVAC & Goodman 

1. Normal Operating Noise Levels (not during defrost cycle) as stated by American Standard:

• Platinum Series: 59-72 db.   SEER: 18-20  This series has as a Variable-Speed Compressor that generates different noise levels depending on how fast the compressor is running to meet cooling or heating demand.

• Gold Series: low 70’s db         SEER: 17         This series has a 2-Stage Compressor that generates different noise levels based on whether it’s in low-stage or high-stage.

• Silver Series: mid 70’s db     SEER: 14-16    This series has a Single-Stage Compressor.  The noise level will always be the same when it’s running.

    2. Normal Operating Noise Level (not during defrost cycle) as stated by Goodman:

• Goodman DSZC18   72-74 db  SEER: 18

   3.  Hear the most noise made during A Heat Pump Defrost-Cycle:

• Click to hear an American Standard SEER-15 Heat Pump with Climatuff brand compressor —during the defrost cycle:  American Standard / Trane ClimaTuff Compressor Heat Pump while defrosting

• Click to hear a Goodman SEER-14 Heat Pump with Copeland brand compressor — during the defrost cycle: Goodman Heat Pump (Copeland Compressor) during defrosting.

Click Here To Read The ClimaTuff® Compressor Brochure: Climatuff® Compressor Brochure

   4. Why is the noise level lower on American Standard Heat Pumps — as compared to Heat Pumps with Copeland® Brand Compressors?

• American Standard & Trane (made by the same company) use their own (self-designed & self-manufactured) Climatuff ® brand compressors.  Nearly all other Heat Pump brands use Copland brand compressors.

• American Standard & Trane have all-aluminum Spine Fin™ Coils in their outside unit.  The coils have thousands of small fins projecting from them.  Additionally — aluminum doesn’t rust.
• The purpose of the Spines is to make the coil more efficient — as the Spines provide more surface for air to flow through.
• Another benefit of Spine Fin™ Coils is they provide more surface that helps block noise.

• No other Heat Pump brands have Spine Fin™ Coils.

Click Here To See An American Standard / Trane Outdoor Unit Spin Fin™ Coil: Spin Fin™ Coil

Click Here To View A YouTube Video About Spine Fin Coils: YouTube Video: Spin Fin™ Coils

Click Here To See A Typical Heat Pump Outdoor Unit Coil: Typical Heat Pump Outdoor Unit Coil.

 ** Source: http://www.trane.com/commercial/north-america/us/en/products-systems/equipment/chillers.html

American Standard AccuComfort Platinum 19 Variable-Speed Heat Pump:

This was the quietest Heat Pump available at the time this article was written.** 

The American Standard AccuComfort Platinum 19 Variable-Speed Heat Pump:

• Cooling SEER-19.5.  The minimum or DFW is SEER-14.   SEER stands for: “Seasonal Energy Efficiency Rating” — a standardized efficiency rating system.

• Heating HSPF–up to 11.5.   The minimum for Dallas is HSPF-8.7.    HSPF stands for: “Heating Seasonal Performance Factor” — a standardized efficiency rating system.

• **  Ultra-quiet performance — with sound levels of 43 to 57 dB.    Most heat pumps create around 70 dB while in Heating Mode.

• Defrosts only when needed.   Some brands defrost on a recurring time-schedule — whether they need to or not.

• Includes the Duratuff Compressor.  A proprietary design available only in American Standard & Trane HVAC Systems.  American Standard & Trane brands are made by the same company.

• TruComfort™ variable speed system provides 500-700 different compressor speeds.

• When paired an American Standard AccuLink™ zoning system — you can control temperature on a room-by-room basis — without sacrificing efficiency.   This feature is available because of the outdoor unit’s variable-speed compressor & the furnace’s variable-speed blower fan.  When rooms are not being heated/cooled — the compressor simply slows down to adjust to less area being heated/cooled.  Motorized dampers can be installed within new or existing ductwork — to redirect airflow to only where it’s wanted.

For A Brochure On The American Standard AccuComfort™ Platinum 19 Heat Pump — Copy The Link Below Into Your Internet Browser:

https://www.americanstandardair.com/content/dam/americanstandarair/brochure/heatpumps/10-1190-07%20AS%20Variable%20Speed%20Cons%20Brochure.pdf

The American Standard AccuLink™ Zoning System

Most homes’ temperatures differ from one room to the next.  Causes of these temperature fluctuations may be due to:

• time of day or night
• sunlight exposure
• room occupancy  (some rooms are seldom used)
• room function (such as kitchen and laundry room)
• other factors unique to an individual home.
• wind-chill during winter (affecting rooms the wind is blowing on)

The American Standard AccuLink™ Zoning System installs electrically-operated dampers on many (or all) ducts.  This allows the thermostat in each room to open or close the room’s damper as needed.  Combined with a Variable-Speed HVAC System — the outdoor unit and furnace blower-fan speeds up / slows down based on the number of dampers that are open.  A variable-speed HVAC System adjusts itself to hundreds of different speeds — to align with the current heating or cooling needs of the home at any given time.   The System adjusts continuously as heating or cooling demand changes.

For A Brochure On The American Standard AccuLink™ Zoning System — Copy The Link Below Into Your Internet Browser:

https://www.americanstandardair.com/content/dam/americanstandarair/15-4156-03_HR.pdf

Ways To Reduce Normal Operation Noises With A Heat Pump

If your heat pump problems are limited to it making too much noise, there are products that can help.

Noise levels in db at 3.3 feet (40 inches).  Most Heat Pumps operate in heating or cooling modes in the mid 70’s db.   They get louder during Defrost-Cycle.

• +1o dB sounds twice as loud to your ears. 

• 50 dB – Quiet conversation at home
• 60 dB – Conversation at a restaurant
• 70 dB –  vacuum cleaner
• 80 dB –  garbage disposal

NOTE: Before you add sound-abatement products, check to ensure the Heat Pump’s access-panel on the outside unit is screwed in tight.  Heat Pumps vibrate, and this can loosen screws on this panel.  Normal vibration can cause loose access panels to rattle.

Sound Fence.   There are many brands and types of sound-reducing fencing.  We show this one because all you must do is place it around the outside unit (minimum of 2 feet away for air flow).  Note: Many companies sell acoustic-panels, but many require the user to build a structure to support them.

• The manufacturer states this product “Uses the same noise reduction technology used in Sound-Studios.”
• Hear the product’s noise-reducing ability in a YouTube Video with this link: Quiet Fence Video Demonstrating Effectiveness
• In the video, this product reduced noise from 73db (without fence) down to 64db (with fence in place).
• To the human ear — a -9 db reduction reduces the noise by nearly half.

Click Here To Hear A Loose Access Panel Rattling:    Loose Access-Panel Rattle

Compressor-Blanket.   Some Heat Pump or A/C compressors are loud from the day they are new.  Others may become loud as they age due to normal wear.  Neither of these is due to heat pump problems.   A Compressor-Blanket is designed to reduce the amount of noise heard from the compressor.  It is wrapped around the compressor and held into place with velcro straps.   As stated by one manufacturer: “Brinmar Sound Blankets reduce compressor noise by a substantial 40% reduction in noise.”

• Note:  Some a/c brands include a compressor blanket when new.  Check to see if your outdoor unit already has one.
• Note:  This product claims to produce a 40%+ decrease in noise (4–5 db) — this equates to a -25% noise decrease.  The sound fence above showed nearly a -50% noise decrease.
• Note:  This is not an endorsement of this product.  We cannot endorse any specific brand of a/c compressor blanket because we don’t have first-hand knowledge of them.

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

Rubber Anti-Vibration Pads.   If the noise is due to the Heat Pump vibrating, the outside unit can be lifted (by a professional) — and these pads placed under its feet to absorb much of the vibration.  The pads absorb vibration and reduce noise.

Note: Vibration-Pads help only with noise generated by vibrations.   If the rattle is new, or has become louder — check to ensure the Access-Panel screws are tight, as vibrations can loosen them. Vibration-Pads won’t help reduce noise generated by the Heat Pump’s compressor.  The compressor is the source of the majority of noise generated by the outside unit.

Here is the YouTube Video shown earlier: Rattle Caused By Loose Access-Panel On Heat Pump

Note:  This is not an endorsement of this product.  Al’s does not endorse any specific brand of anti-vibration pad, only because we don’t have knowledge of all brands available.

Click On Photo To: View Product, See Details or Purchase From Amazon.com
 Shown: Rubber Anti-Vibration Pads

Landscaping:  Adding bushes near a Heat Pump or A/C may help reduce noise.  Landscaping must be kept at least 2 feet from the outside unit to ensure enough air-flow.  A simpler and less expensive solution may be the noise fence described above.

This link takes you to a website that describes the best shrubs to use in Texas.  Texas A & M: Best Shrubs To Use In Texas

The article was about Heat Pump normal operation noises — and noises that may indicate the Heat Pump needs to be serviced.    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 County, TX; and Southern Denton County, TX with no additional 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.