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This Is Part 3 Of A 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

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 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.american standard platinum gold silver series hvac

Heat Pump Problems — Noises

Heat Pump Problems — Normal Recurring Noises

Heat pump problems can become evident with strange noises.  Most recurring sounds are part of normal operation,  though they sometimes make owners think they have heat pump problems.  Heat Pumps make strange and/or loud noises mostly during the Defrost-Cycle (that a central a/c does not make).

Heat Pump Sounds Heard Most Often:    Note: None of these are due to heat pump problems. 

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

Here The Loose Access-Panel Rattling At This Link:    Loose Access-Panel Rattle

  • Compressor gets notably louder during a Heat Pump Defrost-Cycle.

Hear Heat Pump During Defrosting At This Link:   Heat Pump Noises During Defrost-Cycle

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 of the heat pump defrost-cycle, often a sound is heard that’s similar to a large truck’s “air brakes” (a loud “pssssssst”).  The sound usually lasts for a couple of seconds.  The sound is the Refrigerant Reversing-Valve reversing the refrigerant’s flow.

Here the Reversing-Valve Noise At This Link:    “Air Brakes” Sound From Heat Pump When Reversing-Valve Changes

  • “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 it has started making the sound later, call for service.

Here The “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 Problems — Noises Requiring Repair

If you hear any of these noises coming from the outdoor unit:

  • Heat Pump Problems: Loud Humming Or Buzzing:  This often indicates the Heat Pump is trying to operate, but is unable to.  This often means it’s unable to start running.  The compressor is a 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 “jolt” — electricity may be entering a compressor that was unable to start running.
  • Heat Pump Problems:  Hissing.  This often indicates a refrigerant leak.   This sound is not the same as the “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 can be often be due to the fan blade becoming bent.

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

Clanking Noise From HVAC Outdoor Unit

  • Heat Pump Problems:  High-Pitched, Scream-Like Noises.  They can indicate (outside unit) compressor 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

Normal Noise-Level During Heating Mode

And Insight Into Normal Noise-Levels 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.  HOWEVER,  the most noise is made during A Heat Pump Defrost-Cycle:

   4. Why is the noise level lower on American Standard than Heat Pumps with Copeland Brand Compressor?

More than half of the large buildings in the world today are conditioned by Trane. **   American Standard & Trane (made by the same company) use their own (self-designed & self manufactured) compressors.  Nearly all other brands use Copland brand compressors.

Copeland compressors are used in value-priced HVAC Brands.  In order to be able to offer a lower price, less expensive components may be used.  That’s not to say Copeland compressors are not good quality, only that they make notably more noise during a Heat Pump defrost-cycle.

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

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

 

Ways To Help Reduce Noise From An Existing Heat Pump Or A/C

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

Noise levels in db.  Note: 1 meter = 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.

  • 50 dB (1/4th as loud as 70 dB) – Quiet conversation at home
  • 60 dB (half as loud as 70 dB) – Conversation at a restaurant
  • 70 dB (sounds twice as loud (to your ears) as 60 db) –  vacuum cleaner
  • 80 dB (sounds twice as loud as 70 dB) –  garbage disposal

Note 1: Each additional +10db in noise-level sounds twice as loud to your ears.

Note 2: The frequency of the noise (Example: low rumble versus high squeal) will make it seem louder to persons who are more sensitive to that frequency.

 

Do You Own A Noisy Heat Pump? These Products Can Help.

Different brands and models of Heat Pumps will produce various levels of noise.  As described above, most recurring noises are not indicative of heat pump problems.

If you are considering replacing your existing Heat Pump mostly because of the noise it makes, these products can be used to reduce the amount of noise heard (by absorbing the noises).   They can be equally worthwhile if you choose a brand of new Heat Pump that makes more noise while defrosting.   The products shown likely are the most effective because they are specifically designed for HVAC outside units.

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.”
  • In the video, this product reduced noise from 73db (without fence) to 64db (with fence in place).   A -9 db reduction sounds to the human ear like nearly cutting the noise in half.
  • Hear the product’s noise-reducing ability in a YouTube Video with this link: Quiet Fence Video Demonstrating Effectiveness

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.  The same vibration cause loose access panels to rattle when the outside unit is running.

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.”

Click Here To Hear Noise Reduction Provided By A Compressor Sound-Blanket: 4-5 Db Sound reduction by Compressor Blanket

  • Note:  Some a/c brands include the compressor blanket when new.  Check to see if your unit already has one.
  • Note:  This product claims to produce a 40%+ decrease in noise -4-5 db).  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 a lot of the vibration.  As the pads absorb vibration, they 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

Ever-Green Landscaping:  Adding evergreen bushes near a Heat Pump or A/C may help reduce noise.  Any landscaping must be kept at least 2 feet from the outside unit to ensure enough air-flow.  A simpler and much less entailed solution is 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 Shurbs To Use In Texas

We have provided a brochure for American Standard / Trane Climatuff Compresors which gives many details about the compressors.  It also explains (according to the manufacturer) why ClimaTuff compressors are superior.

 

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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 Plano, Allen, and Frisco.  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.

This Article Is Continued In Part 4 Of 4