I had the same concern with my 2 ton 25VNA024A003 and took a video to show my carrier dealer. That said they thought it was normal and said that is why they are instructed not to install the outside unit near any bedrooms. Ours is fairly close to the bedroom and can be heard inside but we have enough insulation that it cuts out most of the noise and is less annoying than the neighbors dog! Lol in a way it is comforting to hear others have the same noise.

Thank you for your reply! You don't know how much I appreciate your feedback. I thought I was the only one having this annoying problem.

My installer told me that this unit was whisper quiet and that I should have no problems so we installed it close to our bedrooms. It certainly is whisper quiet when heating in warmer outdoor temperatures but when it gets really cold (below freezing), the heat pump gets really loud. Now I think about it, it sounds like inside of a flying airplane.

One thing the dealer did to reduce my noise level was to remove the refrigerant as it was overcharged. When it was overcharged, it was REALLY LOUD!

Is there some way I could see your video?

I wish I could figure out how to post my video of how mine sounded but it was louder than your sound clip. But it is whisper quite all the time except heating below freezing than it is louder than other heat pumps I have heard.

I have the same noise! we have had our 3 ton unit for 2 years now. It is super quiet in summer, but when it gets below 30 or so it gets louder as it gets colder...top of unit ices up in freezing rain to choke off air flow, defrost cycle
never seems to defrost all frost and ice, install company sent out techs to look at it but was not cold enough to hear the noise or see heavy frost, second one never saw a 25vna and had no manuals because it was rare and brand new!

I recently visited a Greenspeed installation in my area. The temperature at the time was about 26F. The HP was operating and was quite quiet. My wife remarked that the fan was louder than the compressor, to give you an idea. This client has complained that it was quite noisy at times. I have not experienced this yet. I will have to revisit again when the temperature drops to -4F.

What we do here in the Montreal area has been to recommend up sizing the Greenspeed series by 1-ton due to the extreme cold and noise factors. I know that the âÂÂManual J-ersâ will be all aghast but thatâÂÂs what it is and thatâÂÂs what weâÂÂve been doing. As well the client will also have greater energy savings in cold climate by up sizing 1-ton. This doesnâÂÂt mean that the smaller size wonâÂÂt do the job but this has been CarrierâÂÂs recommendation and ours as well.

SR

thanks for the reply madirv. If you have improper defrost and constant icing, you may want to have the installer recheck your refrigerant levels. Mine completely iced up and was due to low refrigerant.

fsq4cw - My 4 ton is quiet enough when operating below 50%. It's only when the compressor revs up above. If you do go out again, check out the system at 100% and see if you hear the loud compressor noise.

thanks for the reply madirv. If you have improper defrost and constant icing, you may want to have the installer recheck your refrigerant levels. Mine completely iced up and was due to low refrigerant.

fsq4cw - My 4 ton is quiet enough when operating below 50%. It's only when the compressor revs up above. If you do go out again, check out the system at 100% and see if you hear the loud compressor noise.

âÂÂIf you do go out again, check out the system at 100% and see if you hear the loud compressor noise.âÂÂ

ThatâÂÂs why I mentioned that I would have to revisit when the temperature is more like -4F.

SR

gsq4cw have you check out the unit at -4F?
Since I am looking for this unit too.
Right now, I do not know if I will be better off with the 25VNA or a geothermal heating system, since I do not like to have a noisy system.

This post was edited by MickyNaso on Wed, May 14, 14 at 14:37

Unfortunately, this client had many issues regarding their 4-ton Greenspeed, noise being only one. Carrier did agree to replace the unit under warranty but I will only know next winter whether the noise issue was fully resolved.

I will reserve my final judgment on Greenspeed until I can audit this unitâÂÂs performance for at least 1-year. In principal I fundamentally believe in the Greenspeed technology, as itâÂÂs not new. However, at this time I personally would put my money into geothermal.

IMPO

SR

I think the greenspeed system needs more refinement. I would not doubt that a mix of mechanical and control/ monitoring system changes need to be made and I think eventually all manufacturers will have models for extreme cold.

Geothermal has my vote until then.

Greenspeed is pretty much geothermal without the ground loop. Most of the best geothermal systems are run by variable speed inverters, like the Waterfurnace 7 and Climatemaster Trilogy.

I'm confident enough real-world and field testing have been done in the past three years. The real problem is a lack of understanding and appreciation of these systems. I asked all Carrier dealers questions from the Greenspeed installation manual and only one seemed to have already read it.

Most HVAC dealers think of heating and cooling systems as nothing but glorified on/off switches. Only a few have a true intellectual hunger regarding newer tech.

I wouldn't be surprised if some of the noise comes from an improper installation, probably regarding the muffler on the vapor line and the proper amount of lineset.

This post was edited by bsmith on Wed, May 21, 14 at 1:14

Many may think or âÂÂwishâ that Greenspeed is geothermal without the ground loop but sadly it is not. Only geothermal is geothermal.

The 25VNA I referred to in my previous post was installed by people that I can assure you are at the top of their game. Carrier might not have sprung for the replacement if it was just poorly installed. I am sold on the concept of variable speed compressors but I have doubts about Greenspeed for our cold climate at this time, IâÂÂm sorry to say.

Several of the âÂÂlatestâ geothermal units do have variable speed compressors. The âÂÂbestâ geothermal heat pumps are those installations providing efficient comfort without ANY problems for many years, even if their COP is not as high as the latest 'theoretical' figures.

IMO

SR

Those many who know or wish also understand the difference between regular geothermal and direct geothermal. A direct geothermal system uses refrigerant and copper piping and isn't much different than the Greenspeed less the ground loop.

Inverter systems have actually been around more than a decade and really aren't that new. In fact, many countries are already starting to move toward linear compressors, which are pound-for-pound superior to variable speed inverters. To say the US is far behind the world would be an understatement.

This post was edited by bsmith on Tue, May 27, 14 at 1:01

There IS a HUGE difference between Greenspeed and DX unless all youâÂÂre referring to is that an air-source HP has its âÂÂcoilâ wrapped around the perimeter of the HP whereas a DX system has its coil buried within the constant temperature of the ground.

SR

I'm just trying to figure out where the Greenspeed needs refinement over current geothermal when they both use inverter tech with brushless DC motors, which is fine if you are trying to justify your preference. In fact, Carrier invented the modern AC 100+ years ago and Emerson (Copeland) has been is business 100+ years making more scrolls than anyone else in the world, period. :)

Also, I'm trying to figure out what's causing the noise in some of these installs, especially the unusual ones where it truly is the scroll and the lineset is properly isolated from the system. Perhaps Carrier's suggestion is golden about sizing up one ton in heating regions or the scrolls passed QC when they should not have.

In fact, in heating climates these VS scrolls work BEST and most efficient when they are way less than 100% of load, so Greenspeed sizing truly needs special consideration. Although the 2 ton can be easily changed into a 3 ton, and the 4-ton can easily be changed into a 5-ton. ;)

Hi Everyone,

Thanks for these postings, they really help the "ordinary" guy like me.

We bought a 25VNA048 system end of june 2014. Summer was fantastic and a lot quieter than our previous 15 years old Carrier system.

2 days ago, it was about 5F here at night in the Montreal region. The HP kept us awake all night.

It is incredible how low temperature and high rev affects noise of this unit. My old thing was noisy but remained constant. This new one noise level is variable and that makes it worst.

Even at 5F, this 4T unit has capacity to spare for our 2900 sqf house, it ran at 50-60% by periods most of that cold day and was off frequently. Temperature Inside is stable at 73/74F all day, no problem.

Problem is that after a defrost cycle, the unit climbs to 100% for a while and then all hell breaks loose. Same situation with 15F or more, still a bit of noise but dramatically less even at 100%

The muffler is installed but I do not know if it is installed correctly, that is the only doubt.

You should here this thing at 5F out when at 100%! Anyone thinking of buying this would turn around fast. Below 5F it goes to electric, costs a bundle but we can sleep.

Thank you in advance for any new thoughts on the subject.

Really appreciated!

MB

Another noisy Greenspeed in a cold climate, what a surprise!

Almost a year ago to the very day - in this very thread, I suggested up-sizing Greenspeed by 1-ton for this very reason in this very season!

MB, you probably needed a 5-ton 25VNA060 not a 4-ton 25VNA048. Sadly, thatâÂÂs about the only âÂÂfixâ that will still maintain high efficiency. You would have achieved even higher efficiency with the 25VNA060 HP & FEANB006000 Fan Coil combination, 18-SEER & 10.87-HSPF for zone 5, which youâÂÂre in, verses 17.5-SEER & 9.56-HSPF, if you have the FE4ANF005000 Fan Coil unit (for zone 5).

If you already do have the FE4ANB006000 Fan Coil unit, youâÂÂre already at 18.3-SEER & 10.87-HSPF (for zone 5). Those ratings are all âÂÂUp Toâ whatever SEER & HSPF.

The pity is that balanced against the cost of a 5-ton Greenspeed system, a 4-ton geothermal system might have looked pretty attractive when considering all the government rebates that were available and that have just expired!

I donâÂÂt know how you were advised - I just hope it wasnâÂÂt me!

IMPO

SR

Thanks for the response SR.

The number written on the fan coil Inside is FE4ANB006L00...

We had a previous 4T Carrier HP with a mismatched Ruud electrical furnace which was more than sufficient enough so we renewed with the same capacity.

At 5F outside which is just on the trigger point to go to full electric, the system runs on average at 50 to 70% capacity maintaining Inside temp at 73/74 and with variable periods where the HP is off entirely. We are set in electric heat lockout above 5F. This makes me beleive that we have more than enough capacity.

I am just wondering if a 5T unit would make that much difference on noise since even a 5T unit would rev up to 100% from time to time, in the morning for example during recovery, after defrost cycles, and so on, It would obviously run at lower rev on average but the peeks above 80% are what is causing all that jazz and keeping us awake :-)

Our installer is coming up (hopefully) next week acompanied by a Carrier rep a day when outside temp is around 5 to 10F. Will see what they have to say.

Should have read your posts 6 months ago, sad.

Thanks again.

MB

My best advice to you, MBCan, is that when the installer shows up with the Carrier rep, take a picture of the highest noise level reading on the sound pressure level meter, in dBs, of what was observed, if this measurement is taken, so that you have a visual record that can be produced and used if needed.

I would also suggest that the 4-ton unit be swapped out for the 5-ton Greenspeed while offering the pay the difference between the two HPs. You already have the appropriate size fan coil unit. I ALWAYS advise Greenspeed clients to purchase the 10-year labor warranty as well. That way they are covered for all eventualities and have leverage with Carrier and the dealer. In fact if you had the extended labor warranty and wanted to change the HP for the 5-ton, I know that quietly, behind the scene, the dealer would likely also be âÂÂtwistingâ CarrierâÂÂs arm in that direction because the dealer KNOWS that they will be TORTURED by you over the next 10-years with little or no benefit to them. No 10-year warranty means the dealer âÂÂdiscomfortâ is about 9-years less.

I would not use any set backs or âÂÂSmart RecoveriesâÂÂ; just set your desired indoor temperature and let the system do its thing - no âÂÂlock outsâ - nothing! The backup is already staged and will be as efficient as possible regardless of the mode.

Your HP should be operating down to about -25C or why else did you buy a Greenspeed!

Sorry if all this sounds a little discouraging but I would like others living in cold climates to understand the ramifications of installing Greenspeed and benefit from my cold climate experience and expertise, that some do pay for just to hear.

IMPO

SR