What causes this racket?

>http://www.youtube.com/watch?v=9gfnmVB5q3c&NR=1
>I have a Goodman GSZ (installed Nov) that has started making the same
>noise during defrost. There is also a neighbor with a Frigidaire that
>makes a similar noise during defrost. He had an HVAC tech come and
>tell him that is the way these things work. That was a quick 100
>bucks.
>I am waiting for a HVAC tech to come but if he also tells me this is
>"normal" the world will have one less HVAC tech ;)
>I paid $540 for commisioning the unit - 3 hours labour. The $40 was
>for a filter/drier. After checking I've found that there was a drier
>already installed so this was a waste. BTW, records show 6.6 ounces of
>R410 was added for tubing but none for extra filter.
>The unit ran fairly quiet for about two months until the temp went
>down to 20F. Should there be a crankcase heater?
>Frosting rarely completely covers coils - not much icing on bottom
>sections. Defrost setting at 30 minutes.
>How well do the sound blankets on the compressor work?
>Looking forward to the replies - good, bad, funny AND ugly......

>>http://www.youtube.com/watch?v=9gfnmVB5q3c&NR=1
>>I have a Goodman GSZ (installed Nov) that has started making the same
>>noise during defrost. There is also a neighbor with a Frigidaire that
>>makes a similar noise during defrost. He had an HVAC tech come and
>>tell him that is the way these things work. That was a quick 100
>>bucks.
>>I am waiting for a HVAC tech to come but if he also tells me this is
>>"normal" the world will have one less HVAC tech ;)
>>I paid $540 for commisioning the unit - 3 hours labour. The $40 was
>>for a filter/drier. After checking I've found that there was a drier
>>already installed so this was a waste. BTW, records show 6.6 ounces of
>>R410 was added for tubing but none for extra filter.
>>The unit ran fairly quiet for about two months until the temp went
>>down to 20F. Should there be a crankcase heater?
>>Frosting rarely completely covers coils - not much icing on bottom
>>sections. Defrost setting at 30 minutes.
>>How well do the sound blankets on the compressor work?
>>Looking forward to the replies - good, bad, funny AND ugly......

> As there were no replies to this, I'll try to answer it myself.
> (still awaiting the (new) HVAC tech to come and perform his magic.)
> In the meantime, I installed a crankcase heater and sound blanket and
> found that the accumulator was rattling on startup due to missing nut
> on mounting bolt. This caused the sounds to be exacerbated.
> I think the problem is scroll compressor slugging on foam created by
> insufficient refrigerant or migration.
> Original charge was to be by weight.
> Factory charge: 35.14 oz
> Extra line charge: 6 oz
> Missing charge for unneeded filter: approx 6 oz
> I checked refrigerant charge using the hot gas method (I'm a retired
> industrial instrumentation tech so this was no big deal) and found a
> temperature rise of 119 on the hot gas line.
> I also ran the unit on a cold, humid day for an extended period and
> found VERY distinct frost banding on bottoms of coil sections. This
> unit is at my mother's house so I did not find out about problems till
> recently so I cannot say when it started. The low refrigerant may also
> be caused by leak in system. If so, I'll be pretty pissed off if it's
> in one of the installer's connections!
> I called the owner of the original heating/HVAC company and he tried
> to bullshit me. I should have recorded his dumb comments as he tried
> to explain the above and say it's "normal". He would not allow me to
> speak directly to the tech. He wants another $500 to remove the filter
> and adjust refrigerant. From his comments, I figure he is an old
> heating dude that got into the HVAC business by hiring an HVAC tech
> and doesn't know much himself.
> I had two quotes for original installation which entailed brazing
> connecting refrigerant tubing, adding appropriate amount of
> refrigerant and checking system operation. Electrical and mechanical
> installation was already done. Unit was running on aux heat and
> airflow checked using measured line voltage and current of strip
> heater in conjunction with temp probes. (756 CFM at medium fan speed
> for 2 Ton unit)
> The two quotes were $500 and $350. I took the higher because I wanted
> a good job done. Go figure....
> I have expanded heating data charts (ambient from 65 to -10) for
> installed split-system to make life easier for tech. BTW, all this
> information (including fact that filter was already installed) was
> available for original tech but he just thumbed through it and
> proceeded to do his job. I trusted him. Now I wonder if he
> contaminated the system during install.
> Will post results from new HVAC tech when he finishes.

>>>http://www.youtube.com/watch?v=9gfnmVB5q3c&NR=1
>>>I have a Goodman GSZ (installed Nov) that has started making the same
>>>noise during defrost. There is also a neighbor with a Frigidaire that
>>>makes a similar noise during defrost. He had an HVAC tech come and
>>>tell him that is the way these things work. That was a quick 100
>>>bucks.
>>>I am waiting for a HVAC tech to come but if he also tells me this is
>>>"normal" the world will have one less HVAC tech ;)
>>>I paid $540 for commisioning the unit - 3 hours labour. The $40 was
>>>for a filter/drier. After checking I've found that there was a drier
>>>already installed so this was a waste. BTW, records show 6.6 ounces of
>>>R410 was added for tubing but none for extra filter.
>>>The unit ran fairly quiet for about two months until the temp went
>>>down to 20F. Should there be a crankcase heater?
>>>Frosting rarely completely covers coils - not much icing on bottom
>>>sections. Defrost setting at 30 minutes.
>>>How well do the sound blankets on the compressor work?
>>>Looking forward to the replies - good, bad, funny AND ugly......

>> As there were no replies to this, I'll try to answer it myself.
>> (still awaiting the (new) HVAC tech to come and perform his magic.)
>> In the meantime, I installed a crankcase heater and sound blanket and
>> found that the accumulator was rattling on startup due to missing nut
>> on mounting bolt. This caused the sounds to be exacerbated.
>> I think the problem is scroll compressor slugging on foam created by
>> insufficient refrigerant or migration.
>> Original charge was to be by weight.
>> Factory charge: 35.14 oz
>> Extra line charge: 6 oz
>> Missing charge for unneeded filter: approx 6 oz
>> I checked refrigerant charge using the hot gas method (I'm a retired
>> industrial instrumentation tech so this was no big deal) and found a
>> temperature rise of 119 on the hot gas line.
>> I also ran the unit on a cold, humid day for an extended period and
>> found VERY distinct frost banding on bottoms of coil sections. This
>> unit is at my mother's house so I did not find out about problems till
>> recently so I cannot say when it started. The low refrigerant may also
>> be caused by leak in system. If so, I'll be pretty pissed off if it's
>> in one of the installer's connections!
>> I called the owner of the original heating/HVAC company and he tried
>> to bullshit me. I should have recorded his dumb comments as he tried
>> to explain the above and say it's "normal". He would not allow me to
>> speak directly to the tech. He wants another $500 to remove the filter
>> and adjust refrigerant. From his comments, I figure he is an old
>> heating dude that got into the HVAC business by hiring an HVAC tech
>> and doesn't know much himself.
>> I had two quotes for original installation which entailed brazing
>> connecting refrigerant tubing, adding appropriate amount of
>> refrigerant and checking system operation. Electrical and mechanical
>> installation was already done. Unit was running on aux heat and
>> airflow checked using measured line voltage and current of strip
>> heater in conjunction with temp probes. (756 CFM at medium fan speed
>> for 2 Ton unit)
>> The two quotes were $500 and $350. I took the higher because I wanted
>> a good job done. Go figure....
>> I have expanded heating data charts (ambient from 65 to -10) for
>> installed split-system to make life easier for tech. BTW, all this
>> information (including fact that filter was already installed) was
>> available for original tech but he just thumbed through it and
>> proceeded to do his job. I trusted him. Now I wonder if he
>> contaminated the system during install.
>> Will post results from new HVAC tech when he finishes.

>Goodman equipment is a half step above Intertherm mobile home junk. Consumer
>Reports doesn't even rate Goodman because there are so many problems because
>of internet sales and lowest bidder installs.

>Did the tech even pull a
>vacuum on the system before charging?

> Did he even own a micron gage, let
>alone how to use it??

> or... did he just let the vacuum pump run for 15 or 20
>minutes and call it good??

> BTW... 30 min defrost cycles waste energy.

> Demand
>defrost is preferable.

>>> http://www.youtube.com/watch?v=9gfnmVB5q3c&NR=1
>>> I have a Goodman GSZ (installed Nov) that has started making the same
>>> noise during defrost. There is also a neighbor with a Frigidaire that
>>> makes a similar noise during defrost. He had an HVAC tech come and
>>> tell him that is the way these things work. That was a quick 100
>>> bucks.
>>> I am waiting for a HVAC tech to come but if he also tells me this is
>>> "normal" the world will have one less HVAC tech ;)
>>> I paid $540 for commisioning the unit - 3 hours labour. The $40 was
>>> for a filter/drier. After checking I've found that there was a drier
>>> already installed so this was a waste. BTW, records show 6.6 ounces of
>>> R410 was added for tubing but none for extra filter.
>>> The unit ran fairly quiet for about two months until the temp went
>>> down to 20F. Should there be a crankcase heater?
>>> Frosting rarely completely covers coils - not much icing on bottom
>>> sections. Defrost setting at 30 minutes.
>>> How well do the sound blankets on the compressor work?
>>> Looking forward to the replies - good, bad, funny AND ugly......

>> As there were no replies to this, I'll try to answer it myself.
>> (still awaiting the (new) HVAC tech to come and perform his magic.)
>> In the meantime, I installed a crankcase heater and sound blanket and
>> found that the accumulator was rattling on startup due to missing nut
>> on mounting bolt. This caused the sounds to be exacerbated.
>> I think the problem is scroll compressor slugging on foam created by
>> insufficient refrigerant or migration.
>> Original charge was to be by weight.
>> Factory charge: 35.14 oz
>> Extra line charge: 6 oz
>> Missing charge for unneeded filter: approx 6 oz
>> I checked refrigerant charge using the hot gas method (I'm a retired
>> industrial instrumentation tech so this was no big deal) and found a
>> temperature rise of 119 on the hot gas line.
>> I also ran the unit on a cold, humid day for an extended period and
>> found VERY distinct frost banding on bottoms of coil sections. This
>> unit is at my mother's house so I did not find out about problems till
>> recently so I cannot say when it started. The low refrigerant may also
>> be caused by leak in system. If so, I'll be pretty pissed off if it's
>> in one of the installer's connections!
>> I called the owner of the original heating/HVAC company and he tried
>> to bullshit me. I should have recorded his dumb comments as he tried
>> to explain the above and say it's "normal". He would not allow me to
>> speak directly to the tech. He wants another $500 to remove the filter
>> and adjust refrigerant. From his comments, I figure he is an old
>> heating dude that got into the HVAC business by hiring an HVAC tech
>> and doesn't know much himself.
>> I had two quotes for original installation which entailed brazing
>> connecting refrigerant tubing, adding appropriate amount of
>> refrigerant and checking system operation. Electrical and mechanical
>> installation was already done. Unit was running on aux heat and
>> airflow checked using measured line voltage and current of strip
>> heater in conjunction with temp probes. (756 CFM at medium fan speed
>> for 2 Ton unit)
>> The two quotes were $500 and $350. I took the higher because I wanted
>> a good job done. Go figure....
>> I have expanded heating data charts (ambient from 65 to -10) for
>> installed split-system to make life easier for tech. BTW, all this
>> information (including fact that filter was already installed) was
>> available for original tech but he just thumbed through it and
>> proceeded to do his job. I trusted him. Now I wonder if he
>> contaminated the system during install.
>> Will post results from new HVAC tech when he finishes.

>
> Goodman equipment is a half step above Intertherm mobile home junk. Consumer
> Reports doesn't even rate Goodman because there are so many problems because
> of internet sales and lowest bidder installs. Did the tech even pull a
> vacuum on the system before charging? Did he even own a micron gage, let
> alone how to use it?? or... did he just let the vacuum pump run for 15 or 20
> minutes and call it good?? BTW... 30 min defrost cycles waste energy. Demand
> defrost is preferable.

>
>