Brand new A/C system- same old problem

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  #1  
Old 07-05-16, 01:01 PM
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Brand new A/C system- same old problem

In 2012 daughter moved into 2nd floor in 9-year old 4-story condo in Atlanta. Outside unit is located on the roof. A/C was working very well for 3 years. In 2015 inside unit started freezing up.

Called A/C tech who stated there was no leak. He put in more Freon but unit froze up again next day. This happened a couple of times. Tired of paying money for nothing we decided to buy a brand new 2-ton system with 410 coolant (Goodman 14 Seer compressor and air handler) from a different AC guy, which was referred to my daughter by a friend).

He installed both units on June 21st and it froze up twice, worked a few hours and now does not cool at all. After 4 different visits and different explanations ("assistant forgot to take off cover on air handler"..."extra long lines from roof to 2nd floor might cause the trouble" on last visit he stated "He sat on the roof and watched pressure for 1 hour and it was perfect and we were good to go". AC never cooled and daughter turned it off.

When we wanted to verify installer's certification number, he got belligerent and will not return calls even though we paid him full amount and have 5 years warranty on labor. Now convinced he is neither licensed nor a legitimate business and probably has lack of experience.

But the question lingers...could it be the same old problem on a brand new unit? FYI...He did not replace lines but flushed the old lines of R22 and added new coolant.

Desperate in Hotlanta,
Marina
 
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  #2  
Old 07-05-16, 02:41 PM
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Did he replace the evaporator coil as part of the new system installation?
 
  #3  
Old 07-05-16, 09:11 PM
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It appears both units were replaced.

Since both units are doing (or were) doing the same thing..... the problem still exists that was there from the start. It sounds like there is not enough air flowing thru the unit. Could there be a central return grill with a clogged filter behind it ?
 
  #4  
Old 07-06-16, 04:58 AM
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Yes, both inside and outside unit were replaced. I assume the evaporator coil is part of the brand new air handler unit inside??

I know this is probably a stupid question but where would the central return grill be located? Inside the condo?
 
  #5  
Old 07-06-16, 05:38 AM
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The evaporator coil resides in the air handler, however it must be matched to the outside unit (compressor/condenser). Usually, when an A/C unit is replaced, a new evaporator is installed as part of the install. If there is a leak in the system, it's often the evaporator that's bad. That's why I asked if you knew if it had been replaced. However, Pete's idea of insufficient airflow is a good one.
 
  #6  
Old 07-06-16, 08:38 AM
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Central return filter is located right before the blower or evaporator in the air handler Or inside of your central return vent somewhere in your room. If the filters are all clean, than you need to check the blower to see if it is too slow. Anyway, do you still get strong airflow like before ?
 
  #7  
Old 07-07-16, 06:51 AM
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No, I cannot even feel any airflow. Had a guy out yesterday to do a diagnostics test. He said units seem to be installed properly but Puron coolant is showing undercharge and overcharge at the same time. He is not sure what causes this and will talk to Goodman for advise. Any ideas out there by the HVAC detectives? What could cause this problem?
 
  #8  
Old 07-07-16, 06:55 AM
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Will double check to see if evaporator coil was part of the new air handler or not and if it matches with outside unit. Thanks for the tip!
 
  #9  
Old 07-07-16, 08:13 AM
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It's not possible to see undercharge and overcharge at the same time. Sounds fishy to me.
 
  #10  
Old 07-07-16, 08:37 AM
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This was a licensed new guy we hired to do a diagnostics test. He actually took his time and was really thorough. He checked equipment (outside and inside) and couldn't find any obvious faulty install issues. But the problem was with the coolant. He stated the following: "Superheat, which is used to calculate charge, was overcharged at 2 (8-10 normal) and the suction pressure was 110 and should be higher". He said something like system/coolant is basically overcharging and undercharging at the same time. Does it get any weirder than that??
 
  #11  
Old 07-07-16, 10:07 AM
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Over charge and under charge same time ? Does not make much sense. You said no airflow at all ? Can you set to 'Fan only' mode and see if you feel any air flow ?
 
  #12  
Old 07-07-16, 10:10 AM
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No doesn't get weirder than that...HA. He's statement doesn't make any sense. Most of the time subcooling is used for charging. Are you sure he didn't say Subcooling?
 
  #13  
Old 07-07-16, 10:52 AM
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Just so that you are aware.... we don't discuss charging pressures and issues on this board.

I asked about airflow. You said there was very little. Very little airflow will cause system pressure problems.

You need to address the low air flow issue.
 
  #14  
Old 07-07-16, 11:29 AM
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Pete, just out of curiosity...why are charging pressures not discussed?

Regarding air flow...air handler filter is brand-new. No vents are blocked or closed.

Could the bad pressure have something to do with the coolant lines? I have had 3 different AC guys tell me there is no leak. Would reflushing lines and refilling with Puron be helpful or a waste of time?

Please!!! Somebody out there must have experienced something similar. I will reward anybody with a cool hat who helps me solve this mystery, which will result into cool air for my daughter and her constant whining about the heat to stop.

Frustrated to the max in Hotlanta,
Marina
 
  #15  
Old 07-07-16, 11:45 AM
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Clocert: Daughter states when AC was set to 'fan only' she felt no air flow either. Right now system is actually cooling with temperature showing 73. Will be interesting to see when it will freeze up again.
Tech yesterday adjusted Freon psi to manufacturer spec and recommends replacing 14 inch with 16 inch duct. Also recommends TXV to help regulate freon better... Don't know what that is but will find out. Could those recommendations fix pressure problem?
 
  #16  
Old 07-07-16, 11:49 AM
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Skaggsje: Not sure about anything cuz I was not there. But daughter wrote everything down that he said so she could fill me in later on. She states he did not say anything about 'subcooling'. But tech also said that reading both, over- and -under charge was a weird problem that he had never encountered before.
 
  #17  
Old 07-07-16, 01:11 PM
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I don't how to explain this any more clearly.... the air flow thru the coil is what keeps it from freezing. The airflow thru the coil also directly affects the system pressures.

If you aren't feeling a GOOD airflow from the registers then there is a duct work issue or the blower is running too slow.

Since an EPA issued license must be held by anyone working with refrigerants and there is no way to determine who has a license and who will use the information they read.... the management of DIY has instructed us that no charging instructions or system pressures are to be discussed. http://www.doityourself.com/forum/ai...ng-your-c.html
 
  #18  
Old 07-07-16, 01:22 PM
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Something is not right here. If you don't have air flow (means you don't have air blow into the room), you won't be able to cool your room down to 73 degree. If your room is cooled down to 73 degree, you must have air flow. So ask your daughter again. I am guessing you do have some air flow, may be not strong enough (just a guess).
 
  #19  
Old 07-07-16, 01:38 PM
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Pete: I will not discuss any more subcooling or superheat numbers. Just googled those terms and there are very helpful articles on the net for techs to troubleshoot this complex issue. Believe me, I have no intentions to charge my own AC system. That's what the experts are there for. But it looks like some techs have problems getting the pressure right with the new Puron 410-a coolant. Heard it was easier to charge the old R22 Freon.

Since you seem convinced that the problem with my brand new system is not improper charging of the coolant but airflow, could this relate to duct work anywhere in the walls of the 4-story condo building? If yes, where do I even start with that??
 
  #20  
Old 07-07-16, 01:56 PM
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Clocert: I was also surprised to hear that it went down to 73! I am going over there tonight while the system is still running to actually check every vent for airflow.
Thanks for all the tips everybody!
 
  #21  
Old 07-08-16, 04:47 AM
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Well, so far so good. System has been working since the AC tech two days ago adjusted Freon. He states on his invoice that unit appeared to be overcharged and still seems to have some issues. Would the TXV he recommends solve the pressure problems long-term?

Went to the condo and checked all vents for airflow. Since the ceilings are very high I had to stand on a bar stool and yes, I did feel cool air coming out. Subtle but yes! So at this point just waiting to see how long it will last before it freezes up again.
 
  #22  
Old 07-08-16, 07:34 AM
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So no mention of static pressure checks or airflow? This would tell how well the ductwork is set up.

A TXV is a normally a good thing (other than an additional point of failure) as it can make a system more efficient by regulating the evaporator coil temperature. It might help a bit for you but it doesn't solve any underlying issue.
 
  #23  
Old 07-08-16, 11:51 AM
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If the cool air is cold enough and it can cool the room down or below 73F, and it can run for more than 3 days, then there is no need to worry about TXV. you need to find out how cold the cool air is. Take a thermometer , put in front of the register (about 1 inch out) and find out what is the cold air temperature and see how many degrees it is lower than your room temperature at that time. If you have at least 15F lower, you should be OK.
 
  #24  
Old 07-08-16, 12:54 PM
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Astuff: Should I mention to the tech to do a static pressure check?

Tech did state that the 'duct on top of airhandler was not installed properly'.

I guess the duct work in the rest of condo is okay since I felt airflow coming out of most vents.

Thanks for the TXV info!
 
  #25  
Old 07-08-16, 12:58 PM
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Clocert: System still running as of now. Daughter turned it up to 74. Will tell her to do the thermometer test. Thanks a lot for that tip!!
 
  #26  
Old 07-08-16, 05:22 PM
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All the ductwork & Return-Air Filter area issues need to be effectively dealt with first...
A refrigerant system restriction can cause the indoor coil to freeze-up.

Simple easy anyone can do ways to check the performance of your central air conditioner so, you can call an Energy Efficiency HVAC Technician to get the various problems revealed & fixed.

You can run a ballpark analysis of how your system is performing in respect to its 'Nominal Rated Btuh' you need at least the following numbers:
Performance Data Collection – Best Time to collect data is Late afternoon around 4:30 pm, when attic is HOT; also when outdoor temps are around 80; 85; 95; or higher.

1) Helpful; Tonnage & SEER or year Mfg'ered or bought, the outdoor condenser Make & model number: ___________

2) TXV or, orifice metering device? __________. Only if U know…

3) Outdoor condenser’s discharge-air-temperature ______-F

Subtract Outdoor air temperature:_______ = _______ Condenser Air-Temp-Split ________
4) Need the ‘Indoor’ percent of relative humidity - away from Supply-Air outlets _________
Walmart has very low-cost ACU-RITE digital humidity & Temp monitor - every A/C User should have one
5) Indoor Return-Air Temperature ______

Subtract Indoor Supply-Air Temperature ______ -F

Indoor temperature-split _______-F

Click; Reply With Quote: Reply with quote - with filled-in data.

We Need the above information for troubleshooting & ballpark performance analysis.

A TECH should check the blower wheel blades & evap-coil for possible lint build-up; then, perform static pressure reading & compare to the blower chart or graph to check for proper airflow CFM through the evaporator coil. If a new system they will be clean.

Adequate indoor airflow to & from all rooms is extremely important to heat removal performance & other temp-data readings; the indoor coil needs to be adequately heat-loaded for optimal performance.
 
  #27  
Old 07-08-16, 07:37 PM
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4 story condo

Sounds like you have a ductwork problem. probably impossible to fix without tearing out drywall and running new properly sized ductwork. Real estate is way up right now best thing to do if you bought it cheap is to sell it and buy a better constructed unit with the windfall
 
  #28  
Old 07-11-16, 06:07 AM
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HVAC retired: Thank you, Sir, for the detailed info! Unit is brand-new. Starting to think the guy who installed system less than 2 weeks ago, did not properly fill up coolant and overcharged system. Had another guy here who adjusted coolant and system has been running for 6 days now. But he did state that there still seems to be an issue with the pressures and he will have to research why it basically shows over- and undercharge at same time. Waiting to hear from him. Hoping system will not freeze up again.
 
  #29  
Old 07-11-16, 06:10 AM
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Former member: I will definitely not sell condo just because AC problems. My daughter would just have to make do with huge fans in every room during the summer...lol.
 

Last edited by mars_marina; 07-11-16 at 07:44 AM.
  #30  
Old 11-01-16, 01:34 PM
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Hello! I hope everybody had a great summer. Quick summary of ongoing problem. Bought a 5-year old condo in 2012. A/C worked fine for about 2 years and then kept freezing up inside. Tech could not find a leak in the system and kept adding R-22 Freon. He did mention it might be trash in the lines but said there is no way to test it.

Fed up with these freezing up problems, I purchased a brand new A/C unit w/R-410 in June 2016, which kept freezing up from the start! Installing contractor was not able to fix issue and stopped returning my calls. Hired another tech who said system had coolant pressure issues that he had never encountered before (details in previous posts within this thread) but was able to make A/C work. System has been cooling properly since early July! A couple weeks ago when it got cooler, my daughter turned A/C off. Yesterday she turned it back on because of this extreme warm weather we are having here in Atlanta, and over night it froze up.

Remember, the freezing up issues in the 9-yr old unit were the reason why we purchased a new system in the first place! She immediately contacted the same A/C tech who was able to make the system work and asked him if this was something that should be addressed now or should she wait until spring. He recommends that it should be fixed now because any unresolved coolant issues could reverse in the winter and freeze up the heat pump on the roof of building (which is hard to access) and cause major damage to the coil and, eventually, whole system.

I have to mention that the lines from the roof of the 4-story building to the 1st floor condo A/C are still the same old lines. Installer supposedly flushed the old freon out and filled with Puron.

1. If this flushing is not done properly, can the lines get contaminated and kill the whole system eventually? Is there a way to rectify it?
3. Could the mix of the old R-22 freon and the new R-410A Puron be responsible for the strange Overcharge/undercharge pressure problems the new AC guy cannot figure out.
2. Wouldn't the flushing out of Freon during install of new unit have also flushed out any trash in the lines if there was any?

Thanks in advance for any insight and advise!

Frustrated, broke and fed up in ATL,
Marina
 
  #31  
Old 04-25-17, 01:41 PM
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Hello again!

Can somebody please respond to my last post from Nov 1st 2016? Same issues - same questions are still valid. Just had another diagnostics test done today and they recommend as follows:

Found system freezing up at distribution tubing and suction line past service valve. Piston size is correct. System has restriction not allowing refrigerant to meter properly.
Recommend recovering refrigerant, flushing system with r-11 and nitrogen, install liquid line drier, vacuum and recharge unit per manufacturer specification. $950.

Tech said this should fix the problem....Experts, does this sound like it will fix the problem with this new AC system? And, will flushing the lines also remove trash in the lines, if there is any.


Thanks in advance for an answer.
Marina
 
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Old 04-25-17, 09:08 PM
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First ask tech to check with his boss if you get a refund if his fix doesn't work.

How does the tech know that the piston size is correct unless he took it out and measured it?

Still haven't heard if air flow is OK or not.

Ugly but a short term work-around is to install a freeze sensor that shuts down the compressor https://smile.amazon.com/FSK01A-Good.../dp/B00EO70QHC or similar.
 
  #33  
Old 04-25-17, 09:30 PM
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I really doubt this is a refrigerant problem..... since the old system had the same issue.

I'm leaning towards an air blockage..... possibly something in the ducts moving.... cardboard.... insulation.... maybe a damper.

You should have GOOD airflow from the registers.

On edit:
I didn't realize this thread was this long and that I had previously mentioned airflow.
I stand by original diagnosis.
 
  #34  
Old 04-26-17, 07:46 AM
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Astuff,

Thanks for replying.

Re: Piston size: Tech wrote: Checked piston size (57) which is correct.
Re: Airflow: The condo cooled properly from July 2016 until November 2016 when it froze up again.
Could that still be an airflow problem if it runs perfectly fine for 4 months?
 
  #35  
Old 04-26-17, 08:02 AM
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PJmax,
Thanks for replying! Since I had freeze-up problems with old system and new system that would make sense, but, again, condo cooled fine for 4 months last year until it froze up again.
If there is an air blockage in the ducts, could it intermittently happen like this?
 
  #36  
Old 04-26-17, 08:32 AM
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As I mentioned before, installer, who installed new system in June 2016 might not have flushed lines properly to get rid of the old R-22 Freon before filling with the R-410 Puron. These are extremely long lines reaching from roof of 4-story building down to 2nd floor condo. I have to ask the following questions again because I still have no answers:

1. If the installer of the brand-new AC last year did not flush out system/lines properly before filling it with new R-410 Puran, could this have contaminated lines and could it kill the whole system eventually? If yes, is there a way to rectify it?

3. Could remnants of the old R-22 freon mixed with the new R-410A Puron be responsible for the unusual Overcharge/undercharge pressure problems the 2nd tech from last summer said he had never encountered before?

2. If I let the new AC company flush the system as the tech described (above) would it also flush out any trash in the lines if there is any?

3) Does this flushing out usually work or should I get new lines?

Thanks in advance for any insight and advise!
 
  #37  
Old 04-26-17, 09:23 AM
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Astuff, I googled the link you provided. Available on Amazon for $37. But what exactly does this do?
 
  #38  
Old 04-26-17, 09:46 AM
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There would be no R22 just laying in the lines. There could be deposits of mineral oil left but that shouldn't hurt anything mixed in with POE.
Freeze ups do not indicate compressor problems. That would indicate the compressors working good.
What's the current CFM the air handler is moving? Like actual exact numbers. Should be pretty easy with a pressure drop chart for the evaporator and a manometer to measure static.
Should be between 350-400 CFM per ton of capacity.
 
  #39  
Old 04-26-17, 10:03 AM
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Thanks Roughneck77! I don't know what all that means but will ask tech to do what you suggested.

Let me ask a stupid question to everybody...is it just a myth that freon contamination (if it was not flushed properly and installed properly) can occur and kill AC system or has anybody here experienced something like it before?
 
  #40  
Old 04-26-17, 10:32 AM
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Contaminates within the system can easily kill the equipment. That said, there is no way for the previous R22 to lay in the lines and contaminate the new charge of R410A. It just doesn't work like that.
There used to be much concern over the mixing of the oils but this has proven unwarranted.
The tech should be checking pressures, superheat, subcooling, and exact airflow. All those readings will show exactly what the problem is.
 
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