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New AC system not cooling

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Discussion starter · #21 ·
Hey everyone, I appreciate all the great info so far.

Today I called Trane and explained what is going on and they said they will support me if the installer doesn't sort out the issue.

After slowing down the fan speed and increasing the amount of refrigerant in the system, here are the new issues I am facing:
1. The system is extremely ineffective at removing humidity
2. The master bedroom feels about 2 degrees warmer than the main floor, the other two bedrooms feel different as well but less significant
3. The system runs about 11 minutes each cycle as previously stated

It's very bizarre to me, the temp will be 76 in the house and 90 outside. While you feel the temperature decrease when you walk inside, it feels humid and sticky - not very "comfortable".

My dad just flew in to town and noticed the humidity level indoors. He also made a weird comment that his glass of water was excessively sweating. It was dripping after a short period of time. A sweating glass is common as the water rises to the room temp but he noticed it appeared to be significantly worse than his last visit.

My neighbor had the exact same system installed in his house last week, his is a 3.5 ton vs my 2.5 ton because his house is larger than mine and he immediately noticed the humidity when walking in the door. He said he keeps his set to 77 and feels "crisp"


My biggest concern is the humidity now, a coworker told me about his nightmare of a HVAC system that was having the same issue which resulted in a severe mold problem.

Any advice on what's going on? The air exiting the vents feels a bit cooler than room temperature but not to the point I would expect. The air began to feel cooler when the tech slowed the speed of the blower motor but that makes me wonder if the coil is getting to a proper temp if it's unable to properly cool the air being passed across it.

For the bedrooms further away from the handler, do you think the high pressures from them cranking up the blower motor to max speed might have caused some leaks in the exchanges?
 
#23 ·
I think the work was incorrect.
 
#24 ·
Petercass88 said:
The guy that was out today looked at the bucket of "water" I asked him what to do with it and he had this "wtf" look then said I can just dump it and they did that to avoid venting it into the atmosphere. Still didn't seem right but sounded like he was doing a CYA. Is it okay to just dump the bucket?

I'll follow up with the office to confirm the warranty. I paid extra to have parts and labor covered for the full 10yrs.
Click to expand...
Putting refrigerant into water does not absorb it. He effectively did dump it into the atmosphere. This guy is a total HACK!
I shudder to think what other stupid things they have done. You'll be grappling with his lousy installation for years.
BTW, equipment comes with refrigerant for a 15 foot line set. He should have added refrigerant for a 25 foot line set, not removed it.
 
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#25 ·
Can you please post pictures of the installation?
 
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Discussion starter · #26 ·
I will post some pictures up ASAP, I'm unable to do so from my cell so I'll post up on my computer tonight. I again appreciate all the support so far, my dad is at the house and said it's comfortable at 76 degrees. My biggest concerns now are - is the compressor damaged from being taxed over the past 3 days with 90+ degree weather with an improper refrigerant charge? Also the copper line set was damaged when being shoved up through the roof and they had to cut out a section and solder in replacement - how will that hold up over time?
 
#27 ·
One of the ways that "more efficient" systems save energy is by doing the cooling job more slowly. However, if you are having a humidity problem, the system SHOULD be running longer. Sometimes, the temperature of the evaporator can limit humidity removal.

I also service a store for a local businessman, and when I stopped by his house, his wife was using 76° as a cooling setpoint. The house felt awful. I measured humidity in the 60% range. I told her that in order to get rid of the humidity, she would have to let the system run longer by lowering the setpoint to 71°.

So, for you, I would lower that setpoint and see if the humidity drops with the temperature in the house.

If Trane says they will back you up, then ask them to recommend a contractor. They know who the guys are that can identify and fix the problems caused or unrecognized by others.
 
#28 ·
The 2.5-Ton unit appears to be oversized as it only runs 11-minute cycles at 90°F outdoors.
From each startup it won't do much dehumidification running only 11-minutes.

On that oversized unit, I'd want a TXV metering device & slow the airflow CFM to 325 or 350-CFM per ton of cooling; 325 * 2.5-Ton is only about 813-CFM.

Heat pumps have a suctionline accumulator to protect the compressor from liquid slugging; many decades ago some Makes of A/Cs had accumulators on them.

They have to make certain that slowing the airflow that much does NOT risk slugging the compressor.

Is the evaporator oversized compared to the condenser? Should be the same capacity sizing for better dehumid work.

Nearly all indoor summer-design uses 75°F @ 50% relative humidity; it should maintain 50% or less RH.

You really can't compare the new 2.5-Ton unit to the old 2.5-Ton 10-SEER as differing wind velocities changes infiltration rates, there are too many variable such as outdoor humidity levels, etc.

Plus the 10-SEER had a bigger capacity compressor which would pull evaporator pressures & Temps lower under heavier loads; better engineering for indoor humidity control; new higher SEER units need to run longer at a lower indoor airflow CFM to achieve the same comfort result.
 
Discussion starter · #29 ·
Ok so 3rd tech visit! They added another 3lbs of refrigerant and seems like this guy knew Trane and admitted that this company doesnt perform Trane brand installs often and said that Trane is a bit more difficult to dial in as opposed to other builder grade brands.

I am sadly away from home to report the current conditions myself but my dad is in town visiting and stated the following:
Temp is set at 76
Humidity feels low
at 91 degrees outside yesterday the unit would cycle on for 6 minutes (plus another 1.5 mins on the blower after the compressor shut off) and stays off for about 15 minutes. Effectively 18 mins of condenser run time and 22.5 mins of handler run time per hour in the heat of the day.

Some home factors:
1400 sqft
All new double pane windows
New blown in insulation in the attic
concrete tile roof

Attached are some photos of the install as well
 

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#30 ·
That is an ass-ugly install. They couldnt be bothered to turn the unit so that the line set wast so long? Inside, wiring is willy-nilly and a lot of vapor line insulation is missing. It will drip condensate everywhere. (Did they add insualtion after they brazed it??) Tape likely is covering bad metal work. And the condenser looks too close to the meter, but it's hard to tell from the pictures. I hope they adequately covered that giant hole in the house.


By the gross numbers, you appear to be WAY oversized.
 
#31 ·
HVAC_Marc said:
That is an ass-ugly install. They couldnt be bothered to turn the unit so that the line set wast so long?
Click to expand...
Mark, in Houston code says we have to have the unit turned like that so the service door is in that position. We got flagged once for this, and I had to go back, turn the unit, and add to the line-set, and install a new whip. I was not happy, because it looked terrible, and our unit was not up on blocks like that, it's just asking for someone mowing to hit the line-set. Go figure! :(



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#32 ·
Mr Bill said:
Mark, in Houston code says we have to have the unit turned like that so the service door is in that position. We got flagged once for this, and I had to go back, turn the unit, and add to the line-set, and install a new whip. I was not happy, because it looked terrible, and our unit was not up on blocks like that, it's just asking for someone mowing to hit the line-set. Go figure! :(



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Click to expand...

Thank you for the correction. Does a position further from the home negate the need for turning the unit? I assume they want "ready access"?
 
Discussion starter · #33 ·
I asked this question of the installers because the trane logo faces the wall... hah... they said its due to code. They would either need to space the unit further from the house or turn it in the orientation its in. The unit is up on 2 pads plus concrete blocks because I am in a high risk flood zone. (even though my neighbors who have been here for 40 years said they have never seen a single home flood)
 
#34 ·
Petercass88 said:
I asked this question of the installers because the trane logo faces the wall... hah... they said its due to code. They would either need to space the unit further from the house or turn it in the orientation its in. The unit is up on 2 pads plus concrete blocks because I am in a high risk flood zone. (even though my neighbors who have been here for 40 years said they have never seen a single home flood)
Click to expand...
Thank you for the confirmation.

There are steel frames made that you can mount to the home so that the condenser can be placed off the ground. IMO they look nicer than a bunch of blocks under the unit. A little late now, but if you have it changed in the future...

Is there a specification/measurement as to what "ready access" is in your area? In my area, it is 12" or whatever the manufacturer specifies, but no less than 12".
 
#36 ·
Petercass88 said:
I believe he said 24" from the home, I would need to do some digging or ask the inspector for confirmation.
Click to expand...
I was just curious for my own edification. It's not necessary to go through that work for me.

that would place it in your walk way. :( so I guess the options are - a narrower walk way or ugly unit positioning.

I sure would have tried to make the line set nicer though. Putting the drier inside would have helped a lot.
 
#37 ·
HVAC_Marc said:
Is there a specification/measurement as to what "ready access" is in your area? In my area, it is 12" or whatever the manufacturer specifies, but no less than 12".
Click to expand...
When we did that job were we had to come back and turn that unit, we actually set two condensers. One was and existing replacement, and one was for a new master bedroom add on.
The line set come out on the corner of the home on the existing unit, so when we replaced it, it was not obstructed, we set the new one for the add on next to it, so it was obstructed the existing unit we replaced.
The inspector tried to make us move the two units farther apart, to 24" but I showed him were Ruud said in their install manual, 12" is all that's required, so he let that slide. I'm not positive, but I think they want a 32" clearance from any thing on the service door side, heck when we measured we only had 36" to the wood fence. Good thing we had 36" or I guess we would have had to move the entire unit to a different location.
I've actually done jobs in neighborhoods that their deed restrictions won't allow you to set a unit any closer than 36" from the fence.


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#38 ·
We have similar rules here, mostly for HOAs. Condensers cannot be closer than 5 feet to the property line. In many cases this means that they have to be moved to the roof because the deck on the rear of the home puts the condenser too close. Then there's the issue of the neighbor's visuals being obstructed by a condenser, bla bla bla, lawsuits, etc... and the unit gets placed right back where it was originally.
 
#39 ·
Mr Bill said:
Mark, in Houston code says we have to have the unit turned like that so the service door is in that position. We got flagged once for this, and I had to go back, turn the unit, and add to the line-set, and install a new whip. I was not happy, because it looked terrible, and our unit was not up on blocks like that, it's just asking for someone mowing to hit the line-set. Go figure! :(



Sent from my iPhone using Tapatalk
Click to expand...

However, it does satisfy the NEC problem: when a unit faces the building, 3 feet of space is required between the energized components in the service section and the building itself, which is considered to be a grounded wall.

When the unit is turned so that the service access is not facing the building, the problem goes away. That is most likely why the inspectors are having the units turned that way.
 
Discussion starter · #40 ·
Hi everyone - next round of info from this install...

The owner of the company finally called me after he requested we only communicate through email and I left him quite the long email saying there are two pathways we can go down to get this resolved.

He is going to come out and install a new lineset so I no longer have a botched together one and is going to go over all the work completed and make sure its to his satisfaction as the owner of the company. I also requested that when the new lineset is installed correctly, that the technician who seemed to know what he is doing to get the system properly cooling be the one that comes out to re-add refrigerant and make sure the system is properly charged and running efficiently.


One concern I raised is that the compressor was struggling on a low refrigerant charge from Wednesday to Saturday (finally fixed on saturday) in 90+ degree temps. I said this cant be healthy for the compressor and might have a latent failure. He said that shouldn't be an issue and if the charge was too low there is a failsafe built in that would shut the compressor off if refrigerant levels were too low causing pressures to be too low. Is this true?
 
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