Thoughts on the Goodman GSX13 Air Conditioner

[washman]

This unit is matched to the 96% AFUE furnace.

The unit is rated at 13 SEER, the bottom level for their efficiency. These units are not sellable in the SW or SE part of the US.

The installer placed it on a composite pad on the back side of the house and ran the lineset through the wall up over the ceiling, then down to the air handler. There is no TXV on this setup, just a .057 orifice controlling the flow of R410A to the evap coil.

Both the condenser and evap coils are copper with aluminum fins.

The unit is 1.5 ton with a single stage Copeland Scroll compressor and a single speed made in China PSC fan motor.

I do notice that R410a does not pull down as quickly as R22 did at the old condo. Nor does the suction line "sweat" in dank weather. However the air coming from the vents certainly is cool. The installing contractor came 3 weeks ago to charge up the unit as they could not do a full charge in the dead of winter when it was physically installed. I'm not sure what the total charge is but he used some different gagets to measure 'superheat" and supercool rather than the old school set of mechanical gauges that I am accustomed to.

The warranty is full 5 years, 10 on the compressor. It is pretty quiet outside, I'd guess the fan speed to be about 1000 or so RPM. I would expect pretty good longevity as this unit in W PA will run say 3-4 months per year and with the house being as well insulated, I might not be running it say as much as I did in the condo.

 

[gusherb]

Anything higher then 13 SEER isn't really necessary for cooler climates like ours. The 13 SEER units are already very cheap to run compared to older 10 SEER and below condensers.

R410 and R22 should have NO difference in "pull down" (I assume you're talking about supply temp and not how fast it's cooling the house down right?) And if there's any bit of that suction line exposed to the humid air it SHOULD be sweating or that to me is a red flag that something's not working right.

Did your condo system have a TXV? Those usually start cooling much quicker then orifice based systems since they hold the pressure in the high side while off so it doesn't have to build up pressure each time it cycles back on.

Have you checked your supply air temp yet?

 

[washman]

Negative

Condo had an R22 Sears/Whirlpool unit with inefficient furnace and no TXV, just a cap line. Run from outdoor unit there to evap coil was about 13 ft.

At the new location, I would guess about a 27 ft total run from outdoor unit to evap coil.

Pull down, I was referring to how quickly, based on "hand feel" the temp of the discharge air was from the ceiling mounted outlets. Given that, I neglected to realize that the ducts are indeed up in the attic and it is hot up there with the sun shining. Thus the hotter air needs to be displaced, pulled into the air handler and pushed out for a bit before I notice a good cooldown.

Have not checked on supply air temp as of yet. Like I said, a while back the HVAC contractor came out and completed the system charge to correct capacity.

Once it is percolating, so to speak, the air is quite cool indeed and the t-stat is satisfied with a 10-20 minute cycle time with about 45 min to 60 min off time. Temp stays about 2 degrees either side of t-stat setting.

 

[2packs4sure]

It's either undercharged or it has too much airflow.

I think that .57 orifice is TOO BIG for 1.5 tons and causing it to run a high suction pressure.
It's either that or it's undercharged and/or it has too much airflow.
If the air isn't coming out of the vents like a jet then i'd bet on that orifice.
It's also possible they installed it on a cold day and just never got the charge right.
BUT.
That orifice......... I don't like it, i'm thinking high 40's and .50 max for the orifice for 1.5 tons 410a.

Call Goodman first if you can and confirm that orifice size.

If it gets to the point you have to call someone else out, INSIST they check the charge using the superheat method.
And make sure they have some smaller orifices on the truck.

If they push back AT ALL on that call someone else.

They should be able to swap that orifice and adjust the charge in the $300 range unless it's just hard to access and work on.

They might actually have to REMOVE freon with the proper orifice.

 

[washman]

pic of unit

 

[2packs4sure]

The 1.5 ton 410a Goodman condenser is shipped with a .51 orifice.
That WILL make a difference.

If the set up has a 13 ft lineset and an oversized orifice that will result in high suction pressures with the factory charge of refrigerant.
Even if he removed some freon to compensate for that short lineset the .57 orifice still puts the system on the edge at best.

Are you SURE it has a 57 orifice and is it a Goodman coil?
What was the temperature outside on the day they installed it?

I've been out of the A/C game since 2010 after 21 years but i think i'm in the ballpark.
Modern systems are VERY sensitive and you can't fudge em' with refrigerant charge variations like back in the day.

 

[washman]

Wil check the orifice tonight for sure

13ft line set>>>>OLD place

approx 27 ft>>>>>NEW place.

 

[2packs4sure]

27 ft that's fine.
Yea, check that orifice you may have mistaken a one for a seven though you'll never know for sure until you're holding the orifice in your hand.
Hopefully the installer installed the 51 that came with the condenser in the coil at the time.
Maybe you could ask him.

If the orifice can't be CONFIRMED then the first step is to have someone put their gauges on it and see what's happening.
If the superheat is off, it's not overcharged, the airflow is normal, and she's running high a suction pressure then the orifice is probably the issue.

Hopefully it's just slightly undercharged for some reason. That will be the most painless scenario.

 

[washman]

I doubt it is undercharged

because the HVAC guy came out late April when it was about 80 degrees and added 410A to the system. It was installed over the winter, physically speaking, but they did not add additional 410A until late April like I said.

the HVAC guy DId have his gauge set, digital, and mentioned something about supeheat being ok.

 

[gusherb]

Of course, I forgot your ductwork was in the attic. Our second story system is too and it takes about 10 minutes if it hasn't run in a long time on a warm day for it to blow cool. The suction line is of course warm until it has been running awhile in that case.

The other thing that 2packs4sure reminded me of is much of the time contractors don't set the cooling blower speed correctly and leave it on the high setting which unless it's a 3.5-5 ton system (depending on how big the furnace/blower is) is WAY too much airflow for the size system it is, usually causing reduced dehumidification and sometimes excess noise if the ductwork can't handle the airflow.
I've had to change more blowers to the low or medium speed than I can count because it was just left at default causing what I just stated above.

 

[washman]

One thing I noticed

is the air coming out of the condenser is warm. That would suggest good heat transfer and good airflow on the outside unit.

Like I said, this whole setup is single stage, no 2 stage or modulation of anything.

I noticed a tad bit of condensation on the suction line coming from the evap coil in the utility room.
Keep in mind this is a bit of a lengthy run from there to the outside unit.

Airflow from all registers is quite strong. I'm not certain of the inside fan RPM, I know it can be adjusted on the control board on the furnace but I'm not about to muck with it. Everything seems to work just fine right now and I'm loathe to upset the apple cart.

Every room has 2 return air vents, one up top and one close to the floor. The upper most intake can be closed off to where only air entering from bottom is allowed. The main air return grills are in the living room. Both of those are fixed open. No shutoff here. The HVAC contractor certainly has a thing about return air! Most houses, especially Ryan homes, have at most ONE return inlet.

One thing for sure is the Aprilaire filter is mucho buckage! Not a 99 cent piece of junk from walmart, this thing stops pretty much any dirt, pet dander, you name it from entering the ductwork. I found one on Amazon for something like 32 bucks plus shipping for the genuine article. I think it is MERV 13 or something like that. Never had one before, I always was used to those 1/2 inch things you get in a 3 pack at a local BIG BOX. Flanders was the brand I always used. This thing is a whole new beast for sure.

 

[gusherb]

The good thing is any contractor that pays attention to proper return airflow is probably paying attention to other important things as well. Proper return air ductwork is THE MOST neglected thing when it comes to HVAC installation and design right next to proper equipment sizing and supply sizing.

I have the same Aprilaire filter as you, it originally came with the Merv 11 filter but I got the Merv 13 for the same price on Amazon for about 40 bucks. The good news is they only need changing once a year, maybe longer if your home isn't dusty like ours. I like them because they don't lose much airflow as they get dirty. The 1" Merv 7 Flanders filters are one of the worst for restricting airflow, I stopped using those and went to the Merv 7 True Blue filters when I figured out they were choking out a few furnaces I maintain.

 

[washman]

My research on all HVAC brands

is a lot of good and bad.

The common denomiator I see is lazy, half ass installation, incomplete setup especially on the newer 2 stage units, poor placement of thermostat, incorrect settings on thermostat.

I've seen rave reviews on Trane and also an equal number of flame posts about Trane.

I know this much, NONE of them, save Carier, Trane, make their own compressors. No one makes their on ignitors, gas valves, or control boards. All that stuff is off the shelf. Heat exchangers and cabinets and grills are about all that is made in house regardless of brand.

Thus the only real world variable is installation. And it is shocking how much is done so poorly out there.

 

[gusherb]

And it is shocking how much is done so poorly out there.

The irony to that is the states where HVAC is VERY important such as Arizona, TX, and every southern state all have by far the worst reputation for installation quality.

It's funny to me because they need good cooling which comes by good design and install and that is VERY rare to find there so most people suffer in discomfort and/or very high electric bills due to oversized equipment paired to undersized ductwork and not sealed at all. And those systems barely perform in the heat they get.

Up here in the Chicago area the worst HVAC systems look great compared to some of the better stuff down there. and with the way most HVAC systems and equipment are sized here, when we had the heat wave in 2012 most homes had NO problem at all keeping it at whatever temp was desired when it was up to 105 outside. (even though according to Manual J, cooling equipment in the Chicago area only needs to be sized to maintain setpoint up to 92 degrees ambient).

Basically saying our HVAC systems work better in "southern weather" then systems down there do in their own design conditions.

 

[epixstar128]

Goodman is the Kia of the hvac world. Nothing wrong with it just more builder grade.subcooling and super heat are as lways the ways to charge a system txv or not. Nothing wrong with a fix orifice.
Check your incoming vs outgoing air. Should be around 20 degrees.don't worry about orifice size let the installer do his job. They made the right move coming back with a load in your house to finish
The charge.
Ten years in the business
Working on hvac and refrigeration

 

[washman]

Goofed

Unit is GSX130241DB in other words 2 ton, not 1.5 like I thought.

Orifice tag on evap coil shows 057 not sure what is on the condenser unit.

 

[2packs4sure]

GSX130241D Shipped with Orifice 0.057

That's the right one for the two ton.

 

[2packs4sure]

What's the model # on the evap. coil ?

 

[washman]

evap coil is

ACPF1824B6DB