High Superheat, Normal Subcooling

[pmc181]

I'm working on my own split a/c system and can't get the charge right so the unit will cool. It is a Goodman 4 Ton system with a fixed orifice. The inside and outside coils are both clean and I have good air flow. Since I had high superheat, I added R22 and the suction and head pressure go up, but I'm not even close on the charts. I'm already at 350 head, so I didn't want to add any more freon. Looking at the numbers below, would this mean that the compressor and condensor are fine, but the evaporator is starving for refrigerant due to a clogged orifice? The unit is 8 years old.

Indoor temp= 81, RH=68
Outdoor temp=93
Suction press=65 (should be 38F), Actual suction temp=81F same as room.
Superheat=81-38=43 High

Discharge press=350, (should be 143F) Actual temp=130F
Subcool=143-130=13 Normal

Compressor amps rated at 22, pulling only 18

Thanks,
Paul

[ckone180]

The superheat isn't based on the indoor temperature, it is based on the pressure/temp of the evaporator, which is 38. That is low superheat. Stop charging the unit if you want to keep it. The fixed orifice doesn't control superheat, so whoever taught you how to do this stuff needs to be fired, and fast!
The rating on the compressor is for reference and usually runs much lower than stated. The head pressure is high, and should only be around 275. You are going to destroy your unit.

[Maximus3]

Simply put theres too much refer

[DE J-man04]

If you want to keep that unit working turn it off and call a PRO. You will thanks us later

[pmc181]

ckone180,
I think you missinterpreted what I wrote.
Superheat can be measure at the condensor if you also take into consideration the pressure drop from the evaporator to the condensor. I was saying that the actual temperature of the suction line at the condersor is 81 degrees which happens to be the same as the indoor temperature. The pressure of the suction line at the condensor is 65psig which on a R22 chart is 38 degrees.

superheat=suction line temperature. -saturated suction temperature.

I agee that the head pressure is high and that is why I did not add any more freon.

Also for your information a manufacture rating of compressor amps is one way for an a/c tech to see how hard a compressor is working. It will normally be lower, but if you come accross one that is higher, you should not overlook it as just something the manufacture puts on a label. It's there for you to check and use it as a tool.

Thanks,
Paul

[pmc181]

By the way, I probably should have mention it in my first post. I am an ex a/c contractor with a state license. I didn't work for somebody else, I took the exam and own the license. I am also a licensed master electrican in all 50 states.I gave up my business and just take care of the 3 a/c systems in my home.

Thanks,
Paul

[Carnak]

never mind

[Maximus3]

I gave up my business and just take care of the 3 a/c systems in my home.

How much are you making doing that?
All funnies aside, that is a high load and you mentioned possible restriction. Can you easily look at the evaporator? If so check the distributor tubes going in to the evap. checking for even flow of refer. across evap. thus indicating if you have a restriction.

[ckone180]

I appreciate the explanation on the superheat, I really thought you were refering to the indoor temperature. High superheat is right when you have a heavy load, but that doesn't reflect the normal subcooling at such a high head pressure. Filter-Drier, if you have one, may be clogged. Condensor may be dirty. Congrats on your license, I don't know what state you are in, but some states have a silly test. This type of issue appears to me as someone with a little experience could have fixed. Air flow, filters, cleanliness all affect the system, and could be giving you your problem. Think simple. Also, the ratings are the maximum it should operate at, take for example an AEA4440YXA, labeled at around 9amps, but different applications could result in 5-6 amp readings. That is a 40% difference.

[smokin68]

By the way, I probably should have mention it in my first post. I am an ex a/c contractor with a state license. I didn't work for somebody else, I took the exam and own the license. I am also a licensed master electrican in all 50 states.I gave up my business and just take care of the 3 a/c systems in my home.

Thanks,
Paul

Total BS. If you ever had any type of a/c license and don't know what your problem is here, you dis-serviced anyone's system you put a wrench to. Very basic problem...like an electrician that can't figure out a breaker is tripped. If you were licensed, your state's licensing procedure stinks. JMO.

[orlandotech]

yeah I think he needs to check the piston for the right size. low suction, high SH, high head, high to normal SC spells underfeeding metering device to me. the coil is starved like a mofo ( and overcharged to boot ).

Better call a pro before you nuke the windings in the pump PMC. sorry man but you have the distinct stench of a DIY. If you were a A/C contractor at one time you should be able to determine the problem with your manifold and a pipe clamp probe and a little bit of gut talking to ya, without having to post it here. Why don't you email the guys at the website you bought it from. maybe they can help ya.

[Mr Bill]

Simply put theres too much refer.

Can you have to much refer?

[orlandotech]

Can you have to much refer?

NOw were talkin'

[aircooled53]

I would recover the refer and remove liquid line drier inside unit.I would also check while the system was open , I would check the indoor piston , to insure there is a match to condenser and also check screen to make sure it's not clogged with dirt and other particles..
After vacuum to 500microns and recharge..

[pmc181]

ckone18, aircooled53,Maximus3,

Thank you for the imput. You guys are obviously educated in the A/C field. and know what you are talking about. I will check into the restriction problem.

Carnack, smokin68,Orlandotech,Mrbillpro

First off guys, lets stay professional. I have fired more a/c techs because they ran the same tubing size to every a/c install no matter if it was 25 feet or 75 than you can count. I have fired more electricians for always running the same size circuit to evey a/c unit or cooktop just because they always did that than you can count. This forum like all other should be about helping one another and not bashing. I have spent my whole life in the electrical, instrumentation and a/c trade and yet I am the first to admit that I don't know everything and I am not afraid to ask a question to do it right.

I dont' know how you ended up with a title of professional member or membership committee, but it does not impress me at all. If you want to contribute to this forum that is great, but keep your manners in place.

Thanks,
Paul

[Mr Bill]

Carnack, smokin68,Orlandotech,Mrbillpro
I dont' know how you ended up with a title of professional member or membership committee, but it does not impress me at all. If you want to contribute to this forum that is great, but keep your manners in place.
Thanks,
Paul

Carnack, smokin68,Orlandotech, you guys remember me always talking about
the stoned face owners at the supply house does this guy ring a bell?
Matter fact he is not far from me maybe he is one I have seen.
Matter fact I do remember him now.

[tbox8098]

if you have the credentials you say you have then you should apply for the pro forums and then postt this question in there. Maybe you fired some people that you shouldn't have do to the fact you didn't know what you were doing. I know plenty of guys that have all of the paper certificates and licenses in the world but I would not trust them to hook anything up.

TJ

[orlandotech]

ckone18, aircooled53,Maximus3,

Thank you for the imput. You guys are obviously educated in the A/C field. and know what you are talking about. I will check into the restriction problem.

Carnack, smokin68,Orlandotech,Mrbillpro

First off guys, lets stay professional. I have fired more a/c techs because they ran the same tubing size to every a/c install no matter if it was 25 feet or 75 than you can count. I have fired more electricians for always running the same size circuit to evey a/c unit or cooktop just because they always did that than you can count. This forum like all other should be about helping one another and not bashing. I have spent my whole life in the electrical, instrumentation and a/c trade and yet I am the first to admit that I don't know everything and I am not afraid to ask a question to do it right.

I dont' know how you ended up with a title of professional member or membership committee, but it does not impress me at all. If you want to contribute to this forum that is great, but keep your manners in place.

Thanks,
Paul

Look PMC, we are not really supposed to give out advice to DIY'ers or HO's on this site. To me you seemed like a DIY'er because this is such an easy problem to dignose and your asking us to solve it for you, especially since you claim to have owned an A/C business. think about what the refrigerant is doing in the system and it will all fall into place. we are not trying to be a-holes just to be, we are sticking to the site rules like everyone else should do and trying to get you to come clean about who you really are or if you were ever in the trade or not. If you really are/ were a pro, then apply for pro status here and then you will be less likely to get bashed. sorry you forgot to read the rules before posting. you might want to try and search for the answer to your problem on here since it's been talked about a million times.

[pmc181]

I agree that some people that have all the paper still don't know what they are doing. What I am saying is, I have had techs that install the same size tubing run because they were always showed that in the past. You can't do that. You have to look at the mfg specs to see what size tubing is required to run for the distance between the evaporator and the condensor. Do you agree?

I have also had electricians that alway run a number 10 cable to to Island cooktop because they always were taught to go that. You can't do that either.

Neither of these is right.

In the case of the a/c unit, you need to look at the mfg specs to determine the size of the tubing run so the you really do get the ratings published by the mfg.

In the case of the Island cooktop, you need to look at the size of the cooktop and the distance involved to pick the right size cable due to voltage drop. If you undersize it, you will not get the mfg ratings.

Do you agree with this?

[pmc181]

#18 Today, 08:53 PM
orlandotech

Got it, I understand. I'll apply for pro status. I wondered why all the people jumped in saying things like "Call us an do it right". I have been in the electrical, instrumentation, a/c business for over 30 years. I started at 14 and had my first masters at 19. I had my a/c business for 5 years, and maybe I was lucky but never came accross a unit that gave me the readings I posted. I was looking for some advice because it made no sense to me.

A lot of a/c techs I have seen, simple pump up a unit with freon until the suction line sweats and this in not always correct.

Thanks for you comments,
Paul