Air Conditioning problem

[noname]

I live in an apartment building for the last 5 years and my 25-30 year old central air unit died (compressor). Now the unit was replaced with a SEER 10.0 unit and I can no longer get the apartment down below 73-74 even at night. Is this normal?

Now I have done a bunch of Google work over this and I have read the little tube (HIGH SIDE) should be warm to hot to the touch but mine is not. Matter of fact its room temperature at best but the big tube (LOW SIDE) is cold like a soda that was just pulled out of the refridgerator. What should the little hose feel like and if it should be hot what can I tell my maintainence men so they will take me seriously that there is a problem.

With 2-3 computers running in this room 78 degrees F is unacceptable when the previous 4 summers it was 70-72 in here (would get down to 62 easily if I let it at night or 66 in the day).

Thank you for any advice you can offer.

[GETCOOL-MARK]

Hello, no one from the net can see your system. I know you tried to provide good info. Maybe we can go a step at a time.

Take a thermometer and get the temperature difference between the supply air and the return air. temperatures. The temp difference is your Delta-T.

Tell your maint man, "here is my Delta-T reading". Now your using a tech term and sound like you know something.

Report back as needed.

[HVAC IsFun]

An airconditioning system should provide an indoor environment of approx. 15-20 f lower than the outside temperature at the time 'if' it is properly sized and functioning correctly. The last poster gave you a very good way to check the systems effectiveness . Do that, and let us know. Keep in mind, that, if you have alot of heat generating equipment in your apartment, then you may have increased the cooling load beyond what the system is capable of .

[noname]

So, if its 100f outside best I can hope for is 80?

What I used to get was 70 no problems. What if its 70 outside shouldn't the air conditon get to 60 or less?

[Travis Jordan]

I think the PP meant to say that "an air conditioning system should provide an indoor environment supply temperature of approx. 15-20 F lower than the indoor return temperature at the time 'if' it is properly sized and functioning correctly."

[Stormin Mormon]

So, if it's 100F in the apartment, the air coming out of the vents oughta be about 80.

Also depends on humidity. If the air is very humid, you will get less temp drop because the system is using a lot of power to remove humidity.

I'm sorry we can't be more help. I'm thinking at this point that you might have an under sized system, wrong orifice, wrong ammount of freon in the system, or any of a list of things. All of them take a technician to do much about it.

Wish I was more help.

[noname]

Here is what I am fighting with the maint dept over (all different degrees of HVAC certifications).

#1 - When the outside unit was changed the evap coils were not (they simply do not change them in any units in the 5 years I have been here) yet this complex is 30 years old as was the now defunct unit. #2 - the HIGH SIDE (small tube) is not even hardly warm but the upstairs unit is. #3 - the compressor when running has beads of condensation on top of the unit (as well as the normal sweat). #4 - Its a 2 ton unit and this apartment is 1540sq ft (1400sqft livable space...thats minus the master closet that is sealed and the sealed utility storage room)

What can I tell these guys to make them make this right?

Btw: Thanks for all of this help.

[Stormin Mormon]

Just from what I'm getting here, I'm wondering if there is a partial restriction of the orifice. This isn't something a home owner can check -- takes some tools and training. But it would give those symptoms.

I hope they installed a new filter drier in the liquid (small) line.

[noname]

I stood outside and watched everything they did (still sunburned) for the 3+ hours it took them and YES that was brand new dryer unit they had to weld into place.

[Rein]

15-20 F lower than the OUTSIDE temp ?? I must have some miracle system, it easily gets it to 75 when it's 120 outside (Arizona) Or did you mean the difference in temperature between intake in ac system and output ??

Remove NO-SPAM from email address when replying

[CBHVAC]

Then there is part of your problem, as a 30 year old evap is not even close to being matched to a new condensor. Thats a given.

That might point back to the fact that the metering device in the evap coil wont be matched to the condensor. It also might be the wrong size lineset for a newer unit. Each make specifies the correct lineset sizes for the condensor, when matched to a MATCHING evap.

Thats not a good sign. Can you scream overcharge at the guy that installed it? Also, you dont WANT the compressor sweating. IT COULD again point back at the evap coil, and thats probably 60% of the problem. the other 40 is charge conditions....

Have them check the superheat, or subcool, depending on the metering device in the evap. IF they have a clue, they will know what that is...there is a chart on all modern units on the access panel to the condensor that will have the correct chart.

[CBHVAC]

Wrong. GOD Chris...when will you learn to shut up abou tthings youdont know about?

[noname]

The indoor evap coils is not modern and nothing can be read on it anymore after 30 years. :(

I think I am sunk as for as this tard place but I will ask them what you said.

[CBHVAC]

Wont matter. The superheat, subcool, and/or hot gas discharge temps will be on the OUTDOOR unit. Its new...so there is the information that a tech that has a clue will need...to get started. In order to properly charge a unit, he needs to know the wet bulb temp indoors, the indoor ambient, the outdoor temp, and he can, IF he knows what he is doing, can charge the unit with nothing but a hose from a jug of refrigerant and a good thermostat, reading the temp on both lines back to the outdoor unit. Slapping a manifold on the outdoor unit till he gets above 58.6PSI on the suction side is WRONG.

I know the feeling. I just faxed over a copy of an estimate for taking over the preventive service on a large company here...we actually DO what we say, and after spending 4 hours there just looking these units over, its obvious as hell that the company that was servicing them is a crook. They were getting $5600 a month..(cheap actually for these units...air filters alone cost wholesale over $2200) and they look like they have never been touched. Shame too, since they probably think they are in GREAT shape, and wont like my estimate of 6200....but hey...in this biz, if you have someone that has a clue, do you get what you pay for...

[American Mechanical]

A restriction causing a low superheat? I think there may be a mismatch, possibly insufficient coil size OR plugged A-coil - something in this equation isn't right and it's awfully hard to tell from here.

- Robert

[noname]

Yeah, an all of these einsteins have their hvac certs, wtf?

Anyways I printed out your info and am ready to slam this mofo as I am tired of being hot.

[noname]

Just wanted to let everyone know that they said my coils were fine (cut me short before I could even finish my sentence) and all it needs is more freon.

So, I hope they blow this mofo to kingdom to come and wondering if there is anything I can do to help it along so it blows itself to hell?

I really have a short fuse when I am dealing with idiots who refuse to listen to the manufacturer and to sound logic (both had the same conclusion).

Basically I hope while I am gone they fill up my unit as they are supposed to and by tomorrow it goes KABOOM.

Once again thank you everyone who offered help I listened and learnt but the powers that be could care less.

[CBHVAC]

Ok...first of all, what is the brand and model number on the unit...( please tell me its a York, Coleman, Fraizer Johnson, or some other UPG brand..then I can send you the installation instructions you wont EVER see) If its a Goodman, Janitrol, or GMC, all the same, I have the dealers manual for that as well... IF its a Carrier, or like brand, Payne, Bryant....I have those...

BTW, if its sweating at the compressor, thats not a good thing, and if they add more to it, well....you might get your wish..:)

[noname]

I don't know if they made it around here after wasting my entire day as they had 9 other units to overfill before they got to mine.

As for a model its a Goodman CKL24-1K

[~KJPRO~]

Just a new LL drier eh Stormin??

We're talking about a condenser change out, not a complete new system.

~kjpro~

BTW, new condenser on a 30 year old evap is just crazy and inefficient.