Oh, Spit! AC unit goin' down...

[Carbo]

Well, it's official. Here it is, July, south Florida, and the old AC unit decides to go to its final resting place. Not quite yet, but the signs are there. The temp in the house can't get below 82 for the past three weeks or so. The damn compressor never shuts off, and I have the soaring electric bills to prove it. It's about eight years old, so putting it all together tells me I need a new AC system.
Through tears, (or is it sweat?), what can I expect to pay for a compressor and air handler, plus installation? I figure I need a four ton unit, and I think a high efficiency model is the way to go.
So, who is the resident AC guy here, and what kind of ATOT discount can I expect? Thanks, guys!

 

[Eli]

LOL, you don't need a new one if it was working fine before.

Call an A/C repair tech....

A recharge, cleaning and replacement of any worn components would certainly be but a small fraction of the cost of a new one.

Edit: Err, unless you want a new one and have just been waiting for an excuse, I guess.

In that case, I have no idea.

 

[iamwiz82]

I'll say just the opposite. An 8 year old AC unit in S. Florida is going to have had a very hard life and probably needs to be replaced completely.

 

[nakedfrog]

4 ton unit? How big is your house?

 

[Carbo]

Actually, Eli, I just got off the phone with an AC guy I've known for about six years. He's repaired my existing unit twice in that time. After I explained to him the symptoms of what is happening, he had me check a few things myself while he walked me through it on the phone. His conclusion is the old compressor is starting to fade. Although he is certainly open to coming here for a look-see himself to verify.

 

Check to see if a mouse popped out. If so, you're okay.

 

[conjur]

Originally posted by: jumpr
Check to see if a mouse popped out. If so, you're okay.

:thumbsup:

 

[Carbo]

I'll say just the opposite. An 8 year old AC unit in S. Florida is going to have had a very hard life and probably needs to be replaced completely.

Indeed. These rigs are workhorses almost year round.

4 ton unit? How big is your house?

I'd estimate it at about 1,400sf. But it isn't only the size of the house, it's the layout, number of windows, insulation, etc. Before I settle on a specific size, I'll have one or two estimates. I'm just estimating myself for the time being.

 

[Eli]

I would think that even a new compressor would be less than a whole unit..

But I suppose when comparing a newer model to an 8 year old unit, there are probably a lot of incentives to upgrade if you're going to have to shell out any significant ammount of money anyway.

 

[drnickriviera]

Originally posted by: Carbo
Actually, Eli, I just got off the phone with an AC guy I've known for about six years. He's repaired my existing unit twice in that time. After I explained to him the symptoms of what is happening, he had me check a few things myself while he walked me through it on the phone. His conclusion is the old compressor is starting to fade. Although he is certainly open to coming here for a look-see himself to verify.

What did he have you check? Sounds like it's just low on freon. Is the compressor making more noise than usual? Does the large diameter copper pipe have condensation on it or is it dry? Any ice on the outside unit?

 

[bunker]

4 ton sounds a bit big for 1400 sq/ft. Make sure you don't over size, you'll never get the humidity out of the house.

 

[Carbo]

Originally posted by: drnickriviera

Originally posted by: Carbo
Actually, Eli, I just got off the phone with an AC guy I've known for about six years. He's repaired my existing unit twice in that time. After I explained to him the symptoms of what is happening, he had me check a few things myself while he walked me through it on the phone. His conclusion is the old compressor is starting to fade. Although he is certainly open to coming here for a look-see himself to verify.

What did he have you check? Sounds like it's just low on freon. Is the compressor making more noise than usual? Does the large diameter copper pipe have condensation on it or is it dry? Any ice on the outside unit?

No ice on any line or on the air handler coils. A lot of condensation, though.

 

[franksta]

What brand/model is it?

 

[Eli]

Originally posted by: bunker
4 ton sounds a bit big for 1400 sq/ft. Make sure you don't over size, you'll never get the humidity out of the house.

Huh.

An A/C removes humidity from the house. Wouldn't having a larger than necessary unit just do it that much better(read: be overkill)?

 

[drnickriviera]

Originally posted by: Eli

Originally posted by: bunker
4 ton sounds a bit big for 1400 sq/ft. Make sure you don't over size, you'll never get the humidity out of the house.

Huh.

An A/C removes humidity from the house. Wouldn't having a larger than necessary unit just do it that much better(read: be overkill)?

No, a larger unit will turn on and off more times, not allowing it to pull the moisture from the air.


Humm carbo. Do you have a split system or is everything outside?
When the system is on, can you feel air from the register at least 2' away? I'm wondering if it's an air flow issue. On some of my rental properties, the inside unit is on ground level, not in the attic. I have a hard time getting my tenants to change the air filters, dust is getting past the filter and clogging the A coil. It's not much of a problem when the unit is in the attic, as it's harder to pull the dust up that high.

edit, I was talking to my brother and he agreed with bunker. 4 tons seems a bit oversized. rule of thumb is 400-500sqft per ton. Unless you have a lot of sun load.

 

[Carbo]

drnick, you may very well be right about a 4 ton being overkill. I guess I'm thinking that because the existing unit, (and I'm guessing it's a 3 ton, but can't say for sure because the model number and specs are faded off), isn't cooling too well, a larger unit is required.
Also, it's a 20 year old house, and here in south Florida that means little to no insulation in the attic and walls, and single pane windows. So we're not exactly energy efficient. But I'll listen to what the contractors have to say about that. I'm going to have an estimate or three on the job, and I'm sure they'll give me their recommendations.
It's a split system, by the way, with the compressor outside at ground level, and I am diligent about changing the filters. Once a month they are replaced. Air flow seems fine. Sure would be nice to know the system simple needs a recharge, but I'm not too optimistic about that.
Outside weather conditions are 91 degrees with 55% humidity. The thermostat is set at 78 degrees and the unit has been running since 9:00AM. The inside temp has been increasing steadily and is now around 83 degrees. Something isn't up to snuff...

 

[Carbo]

Originally posted by: franksta
What brand/model is it?

It's a Rheem, with a SEER of 11.0

 

[Lounatik]

I ued to do AC work in S.Fla and I think that a 4 ton unit is just about fine for that size house. Its about the same as the one I had in mine. AC's dont just fade away, there is definitely something wrong with it. Now, you could have a leak as mentioned above.Central ACs have Schrader valves(like the air fittings on your tires) to put the freon into the system. These valves have rubber O-rings in them that dry out over time and allow freon to leak slowly out.You do not notice the reduction of cooling until you get a few nasty hot days in a row.

If your compressor has bad valves, you wouldnt have any cooling at all,kinda like a car engine with no compression.

Florida and its notorious humidity are a big reason for algae to grow in your evaporator coil(the unit most likely in the house,where the filter is) I used to do many house calls to clean out the evap coil. Its really nasty, and if you are restricting airflow, you will have less cooling.

You said that the unit is sweating all the way back to the compressor? Its not broken. The compressor is doing its job. It may also have a dirty condensor coil.

You say you change the filters regularly.Good, that is number one on the to do list for ACs.

If I were you, I would get your friend to come over and thoroughly clean the coils and oil the fan motors, if needed, and check the charge on the unit.Like I said, sweating all the way back is a very good thing,so you shyould not be out too much on this one.


Peace


Lounatik

 

[Eli]

Originally posted by: drnickriviera

Originally posted by: Eli

Originally posted by: bunker
4 ton sounds a bit big for 1400 sq/ft. Make sure you don't over size, you'll never get the humidity out of the house.

Huh.

An A/C removes humidity from the house. Wouldn't having a larger than necessary unit just do it that much better(read: be overkill)?

No, a larger unit will turn on and off more times, not allowing it to pull the moisture from the air.

Ahh! That makes sense. Never thought about it that way.

 

[dartworth]

4 ton unit for a 1400 sq/ft house...that seems a bit oversized...

i just installed a 2 ton unit for about 1200sq/ft...works great

 

[flot]

I'm not an A/C expert, but I think a slowly reduced cooling capacity is actually probably the BEST kind of failure to have. At least you know most of the components are working fine!

A/C systems are really pretty simple. However, the sizing of them is not - it needs to take into account all kinds of variables. Do a search for HVAC-Talk (a huge A/c repair forum) and look on their for their software sizing tool. Get that kind of info ahead of time so you'll know what the estimates you get are all about.

As someone correctly pointed out - having too big a unit can be just as bad as too small. You don't want it to turn off and on constantly, it needs to stay on a certain % of the day to remove humidity. Your insulation, windows, ductwork, etc will all come into play.

Honestly it sounds like the system just needs to be recharged, and somebody needs to figure out where it is leaking from. Do it soon, before all the refrigerant leaks out!

PS: I have an ~1100 sq ft house - old, concrete, no insulation, and I *believe* I have a 2.5 ton system, which runs a lot but is mostly fine... this month has just been ridiculous. (oh and I'm in Ft. Lauderdale)

 

[Eli]

Originally posted by: flot

PS: I have an ~1100 sq ft house - old, concrete, no insulation, and I *believe* I have a 2.5 ton system, which runs a lot but is mostly fine... this month has just been ridiculous.

Wow, sounds like our house.

Except we don't have any A/C system at all, lol.

 

[Ronstang]

Originally posted by: Lounatik
I ued to do AC work in S.Fla and I think that a 4 ton unit is just about fine for that size house. Its about the same as the one I had in mine. AC's dont just fade away, there is definitely something wrong with it. Now, you could have a leak as mentioned above.Central ACs have Schrader valves(like the air fittings on your tires) to put the freon into the system. These valves have rubber O-rings in them that dry out over time and allow freon to leak slowly out.You do not notice the reduction of cooling until you get a few nasty hot days in a row.

If your compressor has bad valves, you wouldnt have any cooling at all,kinda like a car engine with no compression.

Florida and its notorious humidity are a big reason for algae to grow in your evaporator coil(the unit most likely in the house,where the filter is) I used to do many house calls to clean out the evap coil. Its really nasty, and if you are restricting airflow, you will have less cooling.

You said that the unit is sweating all the way back to the compressor? Its not broken. The compressor is doing its job. It may also have a dirty condensor coil.

You say you change the filters regularly.Good, that is number one on the to do list for ACs.

If I were you, I would get your friend to come over and thoroughly clean the coils and oil the fan motors, if needed, and check the charge on the unit.Like I said, sweating all the way back is a very good thing,so you shyould not be out too much on this one.


Peace


Lounatik

You are the only one in this thread that knows what he is talking about. An eight year old unit is only about halfway through it's expected life, even in Florida. I live in Houston and our two units are 16 years old and are just fine.....because I service them every year.

Like said, you might need to clean the evaporator or the condenser. Look at your outside unit and if the coil is dirty at all clean it with a hose to clear away any debri. You could have mold/algae in the condenser but that is more difficult to clean as you have to break the aluminum sealing tape and use a coil cleaner that mixes with water....although you can still do it yourself.

Most importantly it sounds like you need to have the refrigerant charge checked and probably add some R22. I add some every year to both of my units. They do not tend to leak too much when in use but sitting during the winter takes it's toll. If you do not have the gauges and access to the R22 then you need to call an AC repair shop to come give you a checkout.

 

[Eli]

Originally posted by: Ronstang

Originally posted by: Lounatik
I ued to do AC work in S.Fla and I think that a 4 ton unit is just about fine for that size house. Its about the same as the one I had in mine. AC's dont just fade away, there is definitely something wrong with it. Now, you could have a leak as mentioned above.Central ACs have Schrader valves(like the air fittings on your tires) to put the freon into the system. These valves have rubber O-rings in them that dry out over time and allow freon to leak slowly out.You do not notice the reduction of cooling until you get a few nasty hot days in a row.

If your compressor has bad valves, you wouldnt have any cooling at all,kinda like a car engine with no compression.

Florida and its notorious humidity are a big reason for algae to grow in your evaporator coil(the unit most likely in the house,where the filter is) I used to do many house calls to clean out the evap coil. Its really nasty, and if you are restricting airflow, you will have less cooling.

You said that the unit is sweating all the way back to the compressor? Its not broken. The compressor is doing its job. It may also have a dirty condensor coil.

You say you change the filters regularly.Good, that is number one on the to do list for ACs.

If I were you, I would get your friend to come over and thoroughly clean the coils and oil the fan motors, if needed, and check the charge on the unit.Like I said, sweating all the way back is a very good thing,so you shyould not be out too much on this one.


Peace


Lounatik

You are the only one in this thread that knows what he is talking about. An eight year old unit is only about halfway through it's expected life, even in Florida. I live in Houston and our two units are 16 years old and are just fine.....because I service them every year.

Like said, you might need to clean the evaporator or the condenser. Look at your outside unit and if the coil is dirty at all clean it with a hose to clear away any debri. You could have mold/algae in the condenser but that is more difficult to clean as you have to break the aluminum sealing tape and use a coil cleaner that mixes with water....although you can still do it yourself.

Most importantly it sounds like you need to have the refrigerant charge checked and probably add some R22. I add some every year to both of my units. They do not tend to leak too much when in use but sitting during the winter takes it's toll. If you do not have the gauges and access to the R22 then you need to call an AC repair shop to come give you a checkout.

I don't really know what I'm talking about, but at least I tried....

And if Lounatik's post is correct, then at least my first post wasn't completely wrong.

It just didn't seem right that he would need an entirely new unit because of some diminished performance. That's kinda what A/C's do ... you just gotta keep up maintenance.

 

[Ime]

I'm going to answer the question of a new 4 ton AC.

The wife and I bought a brand new 4 ton HE Trane Split Heat Pump Unit. The 19 SEER model. Yeah, top of the line.

It cost us $8,500. It comes with a ten year warranty on all parts and labor. Needless to say the warrenty is built-in to the price.

So, if you want a new 4 ton system A/C it may cost you less. I believe A/C's are a little cheaper than Heat Pumps.