Calling All Heat and AC Gurus

Option 2 is your best bet - you can get the 2 1/2 ton unit cheap, and the install is easy, max 2 hours labor. Check your roladex and find a friend who does commercial buildouts, ro homebuilding, or knows someone who does.

Gotr a 3 1/2 ton heatpump with 5 year warranty from a homebuilder's GC last summer, $850 installed. Came from foreclosed new construction on an M & M lien,

Helps if you speak Spanish, of course.

Sounds like a sweet deal Ktel - don't have that kind of Hispanola' network!

CU,

I shopped for and bought my home HVAC system a few years back, and from what I remember, I think you may find that to get the 13 seer you are looking for, you are going to need a new A-coil (evaporator). Most of the older 10 seer and under combinations that are installed used an orifice based A-coil, and the newer, higher efficiency setups use a TXV, which is a Thermostatic Expansion Valve. So, in order to get the efficiency I wanted, I had to replace the A-coil along with the outside unit. For what it's worth, the A-coil cost is low when compared to the cost of the outside unit. YMMV (your mileage may vary, usual disclaimer).

Tom

Thanks tdesmit - found out quickly about the Evap issue - looks like we've got a couple of options - thanbks!

If there is a building authority over the area, they may not allow mis-matched indoor/outdoor combinations. It is hard to get the match close enough for good efficiency and newer R-410A condensing units cannot be connected to older R-22 coils because of higher pressures of R-410A. I would only do 1 or 3. Compressor only parts cost should be about half of complete outside unit. Higher efficiency equipment may save enough on utilities to be worth a good look. Usually 15-17 SEER is not bad expensive. 22 SEER gets ridicules. -- JHF

Thanks CB - found out our codes kick-in April 1st to also add the element for whole-house evaluations - meaning that the home has to be audited before the proper system will be approved for installs.......gubmit ain't going to tell me what to do on this one though - I'll beat the deadline

Yep 1 & 3 are looking like the fix right now...(although I ams till chewing on 2)

thanks!

By the timming of your question, I will assume that this is a heat pump. Regardless, the sound you hear w/screwdriver to the ear would not be my biggest concern, unless the unit is not cooling/heating? The unit running all the time would be. Try this with the unit running and w/screwdriver to the ear, bump the compressor w/ the palm of your hand rather hard a couple of times. If the noise changes while you do this the suction valve in the compressor is bad (usually you can hear a bad valve w/o a screw driver, by a faint metalic "tic,tic,tic",which will change when you bump the compressor w/ your hand). In which case the unit will not be cooling/heating, no suction line sweating/hot to touch. And you would not be so sure about the charge being good.

Personally, I would replace the condensing unit only w/ like, unless you can get tax write off for a unit w/ a higher SEER. While your at it you may want to move up to a 3 ton if your indoor AHU has the capacity. Like I said before, my biggest concern would be the unit running all the time.

Remember, "there never seems to be enough money or time to do a job right the first time', but, 'there aways seems to be enough to do it over"

option 2 is not possible. There simply arn't any more R-22 Condensers, they dont make them anymore. unless you find one in a warehouse burried you will not get one. you can thank the new guidelinse for that and all of the manufactures are more than happy to sell you air handler and condenser in a R410-a.

Thanks Guest, but fortunately we do have some older R22 units around here, just want to retro-fit to an acceptable situation - NOTE: the guys who habe thme, move about 8 units/week

There are many reasons for your unit not cooling.Check your system pressures.Check your super heat and sub cooling temperatures.These numbers will tell you if you have a clogged evaporator, expansion valve, or compressor valve problems.

If you intend to change out the unit, don't go half measure.Buy the highest SEER you can find and replace the inside and outside units. If you are not a qualified A/C tech, you cannot charge the system.Need to be licensed.

Not the cheapest.....but the best investment.....is a change out/upgrade to a 15 SEER R410 system.

Goodman (Generic Amana system with a copeland scroll compressor) has one with a 10 year parts and a life time compressor.

Goodman SSZ14

Hi Markar - yes, am also considering this Mfg'r - it appears we have 2 local contractors who are doing a lot of installs on the Goodman's - the warranty sells itself so they say...can't wait to run the numbers

Nice piece Zgolf!. One thing you mentioned I do not worry about is the future availability of R-22. It will only be illegal to manufacture or import R-22. It will not be illegal to use. What has happened with R-12 and R-502 is a number of very good replacements have come along. The same thing is happening with R-22. I don't worry about it. What I am more concerned with is having a leak free system. Many A/C guys feel like having to "Top Off" the charge is normal. It is not. Insist that the system be leak free. There are known ways of testing and proving a system is leak free. If the tech says he can't guarantee it to be leak free, get another company. -- JHF

Yes CB - contractor here this a.m. said the same thing - he can put in another R22 unit (cheaper) and he also affirmed that R22 is not going away - too many footprints both residential & Commercial

He's also going to quote an upgrade in infrastructure as well

will be ablke to do the math on effficiency paybacks, any rebates, etc

Wow zgolf - many thanks to you for this piece - appreciate the input - about done with all the estimates & quotes, and will add back some final findings & decisions

Stay away........... from variable speeds or any super high end controls.

$$ They're sensitive to power spikes, sags or lightning and they'll kill you on parts. $$

CUTiger,

Sounds like you will be buying some equipment so here's a few more things that I had jotted down during my research. I managed to find my notes.

If you are going to purchase an A/C less than 3 1/2 ton in size then a reciprocating compressor is usually better. The recripicating version is an old reliable that will provide virtually the same or better efficiency. A single stage scroll compressor is all you'll need otherwise. Investing in a two stage scroll is to be reviewed carefully, not because they'll cost more, but you may need to replace both of the compressors if one of the units goes down. On another note, buying a two stage furnace is the way to go.

Stay away from flex ductwork if you are getting new ducting. Their design results in too much static pressure (slows airflow down).

A thermostatic expansion valve (TXV) metering device adjusts the flow of refrigerant based on the load. It does not just meter in an amount of refrigerant (no matter what) like the fixed orifice does. That's why you want a coil with a TXV installed. A non-bleed TXV is best and can increase the SEER rating in some systems (externally equalized TXV).

Have a non-corrosive drain pan installed for a new coil, if you'll be needing one.

You can avoid drilling two holes in your wall if you invest in and are allowed to use a concentric vent kit.

The main installation errors that result in poor effiiciency are improperly charged systems, poor airflow in your ductwork and a mismatched coil and outdoor unit. Poor dip switch settings are also sometimes responsible for poor airflow.

The thicker pleated 4"-5" media filters are the all-around best, if you have option of getting a new filter. The filters are pricey but you only change them about twice a year and they are almost rated as highly as the expensive elctronic/electric versions that may require yearly maintenance by a tech. MERV ratings are used as the quality measurement for filters.

Check your condenser, after it has been installed for a time, for level. Newly dug groundwork can settle the condenser out of level and cause strain, which could wear out bearings and diminsh efficiency.

Ensure that your A/C system will have short cycle protection. Having this enforces a few minutes of delay in between power interruptions.

Outdoor sound of the air conditioner unit can also be measured in bels (0-13). Most units are around 8-9 bels, but good ones go down to about 6.8 bels. The difference between 8 and 9 bels is the sound output of 9 bels = 10 x 8 bels.

Hasta La Pasta (about the only Hispanic words I know).