Why?

Eugene Silberstein 3

In new territory, the one variable that always factors in as a major contributor to the accurate answers to your questions is time.

One of the questions posed in this thread was, "Will it work if we mismatch the evaporator coil and the condenser?"

Well, we all know that, to a certain degree, the system will work, as this has been done ever since there were different evaporator coil and condensing unit sizes. How well these systems operated depended on the same factors that affect the oepration of systems today: Proper installation, evacuation, charging, etc.

Now, the issue that comes up more often than that of whether or not the system will operate, is whether or not the manufacturer will honor the warranty on mis-matched equipment. The only person (or group of persons) who has this answer is the manufacturer.

So, it appears that, in order to answer this question accurately is to wait and see what each individual manufacturer does. I have heard from one manufacturer's rep that, if there is a problem with a new or relatively new condensing unit, the make, model and serial number of the air handler will also have to be supplied in order for the return.excange to be processed.

This can come back and bite a manufacturer in a very sensitive spot, if this particular manufacturer is out there by himself. For if this guy is the only player in town that is requiring this information and not honoring warrantees because of mismatched components, service and sales companies may very well steer away from this equipment in the future. I can guarantee that the manufacturers are watching each other very carefully to see what the next guy is doing. None of these fine companies want to be the odd man out.

Also, whose fault is it that the equipment is mismatched? is it the salesman who figured that a smaller sale is better than no sale at all? Is it the homeowner who has limited funds and cannot afford to replace the entire system? Is it the conditions of the installation itself that cannot accomodate the new, larger sized equipment, especially since the original, smaller air handler fit perfectly into that utility closet?

Time will tell my friends.... Time will tell.... Boy will it tell!

don_163

Why?

Ok lets hear it..What are the reason you can not install a
13seer on a older coil?

I've herd...not ari rated.Can never dail in your subcool or superheat temp.Will constantly have too recover or add freon depending on season because of a refrigerant imbalance.Companys will not stand behind the warranty.

And then I herd just the other day in the supply house...
If you install a txv all is well.Ha.

And then...you hear from other that lots of manufacturers or
putting in smaller blower to get their ratings..
Then the equipment can not produce enough esp and most system are only seeing 250 to 300 cfm per ton only.
Which drop the efficency even less then what was in place
to began with.

I'll tell you this much..I'll sure be happy to finally have pressure enthalphy in my tool bag..so I can find out for myself what the real answer are.

And then!

RadPro

Same Question myself!!

> Ok lets hear it..What are the reason you can not

> install a 13seer on a older coil?

>

> I've

> herd...not ari rated.Can never dail in your

> subcool or superheat temp.Will constantly have

> too recover or add freon depending on season

> because of a refrigerant imbalance.Companys will

> not stand behind the warranty.

>

> And then I herd

> just the other day in the supply house... If you

> install a txv all is well.Ha.

>

> And then...you

> hear from other that lots of manufacturers

> or putting in smaller blower to get their

> ratings.. Then the equipment can not produce

> enough esp and most system are only seeing 250 to

> 300 cfm per ton only. Which drop the efficency

> even less then what was in place to began

> with.

>

> I'll tell you this much..I'll sure be

> happy to finally have pressure enthalphy in my

> tool bag..so I can find out for myself what the

> real answer are.

>

> And then!

RadPro

Same Question Myself!!

Love that name!!

When I purchased my evap coil two years ago that question was asked. Do you want the 13 Seer coil or the regular one? I like what are you talking about? The counter just said that is what is coming. I was putting in a 12 seer anyway so I said the regular. After sizing the house, I only needed a 3 ton and had purchased a 4 ton evap coil. I am thinking why can't I put a txv on this coil when it needs a 13 seer change out but oh well, the house is being sold and I don't think I will have to worry about it now!!

In the past I now you would have to upsize the evap coil acording to the ari manuals to acheive 12 from 10 or 11 seer with orfice or just add txv.

Time will tell and did you catch that article in "The News" from the ceo's off major oems that they rethought that warranty deal. Can you really blame the homeowner if someone scamed them on a cond. only change out?

Don in SEIA, Soon to be from middle MO.

jim lockard

I think

we had a very workable system with the flow check piston indoor coil. We shall see how this new equipt. is going to work out. Best Wishes J.Lockard

John Mills_5

Older coils...

were smaller, designed for a higher head pressure than what the newest units are delivering. If you put a coil designed for 8-10 SEER on a 13 SEER outdoor unit, likely you'll have to overcharge the system to get enough refrigerant flow through the fixed meter in order to properly cool. Overcharging uses much more juice killing SEER and also shortens the compressor life. Yes, adding a TXV will help but if you've see the new line of coils all the mfrs have brought out, you'll see just how much larger they are. So even slapping a TXV on a small coil probably won't get you up to 13 SEER.

Like having an old 3 speed tranny on a nice new DOHC engine. It will get from point A to point B but won't be up to what that car could do with a new 4 or 5 speed tranny with electronics set to shift at the best points for that engine. Coils are matched to outdoor units.

Paul Fredricks_3

ROI in the northeast is pretty long. SEER, as important as it is, is not as big a consideration here as it is in more southern areas. If we take the affect on SEER out of the equation we're back to the basic question; Can it be done, will it work, will it hold up for 10 years, 20 years?

We are in a very transient area. A lot of people expect to move within 5 years, so ROI is not as much a factor as having a system that will cool the house when they go to sell it.

Kniggit

not just the north east

We have that problem here, in the Midwest. Selling upgrades on new homes and repairs is often hard to do, either people are on a fixed income (retired) or have no intention of staying more then 5 years, often as little as 1. Selling high efficiency equipment was impossable to my sister, she built a house $100,000 over the rest in the sub-division and said to me, "Why spend more money on that? Its just a 5 year house."

Jeff Lawrence_25

I don't know how valuable this will be

Several years ago, I bid on (and won) a cooling only install, 2 ton, 12 SEER. I picked up the equipment and installed it the same day. Rheem RAMB condenser with a matching AllStyle coil and TXV.

I got called back out there every 3 weeks. It was freezing up. I'd defrost it and check the charge. The furnace was reasonably new and had a 3 ton drive on it, but I changed the motor in case it was cutting out. I replaced the TXV. I recovered all the refrigerant, installed a 16 cubic inch drier, evacutated the (you know what) out of it and recharged it with virgin refrigerant.

Every three weeks, I got the call.

I finally filled out the AC data sheet (attached to the is post) and sent it into the tech gent at the wholesaler. Hecouldn't find anything wrong with the numbers I filled out, so we met up and we both went out and looked at the system. He removed about 6 ounces of R22, changed the blower speed (up or down, I don't remember) and said it was perfect. He gave it his blessing and told the homeowner it was good.

Three weeks later, I got another call. Frozen up again. They wanted their money back

I called the wholesaler. The tech guy called me back and we met out there again. He could tell the lady of the house was unhappy and then he made THE discovery.

When I picked up the equipment, I got a 2 ton condenser, 2 ton coil and a 1.5-3 ton TXV. It should have been a 2.5 ton (or 3 ton, I can't remember) evap coil. As I recall, the surface areas of the condenser and the evaporator need to match up. Even the ARI ratings of the 12 SEER condenser call for a larger (AllStyle) coil with the 12 SEER condenser.

The tech guy got me the correct evap coil and I changed it out. Except for routine spring and fall check-ups, I haven't heard from the homeowners again.

My stomach did clench up a bit around the three week mark when the phone would ring....


ON EDIT: Gents, I totally lost what I ws trying to say. My point was that they gave me a 10 SEER evap coiland I needed a 12 SEER coil. True, the 12 SEER coil was only a larger tonnage (more surface area) coil, but it didn't match. I had problems. What problems may we have with consumers that don't want to change the evaps?

Empire_2

Jeff

Thanks so much for that nice sheet that you posted. I love the thing. It beats drawing a picture like I have been doing which, ( I cannot draw to well) is usually very messy. ;-) Thanks again.

Mike T.