HVAC functional equivalent of Heath.com

[latichever]

(Oops hearth.com)

I have questions re upgrading my older central AC system to a newer system--from R22 refrigerant to r410.

One company said I'd not only have to replace the compressor but also the copper tubing and the coil in the air handler. Practically the only thing I'd have left would be the ductwork. And it would cost me almost as much as the original install in 1998.

I've read that this total retrofit may not be necessary.

Is it even possible to buy a new but older generation compressor unit? I've had a couple of electrical problems in the past couple of years--a blown capacitor, and some burnt out wiring. Don't mind spending a few hundred occasionally to keep it going, but it can't last forever.

Any thoughts here or links to other resources would be appreciated?

 

[semipro]

http://hvac-talk.com/vbb/

 

[STIHLY DAN]

You can get dry 22 units, but you would have to change metering device. best long run bet is to bite the bullet and replace the unit.

 

[Ashful]

Damn... now I'm hungry.

 

[blades]

Every time they change to a different fluid for ac the efficiency goes down ( thanks EPA) Metering internal to the systems is different with the 4xx stuff than the 22. Might even need a larger unit vs the 22. Also the two suppliers for the valves are both having problems with valve stem sealing over the past 5 years- they might have got it corrected by now as far as new shipped equipment is concerned but anything sitting in a warehouse for any length of time is suspect.

 

[latichever]

Fortunately, there's been no leaking. The problems have been electrical--a blown capacitor, and couple of years ago, some burnt out wiring this year. The system works well as far as the cooling goes. So my inclination is to nurse it along.

But I'm wondering if there are options to retrofit to 410 that don't involve all three of: compressor, copper tubing, and air handier coil. And how to find someone who can assess my needs who won't be eager to sell me everything he possibly can.

 

[woodgeek]

AC systems are pretty simple tech. A couple coils a compressor, an orifice and two copper lines. In principle, only the compressor really cares about the refrigerant (puron has much higher operating pressures than R-22). So long as the copper tubing is strong enough to handle the pressure (it probably is) and has the diameter to meet the specs of the system (probably is) it will 'work'. Heck, you can get an R-22 system, fill it with propane and it will 'work'.

But if you want longevity and efficiency, you should have a properly engineered system. Shop your HVAC guys and have them try to explain it to you and make a call. There will be 'hacks' that will do any monstrous thing you want, even if it is ill advised, to get the low bid and your business. Not a savvy choice.

My concern is the oil. R-22 and Puron systems use different lubricant, and the oil does circulate with the refrigerant, and gets collected by the system and redistributed to the compressor. Is any of that old R-22 oil held up somewhere in the lineset or coil? Will it end up mixing with the oil in your new $$ compressor you want to last forever? Will this cause the compressor to fail before your hack HVAC guy is long gone? No. Could it shorten its life 10 years from now...you bet.

If you are going to Puron, get a new lineset and indoor coil. Compare the price with getting a whole new system and make a call. IF you are in heavy AC country, 17 years might a be long time. IF you are in Minnesota, its a different call all together.

On the bright side, you still have an ozone layer.

 

[DIrtyJersey]

You can use the line set. It will have to be flushed. R-22 runs totally different pressures then 410A systems. You can still get R-22 condensing units and Evap coils. If replacing the outside unit, with a more efficient R-22 you can install an external TXV valve and fore go the piston metering device you currently have. But still can use a higher efficent R-22 with existing set up. R410A systems evap coils are taller. So fitting one might need some sheet metal work. Outside unit will be considerably bigger due to seer rating mandates. It will be cheaper for you to replace the R-22. On the street the change over from R-22 to 410A will cost you a nice piece of change not unless you have a friend that could do work or get at his or her cost.

Blown capcitor's happen all the time. especially during hot spells. Power surges. The unit working its ass off. Also if the bearings are going in the condensing units fan. You can also install a hard start kit. Which is another capacitor with a potential relay on top to give a weak compressor a kick in the ass to start up easier

 

[DIrtyJersey]

I'm a member on that forum. And they have field days with homeowners looking for help. It's sad.