home HVAC question...to charge or not?

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Got an older 2.5 ton Trane HVAC, R-22. Where I work, I constantly hear about the problems with 401a systems and not just ready to change it out. About 4 years ago, it developed a leak on one of the condenser tubes. HVAC guy found it, welded it, pressure tested it, and the recharged with R-22...boy that was expensive. Fast forward to now. Still working fine but I can tell by the sound the expansion valve makes and how long it takes for that sound to go away, it probably needs a shot of R-22. My question....should I pay the bucks, I know R-22 is stupid expensive now, and have it "topped" off or if it ain't broke, don't fix it. Thinking too that if I had more Freon, will that increase the pumping pressure and maybe contribute to another leak?
 
Schmoe - Do you think the HVAC guy didn't charge it properly or that another leak developed?
 
I'm pretty sure he did. He came recommended from a good friend of mine that has used him past and trusted him. I would think that if another leak had developed, it wouldn't be working at all by now. It blows ice when it's running, hence my dilemma....
 
With the price of r-22 you’d be better off with a new system with whatever the new refrigerant is. Getting r-22 is always going to be an issue. If you’re set on keeping the system at least fix the leak before charging it. R-22 is probably going to cost much more today than it did 4 years ago.
 
If the outlet of the evaporator is good and cold while running, it is properly charged.

Most of the problems early in the R-410 era were manufacturers trying to repurpose old R-22 coil designs to 410a. They could not take the higher pressure.
 
Originally Posted By: Schmoe
Got an older 2.5 ton Trane HVAC, R-22. Where I work, I constantly hear about the problems with 401a systems and not just ready to change it out. About 4 years ago, it developed a leak on one of the condenser tubes. HVAC guy found it, welded it, pressure tested it, and the recharged with R-22...boy that was expensive. Fast forward to now. Still working fine but I can tell by the sound the expansion valve makes and how long it takes for that sound to go away, it probably needs a shot of R-22. My question....should I pay the bucks, I know R-22 is stupid expensive now, and have it "topped" off or if it ain't broke, don't fix it. Thinking too that if I had more Freon, will that increase the pumping pressure and maybe contribute to another leak?

Have you priced HVAC systems lately? And, being summer is right around the corner, you are a nice catch in an HVAC companies sights. I think I would have it fixed. Unless, it's so old that it might not be worth it. I'm not there to actually see it, so I can only speculate.
Good luck with whatever you decide.
 
"R-22a" is actually nothing but propane. That gas has similar thermal properties to R-22 but of course is extremely flammable.

So if you want to go that route, grab a tank of Blue Rhino and have at it.

Nothing should be charged into a known leaky system. Repair properly or replace.
 
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The leak had been fixed about 4 years ago and once it was charged at that time, it hasn't been touched since. Here in Oklahoma, it got used a lot during the summer and kept blowing ice cubes.
 
Due to declining demand R-22 has dropped in price. I manage inventory and I am seeing prices over $100 less per 30LB jug than a year ago. I have had no trouble buying as much as I need, either. There are several "drop in" replacements, but some of the techs tell me that the reduction in cooling efficiency keeps them from recommending them. I'll bet there is plenty of price gouging going on with R-22 right now. R410A is also significantly cheaper than it was a year ago. I would say it's running 50% of what it cost a year ago when there was a short term global shortage.
 
Originally Posted By: mk378
"R-22a" is actually nothing but propane. That gas has similar thermal properties to R-22 but of course is extremely flammable.

So if you want to go that route, grab a tank of Blue Rhino and have at it.

Nothing should be charged into a known leaky system. Repair properly or replace.


WHAT???????????????
Actually true- I found that out from a buddy of mine who was in the business. He was shocked as well- lol!
 
Do you have a sight glass? Set of gauges? I had the former installed along with a Sporlan TXV back in the mid 90's on my R22 unit. It's currently 28yrs old. It's now over-sized due to all the energy updates I've done over the years. Plus, the t-stat is set above the design point for cooling.
 
Originally Posted By: Kage860
With the price of r-22 you’d be better off with a new system with whatever the new refrigerant is. Getting r-22 is always going to be an issue. If you’re set on keeping the system at least fix the leak before charging it. R-22 is probably going to cost much more today than it did 4 years ago.




There's plenty of R22 out there mainly because it has to be collected. Ebay has 5lb cylinders for $195 shipped.
 
Originally Posted By: AirgunSavant
Originally Posted By: mk378
"R-22a" is actually nothing but propane. That gas has similar thermal properties to R-22 but of course is extremely flammable.

So if you want to go that route, grab a tank of Blue Rhino and have at it.

Nothing should be charged into a known leaky system. Repair properly or replace.


WHAT???????????????
Actually true- I found that out from a buddy of mine who was in the business. He was shocked as well
R-22 is difluoromonochloromethane chemically. Not propane. The pressure-enthalpy curves may be similar, but it's not the same chemicals.

If R-22a is a blend, need to be a bit more careful.

If pure, it's simpler.

I wouldn't want to use propane for a grill due to sulfur based odorants.
 
Schmoe I wonder if your blower fan speed is set right? When you say the system is blowing ice cubes, I assume you mean the evap coil is icing over?

You could use a less restrictive air filter or bump up the blower speed, as a place to start anyway.
 
Sometimes, it is caused by bad capacitor.
Testing capacitor is easy and the tester is cheap on Amazon or Ebay.

Sometimes capacitor is not up to the spec but not bulging yet.
The system usually have 2 or 3 capacitor, 2 run capacitor (Compressor and Fan) and 1 Start Capacitor.

Be careful when testing, make sure the charge is out.
Check Youtube for videos.
 
The unit being r22 I'm guessing is at least 10 years old and out of warranty. To keep it cost effective I would top it off with any cheaper R22 substitute like R407 and see how small the leak is ( I know that the oils of R22 and R407 aren't compatible but it's an old unit and it works). If the leak is too large that perhaps requires a new coil, I would then go with new system and get the 10 year warranty as well.
 
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