Air conditioning situation - at my home - questions.....

[95avblm3]

Originally Posted by Baz

Yo Gorilla...thanks for the post. My situation is fairly straight forward. I was just unsure if I should make the switch to R410A or not and thanks to input from James, Bill, Blue Sky, and Grendiers....it was pretty clear the best approach for me right now is just to replace the condenser unit, which comes complete including drier, etc. All I will have to do is hire someone to do the freon lines and freon for me.

As far as I know you can still change out R22 components as needed. Now if I changed the whole system out - I would need a permit.

Being in Florida I learned a while back it doesn't hurt to have a window unit somewhere in case your central AC goes down. I even went out and bought a second one this week so I'm OK for now and not suffering while the system is down.

I'll provide an update when things are resolved. Good luck with your situation too!

That's cool. Sounds like you got it under control. I agree with the others, delay the switch as long as you can. We are good now... Had a complete system installed right before the 4th of July. The last few nights before they finished the install, we drug our mattress from the bedroom to the living room where the one working wall shaker kept the temp tolerable. I'm looking forward to pulling the old units (1 working and 3 dead) out and patching the walls.

I look forward to your follow up. Best of luck!

[Baz]

I want to again thank everyone for their input and interest. Especially Billy....who is always willing to help Pelicans with HVAC issues.

So here's my followup on my AC issue....

Ended up ordering a new 2.5 ton condenser unit plus an inline Filter Drier from AC Wholesalers. Then I hired a local AC tech to do the install this morning. I had removed the old unit and had everything ready so he could braze on the 2 copper lines, wire up the electric feed (2 wires), and then fill with refrigerant.

The cost ended up $866.00 for the unit and filter plus I paid the tech $300.00 for his time and the refrigerant so grand total was $1,166.00.

I should be set for a while now - the condenser has a 5 year warranty but hopefully I will get 10 years out of it with proper maintenance. We'll see.

It will be nice to sleep in my bed again instead of the living room couch!

I must say though....having the 8K BTU window unit bought me some time to get a suitable plan and solution together. I'm hanging onto it just in case. Best $290.00 I ever spent!

Here's a pic of my new unit.....

[red-beard]

Looks good.

[Baz]

Originally Posted by red-beard

Looks good.

Thanks James and thanks for your help - you were the one who suggested just replacing the outside unit - which was the correct call.

[BlueSkyJaunte]

Glad you got things squared away without paying an arm and a leg.

Lucky you - we have a single one-piece unit...and mounted on the roof. When ours went out in June (!!) I had to buy a portable unit with a window exhaust and we all slept in the master bedroom. It was brutal.

[billybek]

Looks good.

One thing I am a little concerned with is if the unit recycles its heat being fenced in the way it is.

One service call I had was that a 300 ton multiple compressor screw chiller was tripping on high pressure at startup -- sometimes. It was also tripping on high pressure during operation---sometimes.

The installation was such that the air cooled condensers faced east for one circuit and west for another. Their was also a masonry wall that was to knock down the projected noise from the compressors and act as an architectural screen.

The load from the rising and setting sun put on the condensing coils would drive the condensing pressure up by about 75 psi. When the wind conditions were right the hot air off the discharge would be pulled back into the inlet side of the condenser. This would result in a trip.

The customer cut some windows in the brick walls and extended the fan discharge by adding round duct work to the outlet. When it was finished it looked like a brick ocean liner with holes in the hull....

So the point of this long post is to ask you to ensure that the condensers discharge hot air isn't being recycled back into the unit. It will drive up pressures, reduce efficiency and shorten unit life. You may need to check this under various wind conditions.

A simple solution may be to cut out the lower sections of fence and install some chain link to allow easier air flow into the condenser.

Always a pleasure to help out when I can.

[mattdavis11]

Hope it's ok to piggy back on this thread. My brother went the same route a few years ago with his old home, just replaced the outside unit. Being an a/c tech made me curious as to how long it would last. He sold the home shortly thereafter.

When a compressor locks up, and most scroll compressors do eventually, there would be bits of metal carried throughout the system, correct? Did the installer flush the lines and replace the orifice?

It seems to me that it would be necessary to flush as there would be contamination of the oil, and possibly bits of debris remaining in the system if he just replaced the compressor/condenser and the in line drier.

Also, just the same as R12, R-22 can be purchased with a license, however, neither are no longer are allowed to be manufactured in the US. That's why the prices have skyrocketed for both. It is total BS, both refrigerant are more efficient than the successor. Can't have it both ways, but with this you get neither. Less efficient refrigerants will require more energy to meet the desired outcome. So, what is worse, an energy plant emitting loads of pollution to keep up with demand, or a few molecules emitted into the sky.

Question for the gurus. I have a 2.5 ton unit servicing about 1300 sq.ft, #71 orifice installed. I notice that when the temperature outside is higher, my vent temps are lower, eg. it's 80 out and vent temps are 60, when it's 100, vent temps are 55. Would it make sense to change the orifice?

Hope you don't mind my post Baz.

[Baz]

Originally Posted by BlueSkyJaunte

Glad you got things squared away without paying an arm and a leg.

Lucky you - we have a single one-piece unit...and mounted on the roof. When ours went out in June (!!) I had to buy a portable unit with a window exhaust and we all slept in the master bedroom. It was brutal.

I've gone that route before (portable) Blue Sky - not ideal! It's an unwritten rule that AC system only go out in the warm months, you know.

Originally Posted by billybek

Looks good.

One thing I am a little concerned with is if the unit recycles its heat being fenced in the way it is.

One service call I had was that a 300 ton multiple compressor screw chiller was tripping on high pressure at startup -- sometimes. It was also tripping on high pressure during operation---sometimes.

The installation was such that the air cooled condensers faced east for one circuit and west for another. Their was also a masonry wall that was to knock down the projected noise from the compressors and act as an architectural screen.

The load from the rising and setting sun put on the condensing coils would drive the condensing pressure up by about 75 psi. When the wind conditions were right the hot air off the discharge would be pulled back into the inlet side of the condenser. This would result in a trip.

The customer cut some windows in the brick walls and extended the fan discharge by adding round duct work to the outlet. When it was finished it looked like a brick ocean liner with holes in the hull....

So the point of this long post is to ask you to ensure that the condensers discharge hot air isn't being recycled back into the unit. It will drive up pressures, reduce efficiency and shorten unit life. You may need to check this under various wind conditions.

A simple solution may be to cut out the lower sections of fence and install some chain link to allow easier air flow into the condenser.

Always a pleasure to help out when I can.

Thanks Bill - always appreciate your most valuable input and observations. If you ever get down here - dinner and drinks are on me. That fencing has slots in it and under it, but maybe like you said if I cut off the bottoms it may improve circulation. I wouldn't need to add any chain link fencing - just leave it open. This exposure faces west too and bakes in the afternoon. I do plan on putting up some lath overhead one day which would help. Thanks again!

Originally Posted by mattdavis11

Hope it's ok to piggy back on this thread. My brother went the same route a few years ago with his old home, just replaced the outside unit. Being an a/c tech made me curious as to how long it would last. He sold the home shortly thereafter.

When a compressor locks up, and most scroll compressors do eventually, there would be bits of metal carried throughout the system, correct? Did the installer flush the lines and replace the orifice?

It seems to me that it would be necessary to flush as there would be contamination of the oil, and possibly bits of debris remaining in the system if he just replaced the compressor/condenser and the in line drier.

Also, just the same as R12, R-22 can be purchased with a license, however, neither are no longer are allowed to be manufactured in the US. That's why the prices have skyrocketed for both. It is total BS, both refrigerant are more efficient than the successor. Can't have it both ways, but with this you get neither. Less efficient refrigerants will require more energy to meet the desired outcome. So, what is worse, an energy plant emitting loads of pollution to keep up with demand, or a few molecules emitted into the sky.

Question for the gurus. I have a 2.5 ton unit servicing about 1300 sq.ft, #71 orifice installed. I notice that when the temperature outside is higher, my vent temps are lower, eg. it's 80 out and vent temps are 60, when it's 100, vent temps are 55. Would it make sense to change the orifice?

Hope you don't mind my post Baz.

Hey Matt - no worries - my thread is available for anyone if it helps. I pretty much resolved my issue anyway. My tech did evacuate the old lines and flushed before recharging. Not sure about the orifice. Don't know the answer to your question but maybe Bill will chime in.

Sounds like you are pumping in some nice cool air though.

[billybek]

Originally Posted by mattdavis11

When a compressor locks up, and most scroll compressors do eventually, there would be bits of metal carried throughout the system, correct? Did the installer flush the lines and replace the orifice?

One of the nice things about scroll compressors is that they have so few moving parts compared to a reciprocating compressor. Even when a decent size recip piles up the amount of metal they send downstream can be minimal. When they burn out they will produce some nasty stuff in the system an can contaminate the system. A few years back we would flush a really bad burn in both directions using a refrigeration oil pump and R-11. Now there are more environmentally friendly things to use for that purpose.

It seems to me that it would be necessary to flush as there would be contamination of the oil, and possibly bits of debris remaining in the system if he just replaced the compressor/condenser and the in line drier.
See above. On a bad burn a high acid filter drier can be installed to help clean up the system. A suction filter drier can also be installed temporarily until the system is cleaned up. Oil samples will typically let you know when the system is clean.

Also, just the same as R12, R-22 can be purchased with a license, however, neither are no longer are allowed to be manufactured in the US. That's why the prices have skyrocketed for both. It is total BS, both refrigerant are more efficient than the successor. Can't have it both ways, but with this you get neither. Less efficient refrigerants will require more energy to meet the desired outcome. So, what is worse, an energy plant emitting loads of pollution to keep up with demand, or a few molecules emitted into the sky.

Absolutely nothing to argue with here. I agree with every word. Proper enforcement and sales to qualified mechanics/technicians would go a long way to eliminating emissions. Manufactures should be manufacturing products that encourage good refrigerant management practices. R-22 while not a perfect refrigerant environmentally is not a bad ozone depleter or the worst global warming refrigerant.

Question for the gurus. I have a 2.5 ton unit servicing about 1300 sq.ft, #71 orifice installed. I notice that when the temperature outside is higher, my vent temps are lower, eg. it's 80 out and vent temps are 60, when it's 100, vent temps are 55. Would it make sense to change the orifice?

Sounds like the condenser could use a variable speed fan controller. There are some that are not too expensive. They will allow the condenser to be the right pressure and temperature to provide consistent indoor air temperatures.
I wouldn't mess with the orifice at this point. Kind of hard to guess on this one but it sounds like the condenser is logging up with refrigerant during lower ambient temperatures.

Hope you don't mind my post Baz.

I wouldn't do an orifice change without checking charge and running conditions. Temperature at the evap coil outlet and temperature at the metering device inlet and suction and discharge pressure.

Canada has set it's sights on HFC's like R134a for phase out just like many European countries.
Goodness knows what will be next...