A little problem

[unixxx]

Well, I removed the evaporator fan from my A/C unit, shoved the temp sensor into a light bulb, and then ran it for ten minutes. I'm a little worried because I'm not seeing any frost on the evap and because the evap doesn't feel any cooler than the condersor. The compressor is on and does get warm to the touch. I have a 12,000BTU unit, I don't know if that might have anything to do with it. I hope it's not broken :( The only reason I could think it might be broken is if one of the lines ruptured before I got it. Is there any way to tell whether the lines are actually filled with refrigerant?

[unixxx]

"4. feel the top of the compressor to see if it is warm

or cool.

5. if warm the unit has lack of refergerant.

6. find the leak and repair."

Is this true? Should the compressor be warm or cold? When I ran the A/C unit the compressor just kept getting hotter until I decided to turn it off.

[DocGolem]

I'm no expert, but you need to have a fan on your condenser.

The fan is there to let the gas cool down to ambient temperatures. So you need to have a fan on the condenser and don't have a fan on your evap.

If they are the same fan, you might have to improvise and put it on the other side of the condenser.

[unixxx]

Yeah, I've got a fan on the condenser, I only removed the fan from the evap. They're actually on the same shaft so I just removed the fanblades for the evap and left on the fanblades for the condenser. I'd also like to mention that the evap felt like it had some serious static charge (or slight voltage), whenever I touched it I got a constant pin-:banana::banana::banana::banana::banana:ing feeling, I didn't get this feeling from any of the pipes, compressor, nor condenser. :confused:

[DocGolem]

That sounds like a grounding problem if you feel voltage coming through. Maybe check for a lose wire and make sure the unit is properly grounded. I don't know if that has anything to do with the temperatures not dropping though.

You might want to PM chilly1 or pc ice or post your problem in the Phase Change section. More experienced personnel will help you out there.

[Briggs]

If your evap is not getting any colder then the amb. air it probably dosn't have any ref in the system. You did say that a line was punctured didn't you?

[DocGolem]

The only reason I could think it might be broken is if one of the lines ruptured before I got it. Is there any way to tell whether the lines are actually filled with refrigerant?

This might be the case, where did you get it from? They should be able to replace it if it's from Sears or somewhere like that. Just make sure you put it back together and there's no visible damage.

[unixxx]

I'm really not sure whether a line is damaged; since I got it I haven't noticed any leaking at all and have been extremely careful. However, I assume that's the problem as it matches my description in all of the troubleshooting guides. I bought the unit on eBay luckily from a guy with great feedback. Since I haven't hacked anything it's entirely possible for me to put it all back together (not that I'd want to pay the return shipping). I'll check for lose cables and stuff to see if I can fix the grounding problem. Oddly, after touching it every 10 seconds for ten minutes straight I didn't feel any pin:banana::banana::banana::banana::banana:ing until near the end of the period.

[unixxx]

Now that I look at it I notice that the evap is touching the drip-pan and used to be insulated from it by a shroud I removed. However, I would assume that it would still be grounded anyway as it's directly connected with copper pipe to the condenser which was always grounded. I'll post my problem to the Phase Change forums and hope no one reams me out for cross posting :)

[masterofpuppets]

You don't necessarily need a condensor fan. Look at most freezers and fridges. Do you see a fan?

[unixxx]

Well, I found a rubber cap taped onto the a piece of styrofoam I ripped off one of the pipes. It doesn't seam to really go anywhere so I'm not quite sure what it's for. I also noticed that the compressor has a thermal switch on it to cut out power when it gets too hot. When I was running it the compressor never turned off, so it wouldn't have been overheating. I heard somebody else mention in the forum that their compressor got hot and then cooled down when the refrigerant started to cool. Do you think I'm just being impatient and not waiting long enough? I inspected all of the pipe brazing and couldn't visually detect any problem. I'm pretty sure the compressor doesn't have any oil problem either because the bottom of the drip-pan was dirty (bugs & crap), but not with oil, which means there wasn't any oil cleaned up. I'm also using a 12,000BTU unit, might this cause it to take longer. Should I try to run it for say 20mins, or does this run the risk of damaging the compressor?

[dward3]

unixxx,
have you tried connecting compressor to the on/off switch with thermostat disconnected or removed? Keep up the good work!

[unixxx]

No, I was going to but wasn't sure if it was a good idea to run the compressor if it might have no refrigerant in it. The compressor specs say that the condenser is supposed to be around twenty degrees warmer than the evaporator, so unless I just didn't wait long enough I think there was something up with it before I started. Any compressor expects out there feel free to elaborate :)

[Aphex_Tom_9]

yeah, run it for like 15 minutes, if nothing happens, the compressor's broken, or a line's broken. the evap should start getting really cold by at least 10 minutes. dont worry about damaging the compressor, they usually get pretty hot (about 60c is normal) and as you said, it has a thermal shutoff.
edit- the specs say it should be 20c warmer than the evap??? that makes no sense.

[dward3]

To stay on the safe side, do not run the compressor more than a few minutes without the condenser fans. ;)

[unixxx]

I ran it for around 10 minutes and noticed no change in temperature in the evaporator nor the condenser. The compressor, however, didn't get very hot, maybe only 80-90 degress Farhenheit. I still have a fan on the condenser, just not the evaporator. I'll try running it for 15 minutes and see what happens, maybe I'll let the compressor get a little warmer this time. In the mean time I'll plan start planning the safe removal of any remaining refrigerant. I'm thinking I'll need the following:

2 Needle/Saddle/Piercing Valves
Old Compressor
Propane Tank
Set of Gauges
Tubing

I know the local hardware stores have tons of needle valves in stock, but I doubt these are suitable for work with refrigerants. Where do you guys get your needle valves? Thanx

[unixxx]

Aphex_Tom_9, sorry, the datasheet said under test conditions the evap was 45 degrees F (7.2C) and the condenser should be 130 degrees F (54.4C). So that's an 85 degree F temperature change.

[Aphex_Tom_9]

oh, i see, so did you determine if it's broken?

[unixxx]

Gonna run it for 15 minutes tonight and if I don't have any luck I'm gonna follow the standard recovery procedures, replumb the setup into my enclosure, recharge, and test. If it still doesn't work I'll replace the compressor :( . First however, I need to find a gas rated piercing/needle valve. Does anyone know where I can get refrigerant fittings and supplies like this from? The locations in the sticky in the Phase Change forum appear to be only in the UK or no longer available. Thanx.

[unixxx]

Well, I ran it for twenty minutes and absolutely nothing happened other than the compressor heating up to about 90 degrees F. I guess it's safe to assume the refrigerant has leaked, but regardless, I don't want to chance releasing ozone depleters or asphixiating myself. I'm gonna do some searching for piercing valves. What kind of horsepower compressor should I use to vacuum the system and tank when "recovering" the refrigerant?

[unixxx]

I finally found a piercing valve on a site Gary recommended a while back. I'm gonna grab Part # EZ-40288 on this page http://jbind.com/Catalog/access_valves/line_piercing_access.html They don't sell directly and I've inquired via e-mail as to their distributers; hopefully the prices won't be too high. :toast:

[dward3]

unixxx,
Have you tried adjusting the temperature settings to cool mode with remote control? :)

[unixxx]

Unfortunately the unit didn't come with the remote control (gotta talk to the seller about that), but I have set it to cool mode and to 60 degrees F on the front panel. I'm pretty sure all of the electronics are fine because I can hear the compressor kick in when I turn the target temperature down below the room temperature.

[unixxx]

The guy at J/B Industries (the refrigeration supplier) replied to find out where I live (for distributers) a couple of days ago. I replied but haven't heard anything since. I'll see if I can find somewhere else.

[dward3]

unixxx,

Johnstone Supply (http://www.e-johnstonesupply.com/scripts/cgiip.exe/WService=wsbroker1/login.htm?store=Corp&browse=yes&category=9) might be a good store to check out for your Refrigeration & Air Conditioning supplies. How's your project coming along anyways? Here's another link to search them by state. Click-Here (http://www.e-johnstonesupply.com/main/selectstate.asp) :)

[unixxx]

dward3, thanx for the link. Grainger seems to have everything I need and I just setup an account with them which has to be "verified." Hopefully they won't notice that I'm not a large company. JohnStone has exactly the same part I'm looking at in the Grainger catalogue, but again, it requires registration verification. I'll try both and see if either one approves me.

[unixxx]

Well, I've got good news :toast: . The seller of my A/C unit said that he will refund me whatever amount I think is fair to cover a recharge of the system. Does anyone know what a typical recharge for a 12,000BTU R22 system would be? Thanx.

[unixxx]

Now that I've found the valves I just need to grab some refrigerant hose, a guage/manifold set, a spare compressor, and a tank to store the refrigerent. I was wondering though, do I really need a second compressor? After the refrigerant is drained can't I just install a y-valve on the high side of the compressor and have it create its own vacuum. One side of the y goes to the compressor, one side to the high line, and the y branch is used as an outlet (to the external air). Then I can install an on off valve right after the y valve. That way when I turn the y valve to the outlet and shutoff the valve right after the y valve I can put a vacuum on everything after the second valve and have the compressor push it all out of the y valve outlet. Since no one can probably tell what I'm saying I'll try to post a diagram of what I mean soon. BTW, I notice the manifolds/guages are all rated for different refirgerants. Is this really important and will R290 work with any of them? Thanx.

[unixxx]

Ok, I found an awesome guide of charging here: http://www.vr-zone.com/?i=716&s=1 Based on information from this guide it seems discharging it exactly the same except I remove gas from the high side rather than add it to the low side: http://xtremesystems.org/forums/showthread.php?t=36699&highlight=piercing Since the entire unit only cost $130 I'd say that $100 is a fair reimbursement to cover recharging it since most people say a recharge costs at least $150. Correct me if I'm wrong. As for this list:


2 Piercing Valves
Guages/Manifold
Compressor
Refrigerant
Tank


I decided that my previous idea below would leave too much air in the lines. Now I've just gotta pick the right components and do some more refrigerant research.

[unixxx]

Piercing Valves: http://www.grainger.com/Grainger/productdetail.jsp?ItemId=1611786906

Manifold: http://www.grainger.com/Grainger/productdetail.jsp?ItemId=1613507268

Refrigerant: R290 from local store

Compressor: eBay

Tank: ???

Anyone know what size of tank I'd need to hold the typical amount of R22 in a 12,000 BTU system? Thanx.

[unixxx]

Ok guys, finally placed my order with Grainger and it should be approved (I hope) within 24 hours. Just need a tank (local propane center), compressor (eBay), and torch (Home Depot). Thanx for the help so far.

[JSU]

If your compressor is not getting hot with it on for 20mins it is prolly under powered and not working correctly. Rotary compressors runin excess of 130f and can get up past 200f (ive boiled water on one). So with or without refrigerant you should have alot of heat on that compressor. Nex tthing is if there is a leak why dont you search for it before buying everything to fix it? I guess it a bit hard now seing as if there is one there will be no pressur ein the system. When you do get you piercing valve attach a gauge to it before you do anything else. If there is high pressure the problem is with the compressor. O and the condensor should be around 15 degrees from ambient so not having a fan for alittle while is ok if its not getting too hot. An the reason why frigdes and freezers (most of them that is) dont have fans on them is becuase they use static condensore which utilize a single row design wiht larger fins as apposed to a active condensor with multiple rows and smaller fins. So basiclay they are desinged to run that way. Besides the fact that they have nothing near the power of a 12000btu a/c. I think they are in the 1500btu range at most. As for recovering the refrigernat I beileve that the new propane tanks will not let you put stuff in there but even if you could ou should avoid it at all costs. It is not meant for that a somthing could rupture g-d forbid and it gets ugly. You can use a small propane torch and braze a shrader valve onto the tip (with the tank disconnected of course). The you can use it as a refrigerant. Good Luck and be safe!

[unixxx]

After around 15 minutes the compressor got almost too hot to touch. I was just going to buy everything now because even if there isn't a leak I'm planning on replumbing and recharging it on installation. So I thought the easiest way to leak test it was to buy the tools I would need later anyway and use them. Unfortunately Grainger says they need proof I'm a business so I guess I'll have to find some of that. What did you use as your recovery tank? Thanks for the charging suggestion, I was thinkinh about doing that. Right now I've just gotta work on getting the parts, Johnstone Supply never sent me an e-mail when I registered my user name online, so I couldn't browse their catalogue either. Thanx.

[unixxx]

Ok, after a short long while I've finally had a chance to breach my A/C unit's lines. Surprise! There was no refrigerant in them. I guess I'll be recharging them with R290 but first I need to find the leak. What process would you guys use to find a leak in your system? Just pressurize it and use some soap and water?

[wdrzal]

What process would you guys use to find a leak in your system? Just pressurize it and use some soap and water?

Thats the best way, A empty spray bottle with a squirt of diswashing soap & water works well. More soap isn't better only a teaspoon full. Spray all the joints and wait 5 min the leaking one will show.

[unixxx]

Is there anything wrong with using the output of my recovery unit to pressurize it or will this damage the recovery unit? Actually, with the appropriate adapter I guess I could just use an air compressor.

[wdrzal]

normaly you use nitrogen to test for leaks but if you don't have that just use the refrigerant you are going to use. jug pressure is enough to find leaks.just put in a static charge of vapor....