| Author | Message | ||
     Thumper74 |
AC work is not my strong suit.. I have a Ranger that has a broken AC. It's charged, but I have 35 psi on both sides. I can't get the compressor to cycle unless I apply 12v to the clutch circuit. If I jumper the wires from the battery to the compressor, it will cycle, but the pressures are equalized on the high and low sides. It's safe to say the compressor is toast if there's no pressure increase, right? | ||
| Bandm |
35 psi is empty, if you recover the system you will get a couple ounces. 30 psi is about where the low pressure switch shuts the compressor off. Evacuate the system and charge by weight, not pressure. | ||
| Thumper74 |
Makes sense. Even with the refrigerant hooked up and the compressor cycling (12v), it won't take any refrigerant. Still indicative of a compressor not pumping/ | ||
| Fast1075 |
Be sure to replace the orifice tube and the accumulator when you replace the compressor. A system flush is a good idea because if you fragged the compressor, all the failure bits are in the condenser and high side lines. I also strongly suggest you have the evaporator leak checked before you spend big bucks on the rest of the job, or you can be wasting your time, money and effort. I hate R-134a and PAG "oil". Be careful with the "oil", it is toxic, and will chemically burn your skin if you get it anywhere delicate. Good luck. | ||
| Thumper74 |
I've got the compressor, accumulator, orifice, flush kit and o-ring kit. It holds vacuum fine. | ||
| Teeps |
If there is metallic contamination in the system. Flushing may not get it all out. I'm speaking from experience with Honda AC systems. The condenser and evaporators are similar in construction to engine coolant radiators. And, they are very fragile when it comes to mechanical cleaning (roding) a disassembled core. | ||
| Fast1075 |
Have a go at it! (speaking from 31+ years in the HVAC field). | ||
| Kenm123t |
Lol Harry ever change the EXV on 30hxc series Carrier chiller? then change the oil ect after the tube repair? I have salvaged several flooded one s Gallons of Sw220 nasty stuff. The 6n screws use a 1125 oil filter Its actually from a F/A 18 hydraulic system filter. | ||
| Fast1075 |
Ken, we stay away from those. All we have are a few 30RAP units. Nice and simple. We do a crap-ton of small refrigeration. Lets just say I buy Cap Tube in the economy 100 foot rolls. I'll never forget the WTF moment the first time I was what happens to PAG when the condenser coil gets plugged up with McDust. I sent samples to the Tecumseh engineers that didn't believe me. (for the curious, but uninformed, the "oil" turns to "rubber" and chokes up the works). Stuff sucks. I still like my old school mineral oil and my refrigerant with extra chlorine. Oh, and Thumper, if you don't have corrosion in the condenser (from running contaminated with moisture) AKA "Black Death" you will be good to go. The only thing I will add, is toss in some UV dye while you have it apart to make future leak tests easy and fun. | ||
| Kenm123t |
I m getting 2 30 RAP 25 ton redundant chillers with storage tanks and redundant internal pumps Aug 15. Doing a surgery center Plug fans boilers full automation operation and supervisory Ill post some pics You will love this Copper Ductwork ! 2700 sqft and the system costs 515k with electrical extra contract | ||
| Fast1075 |
Sweet! Antimicrobial ductwork. Now all you need is a Ductz franchise. We own Ductz #16. We do Publix, Cutrale citrus, and some for Coca Cola (when they get off their wallet). Back to the Ranger. Weigh the refrigerant charge in to get it correct. | ||
| Azxb9r |
If pressure is equal on both sides with the compressor running the comp is bad. When you remove the orifice if it is full of debris, you will need to replace the condenser as you will not be able to flush all the crap out of it, and that will cause the new comp to fail. | ||
| Thumper74 |
Argh. Ok, sucked AC down for 1.5 hours. Could not get vacuum. It showed about 4psi from start to finish. Pressure side showed 0psi. Thinking the gauge may be stuck, I charged the system. Tried to anyway. It took a pound of freon without cycling the compressor. If I jumped the low pressure switch it would cycle and stay running. After that pound of freon, the pressure was 4psi on the low side. 0 psi on the high side unless I tricked the compressor to cycle and it would build pressure, but as soon as it stopped cycling, the pressure dropped quickly. i used UV dye/oil and there aren't any obvious leaks. i took the evap case out of the truck to get access to the oxygen sensor, which was a nightmare. I looked at the evap core and didn't see any signs of a leak, not do I see any wet spots indicating an condensor leak. | ||
| Kenm123t |
Harry u up for a service call ? Sounds like you have gauge and or manifold issue what kind of vacuum pump do you have? | ||
| Thumper74 |
It's a Bluepoint electric vacuum pump. Definitely making vacuum. | ||
| Kenm123t |
Well if you didn't get a vacuum you have a leak some where. Do you have access to a nitrogen regulator and nitrogen? Pressure up to 100 psi and get out the soap bubbles and wet down every thing till you find the leak. System pressure has to be higher than 55 psi to start the compressor check the value on the pressure switch. After you repair your leak evac the nitrogen bring it back up to 0 and evac again do it 3 times that way and you will have all the water out. Think of the Ni as a sponge and vacuum will boil water but it will not move it dry Ni will grab the water and it will be removed with the Ni weigh in the charge and you should operational | ||
| Hughlysses |
Somewhat OT... Harry and Ken- nice to see some guys with chiller experience posting on here. I just wanted to pass along this "WTF" a contractor working for us encountered. Contractor was sent to an Army Reserve Center in Louisiana to assess the HVAC system, get it running, and install DDC controls. They immediately find a ~60 ton Trane chiller not running; building occupants say, "oh it crapped out a month or so ago". They go out and look and there is a 110V extension cord run from inside the building out to the chiller and into the control panel. They eventually figure out the extension cord has been pigtailed into the controls so that every safety and control on the chiller has been bypassed (!). All compressors and fans would run 24/7 regardless of demand, but it's not running at all. Next they find that one of the 4 (?) Trane scroll compressors has been replaced by a Carrier reciprocating compressor (!) and that compressor is toasted. They do a pressure test on the refrigerant side and can't build any pressure, so they fill with water. Condenser sprays like a fountain at ~15 PSI. I believe the chiller was less than 10 years old. After seeing the extent of repairs required, we junked it and installed a new one. The crap they do at reserve centers....  | ||
| Kenm123t |
Well a 60 Trane Air cooled chiller is the Brands mart window unit of the Chiller world Those things are the cheapest built POS on the market. I have tired of the Trane attitude and build quality. We use Carrier chillers mostly And more Daikin Mc Quay Ahus We Love Daikin VRF systems Carrier Aero outdoor ahus are a major pain leaks in gaskets and the drain system from hell! Avoid FHP Bosch wshps they sold non fuctional units to one of my customers and submitted on a hot gas reheat 30 ton unit with a high outdoor air percentage. They couldn't make it work. So they sent a straight cool hot gas unit but info and wiring diagram was for a heat pump! They sent a shipping form with the freight company that the unit was cooling only! Deliberate fraud. Trial starts in the fall | ||
| Thumper74 |
I decided to pressurize the system and see if I could find a leak that way, but whatever leak it was, acted like it was pretty big. I removed the evaporator core and found some corrosion, but pressurized it in some water to look for leaks and didn't see any. I DID tilt the radiator back and checked out the condensor, I found a wet, oily spot. | ||
| Hughlysses |
It does seem like Trane has gone downhill. | ||
| Thumper74 |
Seems as though this post may have derailed... Get it? Trane joke. | ||
| Kenm123t |
Well bring that Ranger over after church on sunday and I ll get you fixed up ! | ||
| Thumper74 |
I've got it out and ordered another one from Oreilly's... |
