[LEFT]I've seen some extremely helpful responses from the threads I've read, but haven't come across a situation similar enough to mine to help me solve the issue without calling a certified hvac tech. I knew nothing about hvac system up until a few weeks ago, but am technically inclined and have educated myself and hope to be able to resolve this problem before the tech I've scheduled comes out in 2 days. This next part isn't exactly related to fixing my issue, but explains how it happened and I'd also like to know if there is grounds for any legal action that I could take, but you may skip this part if you want.[/LEFT] Here is what happened. Our neighbors toddler (who is great friends with the condenser units, likes to hug them etc.) turned my condensation drain pump pipe completely vertical...unbeknownst to me. The a/c stopped working (condenser and central blower). I have cameras setup around my property, none directly on the unit, but enough to be able to tell that no one was on our property except for the people that live here (everyone has some type of fencing, retaining wall, wooded area with barbwire, etc. so trespassers do not happen anyways). We are the 2nd to last house on a dead end and they are the last house with our condenser on the far side of our home directly next to theirs. I brought this up with our neighbor and she failed to take ownership for her child's actions so I am left trying to fix this mess as cheaply as possible. If anyone knows if I have anyway to pursue them for the damages and inconvenience I'd appreciate the advice as they are the worst, most passive aggressive neighbors and I have bent over backwards to help them many many times both financially and physically (cared for their entire household when they had the flu, made them food, changed diapers, that kind of bent over backwards!) But I digress.... [B]TL;DR[/B] Condensation drain pipe backed up over 5gal water into the overflow pan in the attic causing the safety switch to cut the central unit and condenser off. There was insulation in part of the overflow pan which absorbed water that then ran through the ceiling causing visible water damage. I shopvac'd the water out and everything came back on. I thought that was the end of it. About a week later the central blower and the condenser go off again. I took to the internet trying to diagnose the problem with my multi-meter and trial and error. After many many hours I was able to find that the 240v to 24v 40VA transformer had burned up. The in-line 5amp fuse on the secondary/low-voltage side had not blown nor had the 3amp fuse on the Aprilaire model 6303 control board. I sourced a replacement transformer and hooked it up and everything worked...phew! About a week later this transformer burns out as well! This was about the same amount of time from when the overflow happened to when the first transformer blew. Coincidence?? At this point there is obviously something else wrong besides a bad transformer (I knew this was likely the case before hand, but just hoped the overflow caused it to burn up for some reason or another). So I installed a third transformer, but this time I installed a 3amp breaker in-line the secondary/low-voltage side (even though it had a 5amp in-line fuse and then a 3amp circuit board fuse, but I didn't want to burn another transformer as they really stink the house up!) Within a minute this 3amp fuse tripped...great! I did a lot more research and tested nearly everything and have been unable to narrow down the problem. The only thing I have not done is unhook every single 24v wire from every contact point and test for continuity between each and every one, that is my last resort. This post is my 2nd to last resort! Upon the suggestion of a post I read I unhooked the ground from the secondary side and viola, the blower and the condenser now come...but there is a catch! The condenser now runs 24/7 and the only way to shut it off is flipping its breaker. The thermostats will not turn the condenser off. . [B]I'm going to post a list of the symptoms/things I have tried and noticed and hopefully someone more knowledgeable will be able to guide me in the right direction. .[/B] [LIST] [*]If the a/c is turned on the in-line breaker on the secondary side trips either instantly or within a minute or 2 tops. [*]If the a/c is on and the ground is unhooked and I attempt to ground while it's cooling I get a large spark and the breaker is tripped. This does not happen if I leave one of the secondary wires unhooked and attempt to connect it while the unit is running, no sparks or anything. (I read that doing the latter and getting a spark indicates that there is a short) [/LIST].[LEFT][B]The rest of these facts are with the secondary ground unhooked[/B][/LEFT] . [LIST] [*]With the secondary ground unhooked the condenser never shuts off. [*]The thermostats, when set to auto and cooling will not turn the blower off even once they reach temperature. [*]I have 2 zones, if either/both reach temp they continue to run. [*]If zone 2 is off, and zone 1 is cooling, if you manually turn zone 1 off, zone 2 will start blowing even though the thermostat is off. This happens vice versa as well. Basically if the thermostats are at any point set to cooling you cannot ever turn the blower off and the condenser is always running still. [*]Now if you set the thermostats to run the fan only then they can be controlled individually and the blower will turn off and on as instructed. This is with the condenser still running non-stop. [*]If the breaker for the condenser in the main breaker box is turned off, the condenser stops, but starts running as soon as the breaker is turned back on, even with both thermostats completely off. However, if the breaker on the central unit in the attic is turned off and back on the condenser will not come back on until a thermostat calls for cooling. [/LIST].[LEFT][B]Some voltage and contactor facts[/B] .[/LEFT] [LIST] [*]The transformer is getting 240v to the primary side. [*]The transformer is getting ~26v to each of the secondary wires. If the one 24v wire ground is attached it reads 0v. [*]When running the contactor is getting 240v to the bottom connectors and 240v to the top [*]The right side terminals are getting ~25V and the left side getting 0v. The right side has 2 connectors, one runs into the condenser and the other runs to the circuit board connector labeled T1. The left side runs to the same connector directly beside the T1 slot and it is labeled C . [*]The contactor is not stuck and appears to be functioning properly. [*]All 3 connectors on the capacitor are reading ~120v [/LIST]. Aside from disconnecting the whole lot of low voltage wires from all of their locations and testing for shorts is there anything else I can do? And is this likely related to the condensation pump backing up or is this a more likely to be a very uncanny coincidence that this begins happened at this time? If it is not a coincidence how would the overflowed water affected/be causing this issue? I look forward to someone with knowledge or field experiences relevant to a situation like this that can help me resolve this issue on my own. Not only will you help me save a great deal of money, but I will walk away with the quite the education in hvac systems, something I literally knew nothing about besides how to push the arrows on the thermostat a month ago lol! Thank you guys in advance, I've seen some wonderful responses to other people's questions and I hope mine wasn't too long winded for you!

Ruud (UAPM-030-JEZ) EMC Condenser Fan Motor conversion to PSC Here is what lead to the conversion, skip ahead to see how it was done. A tenant called Saturday afternoon saying no heat on a June day in Austin, Tx. The HVAC Dealer I bought it from said this eight year old system was under warranty but it would take “five business days” (one week) to get in the replacement EMC motor and it might not be available. They made me promise, before they would order it, that I would pay them $50 for shipping and $400 labor to install the motor. Seven days in the Tx heat is an eternity so I needed another solution. I contacted a HVAC guy on Craigslist, a guy that works for himself. He took out the EMC motor and put in a PSC motor. Parts and labor cost me $250. The tech said the motor was $127 and the relay was $14, the capacitor was around $15. Compare $250 for a working system to the $450 (labor and shipping) that the Dealer wanted just to install a warranty motor that might not be available. The tech bought a PSC manufacturer’s motor from a HVAC supply store (see photo), it will mount without modification in my system. This motor matched closely the RPMs of the defective ECM motor. It also came with a white connector that can be easily reverse the direction of the motor. The amps were almost double the EMC motor and the Horse Power was 1/4 compared to 1/5 for the EMC motor. But I am trading off the efficiency of the EMC motor for the reliability of the PSC motor. He also bought a 5 MFD 370 V capacitor that the motor calls for and is written on the motor box. He also bought a C130A single pole relay (photo). After I took some pictures he pulled the old motor out, The points of contact for the four wires from the old EMC motor will no longer be used, the new motor does not use the old motor points of contact. He mounted the new motor and ran the wires. The motor came with a wiring diagram (picture). He used the middle diagram (4). Why? I am not sure why he chose diagram 4 over diagram 3. The diagram shows the White and Black wires coming from the motor going to 240 VAC (on one side of the new relay), and the Brown and Brown/White wires coming off the motor going to the new 5 MFD capacitor. The ground is self explanatory. The third diagram (photo) shows how you can reverse the direction of the motor with a connector. He mounted the new relay to the outside of the Circuit Board enclosure (no room inside) and connected the motor’s White and Black wires to one side of the relay. He connected the motor’s Brown and Brown/White wires to the new capacitor and mounted the capacitor inside the Circuit Board enclosure. Then he added two new wires that go from the other side of the new relay to “Line In” (240 VAC). The best place to tap into 240 VAC was from the lug screws on the Printed Circuit Board labeled “Line In”. Now we have a path for 240 VAC to get to the new motor. Next he added a new wire to the relay coil to ground, it goes anywhere on frame ground. The other side of the Relay coil goes to the 24 vac line coming from the furnace that demands cold air, Y1 (pretty sure). You may watch a volt meter to see the 24 vac drop out with the cycling of the thermostat to make sure you have the correct wire. The tech just took off the wire nut and added the wire from the Relay coil. We tested and it worked fine. I noticed the coil fan motor comes on first, then the compressor kicks in a few minutes later. Previously, the compressor kicked in first and a few minutes later the coil fan motor kicked in. Obviously an electrical saving feature which I now forfeit. I understand there is a ICM 251B relay control that we might add in the future. The best part is the tenant is not complaining about no AC.