CPS 5-2-1 CSRU1 Compressor Saver for 1 to 3 Ton Units

This thing is truly nothing short of a miracle. We have a mini-split heat pump installed in a guest house and had been receiving complaints from the neighbor that the thing sounded like a wounded yak every time it started up. It was making an ungodly loud buzzing sound, BRRRRAAAAAAAANNNNNNZZZZZZ for about 15 seconds, then would give up and try again a minute or so later. it would do this 5 or 6 times before finally kicking in and even then, would sound sort of anemic. We had a tech out (from a company with hundreds of 5-star Yelp reviews), and they said that the refrigerant levels were OK, the capacitors were OK -- it was just old and in need of replacement. I did a little research and decided to try a hard-start kit before ponying up for a new AC and I'm so glad I did. I had to do a little reading to make sure I understood where the 5-2-1 Compressor Saver was supposed to be installed and discovered that I needed to splice a couple of wires to make it work, since I didn't have enough free posts on the top of the existing run capacitor, but even so, installation took only 10 minutes and the problem was solved! The AC now engages instantly and runs silently. I love it so much, I'm getting another for an LG ArtCool I have installed at another location. The 120 AC shares a circuit with outdoor lights and dims them every time the compressor kicks in; the literature that came with this unit says it will solve this problem too, so I'm anxious to give it a shot. Great product, 1/4 the cost of a service call, and easy to install and use. Shipping was fast and free with Prime. Seriously, this thing works so well and with so little effort, I have a hard time believing it! I keep asking the neighbor if all is well and looking for clouds of smoke on the roof, but after several days of very hot weather, it looks like a winner.

My a/c unit is getting old. The compressor is weak and beginning to drag on start-up, drawing more amps than the breakers can handle. All last year, house lights would dim when the compressor kicked on and by the end of summer last year the circuit breakers began to trip at start-up. I called my HVAC guy and he came out and put on a small 2 wire hard start kit which cost $100 for the kit and $75 dollars for installation. It got my a/c working again , but by mid winter my heat pump quit working and we were forced to heat the house with the back-up electric heat strips in the furnace. Needless to say our electric bill was twice what it would have been had the compressor worked for the heat pump but we were in the middle of winter and there was no way we could afford a new system. This year I called around to get estimates on a new a/c unit and after recovering from the shock of what it was going to cost, I decided to try one more attempt to get my compressor starting again. I pulled off the $175 hard start kit only to discover it was burned to a crisp. When I installed the new 521 hard start kit, my compressor fired right up... no lights dimmed ... no breakers tripped, and it's been running perfect for almost three months now. This is a great product, very heavy duty with great build quality and cost a fraction of what I paid a "Professional" last year. I ordered it from Amazon and installed it myself. Installation was super easy. Instructions were good, but for additional reassurance, I watched a couple of videos. A/c compressors don't last forever and eventually they will have to be replaced. If your unit hasn't locked up yet , these 521's may be a life-saver and buy you some time. They could maybe even fix the problem all together until it becomes someone else's problem further down the road. WELL worth the money and I will buy again if needed.

Works great on my trane x12. It literally saved me at least $10,000. Hvac servicemen told me to replace the locked compressor with a new unit. Due too having to use a new type freon because of global warming it would have to be a new furnace also. So they tell you you can't fix it and you must spend 10k to replace it. Well fortunately with advice from a family member, a little you tube research and amazon this fixed the compressor start up. 5 minutes to plug in and mount. Took away hvac industry scam license to steal for now.

Easy to install. I have 2 AC units. I went ahead and replaced the fan/comoressor capacitor at the same time I installed this kit. My AC units are over 16 years old. I hope this kit helps the compressor last longer, because if the compressor dies, I will likely pay to replace the entire AC system.

Nicely wired with simple diagram included for installation help. It physically fit perfectly in our Carrier a/c -- right where Carrier had 3 unused mounting screws installed -- 2 for the capacitor retaining strap (that I supplied), and one for the relay. Carrier clearly cheaped out by choosing to stop supplying this component pair -- cheap S.O.B's.

I purchased my home in February with a home inspection. The home has a 3 ton Eco Temp(cheap Carrier?) outdoor unit and a no brand indoor unit(told Carrier by service tech). About three months ago my blower motor failed on the air handler in my garage. To save me money on the parts and labor, I signed up for a 1 year "maintenance contract" with a local AC service company that was recommended to me. They said it looked like my system was working fine at the time, after blower replacement of course. At my first maintenance visit, all of a sudden now my compressor is pulling 84 amps at startup and is rated for 88 RLA. They recommended a hard start kit for $200. I was also told that if this wasn't done, the compressor would soon fail and a complete condensing unit would have to be replaced as mine uses R-22. I asked exactly what that was and all he could tell me that it was a two wire capacitor kit. I am a master auto tech and decided that I could save myself some $$ and did some research. I found that two wire kits are not as reliable as the more complicated(not really) three wire kit. As I consider myself pretty handy(but very lazy), I decided to purchase this kit due to great reviews and seemingly better design. I also purchased a used amp meter off ebay to verify the readings myself. I have many meters at work but none are designed for this amperage. I found a reading of 78 amps at startup of compressor. I installed kit in about 10 minutes and now my amperage does not peak above the running amperage of the motor, 11.5 amps. I think that if I had a meter that had a faster read time or an oscilloscope, I might see a higher amperage reading. The point, as I understand it, is that the amperage spike is for a much shorter amount of time. So far this works great, saved myself money overall, and I think I got a better product than the AC company would have sold me.

I installed this in a 2002 2.5 ton Trane heat pump that had not been exhibiting starting issues. At this age, I don't expect the heat pump to last much longer, but for the price it was cheap attempt to try prolong it's life. Install was reasonably straightforward. My contactor had been replaced previously, and the new one was installed upside-down. Even if it was installed per the wiring diagram on the unit, the compressor common would have been on T2 instead of T1 like the instructions call for. There was an envelope of documents attached to the box that had the wiring diagram; as always before doing any work I compared the diagram to what was actually in the unit, finding and tracing the compressor wires to determine the appropriate places to connect the 5-2-1. My only other installation complaint was that the screws provided were a little long (certainly longer than the stock screws holding the other components in my unit). My unit had holes pre-drilled and taped over, but I was concerned that if I used them the extra screw length would interfere with the coils. No huge deal here either, there was room at the very top of the wiring compartment to drill a couple new holes that were safely above the coils. Before installing the 5-2-1 kit I measured the inrush current on the compressor common wire, and got a value of 33.6A. I repeated the test after installing the kit and got 25.9A. In more subjective measures, the compressor startup time and sounds seem to be reduced; it just clicks on to the steady hum right away now, instead of seeming to take maybe a half-second to come up to speed. Overall, I would definitely recommend this kit (or the others from 5-2-1 as appropriate for your unit size). Just make sure to trace wires and compare with the diagram, instead of blindly following the instructions from the kit. I don't knock 5-2-1 for this; they're doing their best to support decades of equipment from a wide variety of manufacturers, and there's always going to be an oddball. Same with the provided screws; they'll probably work without issue for most people. Just use your head during installation, and check for clearance behind the mounting locations before doing any screwing or drilling.

Worked as advertised and am very happy with it. Starts now are quieter and smoother. I was able to install it myself as well, after watching several YT videos. Just be sure ALL power is off at the external power box and main panel, before you mess with anything inside the AC unit of course.