< 1 2 3456789 > 1 posts, read 151,253 times Originally Posted by ByteRider I have been in the industry for more than 15 years on the Gulf coast and i totally disagree. Not just anyone can replace a compressor. First how do you know it's the compressor? Second, what caused the failure? Was it a burnout? Why would I need to know if it was a burnout? What must I do if it was a burnout? Not to mention the possibility of electrocuting yourself. Next you use 15% silver solder not 50%. What are the dangers of soldering? What happens with oil residue in the refrigerant lines? What happens when flame is introduced to freon and freon residue in the lines? Ever heard of phosgene gas? What about the Oxygen Depletion Potential of freon? What about how inhaling freon causes heart arrhythmia? What about refrigerant recovery and disposal? What about evacuating the system? A/C systems, are very susceptible to moisture and other non condensibles. How are you going to purchase replacement freon with no EPA certification?

What about the life threatening dangers of freon? How much freon do you add? You just can't go by the factory charge on the nameplate. You have to take into account many factors and then calculate your super heat and subcooling in order to achieve a proper charge. There are so many things to consider before trying to tackle something like this. If injury or death doesn't deter you, then the fact that you did it yourself will probably void any warranty that come with your $1000 compressor should. I can look up how to do an appendectomy online and get step by step instructions but I'm pretty sure most people would agree to just get someone who has been properly schooled and trained to do it. This is not like changing a fuse or the oil in your car. You could die or even possibly kill someone else many different ways if you don't know what you are doing and I would never recommend a compressor change out as a DIY project for a novice. 16,739 posts, read 46,615,361 times 1 posts, read 151,139 times

9,224 posts, read 34,826,474 timescost of 5 ton ac system Originally Posted by archcolinheat ac combo unit By yesterday's standards, a 2ton unit would probably be OK. ac and heating units reviewsBy today's standards there no telling without a physical inspection of the home. Calculating a house for A/C requires a Manual-J worksheet. There are a lot of factors that are used in the calculation- # of doors and windows. Wall construction and insulation. compass direction (solar gain), etc. Then there's the Manual-D for the duct system. and finish all your calculations with a Manual-S. Today, there is no reason to guesstimate. By doing a thorough calculation you will have a system that works at peak performance with minimal operating expense.

2,398 posts, read 4,448,953 times Actually a license is only required if your system uses R22 freon, which of course most old systems do. If you have or are replacing with system with a R410-A refrigerant, no license is required. So long as your not touching a R22 system, your fine. If your replacing a R22 system with a R410-A system you need a licensed HVAC contractor to recover the R22 refrigerant from the old system before removing it. Originally Posted by ComfortZone1971 If you haven't mastered the mysteries of the circuit broker or equipment disconnect, you probably shouldn't be doing anything yourself. Pretty much anything you touch now a days voids the warranty. I wouldn't mass with the R22, but I wouldn't let a little thing like voiding the warranty stop me from working on it. Originally Posted by TechGromit I know the EPA would love to talk to you! You are required to have an EPA Section 608 Type II or Universal certification license to handle R-410A but no license is legally necessary for purchase.

"to handle"- means working on systems that support R-410a refrigerant. Originally Posted by K'ledgeBldr I stand corrected, I assumed since no license is required to purchase it, no license is required to install it. 1 posts, read 147,284 times 1 posts, read 144,056 times DEaler not compling with warranty 342 posts, read 1,022,362 times Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.Condensing Units and Condensers Daikin offers condensing units, air cooled condensers and fluid coolers to meet a variety of project requirements. Whether the priority is life cycle costs, initial costs or quiet, reliable performance, we have a solution. Units are available from 6 to 212 tons with a full range of options to meet efficiency, performance or serviceability requirements. 6 to 140 tons

Condensers - Air Cooled 130 to 2,225 MBh 5 to 212 tons Find Sales, Service or Parts Water Source Heat Pumps I'm planning to install a 5 ton central AC. I'm deciding between a condensing unit that runs on 220V and a costlier unit that runs on 207Y three-phase. My understanding is that three-phase motors use less power, and that this is their primary advantage. But no one seems to be able to tell me how much less power. Without knowing that, it's hard for me to make a decision. I'm sure the answer is some form of "it depends," but can anyone give me a ballpark? Should I figure 10% less power consumption, or more like 50% less. Any guidance is greatly appreciated. Also, the wikipedia article on three-phase power claims that three-phase motors vibrate less. Is this something I should care about? Will a three-phase motor therefore last longer than a single phase motor? electrical hvac air-conditioning energy-efficiency electric-motor If you have the condensers already selected, you should be able to get the two pieces of data you need to make a decision.

1) price increase for 3 phase condenser 2) operating power for single phase and 3 phase units. I suspect they will quote you that the two units consume the same amount of operating power. Yes, theory says 3 phase motors run smoother just like V8s run smoother than 4 cylinder engines. But the practical difference in motor life is something you will probably never see. One possible reason that a 5 ton unit is available in 3 phase is that the amperage is lower and thus you could save some money on the wiring cost. This comes at the cost of an extra circuit breaker. Think I'll chime in here and add my two cents to these other good answers. There are two components to the original question: How much less power does will the 3 phase A/C compressor unit use? Longevity of three-phase motor versus single phase Motor Efficiency = Power Output / Power Input It takes a certain amount of power to run the compressor regardless of single or three phase power... this is the power output.

The power input is what you are trying to minimize, thus you want to increase efficiency as much as possible. The trouble is this metric (efficiency) is a hidden combination the components inside the compressor unit (compressor, fans). It is not necessarily true (but it usually is true) that three phase is more efficient than single phase. I would look at the SEER rating which 'automatically' includes the motor efficiency for a better indicator of "cost to cool". Three-phase motors and compressors are generally more reliable than their single-phase couterparts. But like anything else, there is more to it than that one attribute. Using Philps' automotive engine example, a 4 cylinder Honda might be more reliable that that old smallblock V8. Certainly less in the three-phase motor. And generally less vibration equals greater reliability. Three-phase motors have lots of starting torque and don't (typically) require any special circuitry to start (capacitors, centrifugal switches).

And of course fewer components means fewer things to go wrong. Is disappointing that the three-phase equipment is more expensive. Almost always, three-phase motors are actually cheaper than an equivalent single-phase motor. 1hp = 756 watts 5hp = 3730 watts 3730 watts at 230 volts = 17 amps 3730 watts = 3730(watts) / (207(v) x 1.73) or 3730 / 358.11 = 10.4 amps. Three phase is 40% less amperage. There are other things to make this accurate, like motor efficiency and power factor. I used 1 for each. Another savings is that with the reduced amperage you can reduce your conductor size for your feeder. With the price of copper today that could help matters too. I used 5hp for no special reason, just a nice round number. I suggest using three phase. The above example of 5hp at 240v = 3730 watts and 5hp at 207v three phase = 3730 watts is correct. You draw less amperage with three phase but with more added voltage. Power is power and you draw 3730 watts with either scenario.

Your savings will come in the durability and longer life of a 3 phase motor. You will also reduce your feed supply conductor size but will have to add another pole to your breaker or disconnect switch and one more conductor too! By using a three phase motor you will also balance your load on your service and probably increase your power factor efficiency which your hydro utility probably charges you extra based on a lower one, (check your bill). The nod goes to three phase but only slightly. Pay hundreds more for a 3 phase not thousands. I have a 220 volt device (motor, dryer whatever... it makes little difference for this example). Single phase device draws 43 amps (43 x 220 = ~ 9460 Watts or 9.5 KW) Same unit with 3 phase draws 25 amps (25 x 220 =~ 5500 Watts or 5.5 KW) *** The same amount of work is output with either unit despite the 3 phase using less power because it is more efficient. I currently pay $0.14 / KW and Run the unit 6 hours a day. Single phase costs me (9.5 x .14 x 6) per day to operate or ($6.65).

Three phase costs me (5.5 x .14 x 6) per day to operate or ($4.62) a difference of $2.03/day. Therefore the difference in 1 year (5 days a week) is a yearly savings of $527.80. 208/120Y is cheaper for supplying condominiums because one neutral can carry the unbalanced loads of three ungrounded conductors. But for the consumer, the voltages difference of 208V vs 240V usually equates to the same overall wattage, with the only negligible concern being it takes longer for heating elements to reach their desired temperature. As for motors, whether or not they're more efficient is not a question, but rather if you'd notice that difference in your monthly power bill. That I would probably say no just because being a residential area. AS WE KNOW 1 TR = 3.516 KW FOR 5TR IT IS= 3.516X5 CURRENT FOR 430 V SUPPLY = 17.58X1000/(1.73*430*0.9) ASSUMING pf 0.9 Sign up or log in Sign up using Google Sign up using Email and Password Post as a guest By posting your answer, you agree to the privacy policy and terms of service.