Electronics & Appliances Best Posts in Thread: Aircon split type

Well, the OP did write "Hope this helps. If not can someone explain please." There cannot be a much clearer view of this person understanding part of his dilemma and asking (very politely) for help if he had not explained clearly or accurately enough. We all have something 'special', be it knowledge, skill or experience and can use that to improve the lives of those around us (including members of this forum). We do not need to try to belittle other people who have less expertise in our field - this is what you did. All it needed was to state the facts as you see them and give further advice - and it really IS possible to do that in a pleasant manner (as I am doing to you now). I am sure the OP, a seemingly very nice person, would have appreciated that. You are not the only person who sometimes writes like this but why not all of us make life better for everyone else as pleasantly as we can.

 

At full load yes, but under typical operating conditions no. Running at full load for an hour, a 0,75 HP air conditioner multiplied by 750 watt/HP = 560 watts, divided by 1,000 watts/kW = 0,56 kWH

Most of the power consumed by an air conditioner goes to running the compressor. When the air conditioner is running you will sounds from two components in the air conditioner. The fan will make a typical fan noise and the compressor will make a rattling noise.

Although the fan runs all the time, the compressor of a non-inverter type cycles on and off during the operation depending on how hot the room is. This is because the typical air conditioner cannot vary the RPM speed of the compressor motor. It can only turn it on and off. An inverter type air conditioner is able to adjust the RPM speed of the compressor so this type slows down the compressor which is a little bit more efficient.

The air conditioner will consume less power during the times that the compressor is off or running at a slower RPM.

So to answer your question it depends on how hot the room is. 0,56 kWH is for full load only.

 

I haven't read (or understood) all of the technical power analysis reports, but I did see that he mentioned that it seems to be colder now. I had a similar problem with my split aircon, and it turns out that the remote control is also the way in which the main aircon unit senses the temperature (at least with my unit). Putting fresh batteries in my remote made it go back to working normally. So (at least with mine) you need to be careful of where you place the remote as that is where the temperature will be monitored (so don't put it on a table where the sun shines on it for example), and make sure to keep good batteries in it.

 

Dear @furriner, Please "Be careful on these forums because sometimes there are people who have been educated in the subject you extol so confidently about." and "... you are risking the wholesale lowering of the IQ in this thread ...".

Although he left off the H, it is obvious that the OP meant 27 kWH per day instead of kW of instantaneous load.

In the OP's original post he stated: "Just had it completely cleaned. last reading 27 kw 24 hours, ..." The "24 hours" should have given you a hint that he meant the electricity consumed over the entire 24 hour day.

In a later post, the OP attempted to clarify this by including the calculation of cost per day: "the one in question is using 27 KW a day * 10 = 270 pesos." The fact that the OP is multiplying the "27 KW a day" by the utility rate of 10 pesos per kilowatt hour (kWH) should make it obvious to you that he actually meant 27 kilowatt hours (kWH) per day instead of 27 kW of instantaneous load.

As an electrical engineer you should realize that this is the power consumed over a 24 hour period. Assuming that the air conditioner is running all day, we would take the 27 kWH divided by 24 hours per day to get 1.125 kW per hour or 1,125 watts per hour consumed. It has been hot lately so assuming the air conditioner is running at full load and not cycling down, 1,125 watts at 750 watts per HP would equate to a 1-1/2 HP unit. Which is much less than the 27,000 watts you assumed as the instantaneous load.

Furthermore, they may be looking at the meter and not considering the other appliances in the apt.

@jimeve, Does the 27 kWH include other appliances like a refrigerator? Is the tenant running it all day? Please also give us the rated power of the air conditioner unit.

It has been more humid lately. I noticed that the freezer in my refrigerator frosted up which reduced its efficiency. It was running all day and not cycling off. After defrosting it the electrical consumption dropped way off.

Thanks

 

Thanks for the feedback. This kind of explanation clarify why a split unit is more consuming friendly than a window unit. It makes sense that with an room temperature of 34 degrees Celsius you wanna reduce to 28 or 24 degrees for example, it will make a difference how much Kwh is needed during the hours the unit is running. No more questions............!

 

If you want to do this yourself (DIY), then the next step is to isolate the A/C unit and check its current draw. You should be able to do this by turning everything in the home off except for the A/C. Modern electrical meters are digital and have an instantaneous readout. There is usually two readouts. The larger display is the cumulative watts since the meter is installed. The other smaller readout will cycle through a series of numbers. Instantaneous watts or kilowatts, Amps, volts, etc.

First turn everything off and check that the meter reads 0. Then turn on the A/C and let it run for a few minutes before reading the instantaneous watts and amps. Compare these readings with what is shown on the nameplate.

If you have an analog meter things are a bit more challenging. Find a friend or hire a technician with a portable ammeter.

 

Okay. Very good.
So why did you throw out the term Rhone Power Consumption in your attach on Jimever?
I was impressed with your EE^2 degree up until now.
, Rhone stuff is fine if you're talking global warming, I don't really consider air-conditioning in that realm.

 

That was an example if you care to read what I posted about the drill. Please refrain from condescending remarks, It's not the first time. I have been a member on this form since it was formed 2006, I joined two months later in February 2007. You being a new member have to learn some manners. Keep out of my way.

 

It's my tenant who is running the aircon. the A/C is in a small bedroom but he leaves the bedroom door open so the cold enters the sala, so house is 27sqm.
Might have over used the A/C and needs re-gas. Got someone to test it today.