In our first Iloilo apartment we had a regular window-type air conditioner in each bedroom. In our next (and last) apartment we had modern Panasonic split type air conditioning throughout. That convinced us that we wanted the split type units. Split air con units have the compressor outside in a separate unit. This is connected to the unobtrusive interior unit which contains the evaporator, fan and controls.
A significant advantage to conventional window or through-the-wall units is that they may be relatively easily removed for a thorough inspection, cleaning, power washing and maintenance. Split units generally must be cleaned in place. That can be messy. Think of your unit being power washed inside your bedroom! The pan catches most of the spray which is routed outside by means of a hose. We have had good luck with the crews sent by Samsung to maintain our split units. They have been careful. Still, easy repair and maintenance is a plus for through the wall units.
When you buy a split air con unit you’ll have to decide between the more expensive, more efficient inverter units and the regular units. Regular units have a compressor which turns on and off as needed to cool the room. Inverter units have a compressor which runs more continuously, but can vary its speed and power consumption to maintain room temperature. Under ideal circumstances, the inverter units are more efficient. If you buy an inverter unit, make sure it has adequate or excess capacity for the space. The inverter unit can silently and efficiently reduce its speed and continue the dehumidification function. For example the Panasonic CS-PS12KKQ specifications claim that the unit can adjust its output from 14,400 kJ/hr to 3,060 kJ/hr and its electrical consumption from 175 to 1180 watts. The nominal rating is 820 watts.
Inverter pioneer Daikin has a good description of the advantages of inverter units Japanese Daikin are considered the Cadillac of air conditioners.
If you buy a standard unit, it’s better for it to be somewhat undersized so that the compressor can run more or less continuously. Motors use two or three times as much power starting up as they do running. Standard units are more efficient that way (possibly more efficient than an inverter unit) and they keep dehumidifying. The worst thing is a too big standard unit which cools the room off but does not run enough to dehumidify the air. You end up with cold, clammy air. Don’t let air con salespersons talk you into a too big conventional unit. Do your own calculations and take into account just how cool you want your room to be. Conversely, don’t buy a too small inverter unit. Running continuously at peak output, they may be less efficient than a cheaper conventional unit.
Air conditioner efficiency is roughly rated through EER – the energy efficiency rating. EER is calculated by dividing the cooling capacity in kJ /hr by the power used in watts. Keep in mind that the lower power consumption of the inverter units can be accompanied by lower absolute cooling power. For example, a conventional 1.5 HP Panasonic has a cooling power of 12,740 kJ/hr whereas an inverter unit has quite a bit less capacity at 11,020 kJ/hr. This means that not only are the inverter units more expensive, but you may have to buy the next bigger inverter unit to get the same cooling capacity as the smaller but more powerful conventional unit. No wonder the manufacturers spend so much time touting their inverter units.
We decided to buy a inverter unit for our “master’s” bedroom and a conventional unit for our guest room. No air conditioning is be installed for the rest of the house now. We used an online calculator to determine the size of the unit we needed. Here’s a good general discussion of sizing air conditioning units: http://www.homeenergy.org/archive/hem.dis.anl.gov/eehem/95/950509.html
This calculator concluded we needed a 3.5KW unit for our 25 square meter bedroom. Since 1KW equals 3,412 BTU, we needed a 11,942 BTU unit. Since Philippine air con units are rated in kilo Joules per hour and since 1 BTU = 1.055 kilo Joules, we needed a 12,600 kJ/hr unit.
TIP Air conditioner sales persons are notorious for selling higher capacity units than the customer really needs. They get to sell a bigger unit but more importantly, they’ll never have a customer come back and complaining about not being cool enough.
Initially, we intended to buy Panasonic units, however when we checked the specification for a Panasonic 1.5HP inverter unit we saw that it was rated at 11,630 kJ/hr. Shopping around we saw that the 1.5 HP Samsung inverter unit was rated at 13,650 kJ/hr, substantially more than the Panasonic unit. In addition, the Samsung was about P3,000 cheaper. Since we have had very good luck with our Samsung washer, we decided to go with the Samsung. We bought two units for a package deal, the 1.5 HP inverter for our bedroom and a standard 1 HP split unit for the guest bedroom.
The purchase price included free installation by the Iloilo Samsung service center (033-508-3810 mobile: 0917-323-4818) and free cleaning and maintenance for the first year or more.
Installation crew foreman Dante F. Montalban arrived with his crew. I am very fussy about work on our house so I watched them like a hawk. I was very pleasantly surprised at how careful and competent they were. They arrived in a truck with the tools and materials they needed. It took the better part of a day for the three man crew to install the two units. The 1 1/2HP inverter unit was made in Thailand, which seems to be an Asian hub for the manufacture of refrigeration equipment. The 1 HP conventional unit was made in China. The Chinese-made unit seemed very well designed and built. The outdoor compressor/fan cabinet is made of plastic, nicely done. This can be an advantage because steel cabinets rust, especially if you’re anywhere near the ocean. I asked about repair experiences and he said he had had to replace circuit boards on the inverter units because lizards make nests and short-out the circuits. He said this is not a problem with conventional units. Generally there is more complexity and more to go wrong with inverter units.
The outdoor part of the split air con can rest on a concrete pad on the ground or can be bolted to a bracket bolted to the outside of the house. We had our welders make the brackets while they were building our house, using scrap angle bar. The brackets are attached to the wall using lead expansion anchors and lag screws.
I installed the electrical circuits and wiring. Each unit has its own 20amp circuit and breaker. Wiring is 12AWG (3.5mm). I am sure the installers would have done the wiring but I wanted to do it myself.
Above you can see the connections between the indoor and outdoor units; two insulated copper refrigerant lines, a drain line and power line.
Each of these rooms also has a Hunter ceiling fan. Ceiling fans are much cheaper to run than air conditioners and even when the air con is on, keep the ceiling fans running. That way you’ll be comfortable using less air conditioning.
It’s early February now and the nights are wonderfully cool. The gardenias outside our window are blooming and spreading their fragrance which wafts into our bedroom through the open windows. The crickets are serenading us. For now we have very little reason to close our windows, seal ourselves inside and turn on our shiny new air con units and in fact we’ll be sad to do so.
But, few foreigners who live in the Philippines live in such a quiet rural place as we do. A major attraction of air conditioning, besides keeping cool, is that it is just about the only way to reduce or escape noise and pollution. A good night’s sleep may only a dream in the face of roosters, loud music, karaoke and roaring jeepneys. Even if it’s not so hot, as every hotel guest knows, the impulse to close the windows to the noise and be lulled asleep by the white noise of the air conditioner can be irresistible.
We’ll have to wait to give a conclusive report on how well the units work and how much they cost to run. With no air conditioning, we consistently use about 300 KWH per month which costs us about P3,000 per month. When we used the split air con units at our apartment, we were surprised at how little they cost to run. That because we generally set the desired temperature at 29 or 28C. Supposedly each degree of additional cooling adds about 15% to the power consumed so setting the thermostat at 24C would cost 60% more than our 28C setting. When you size your unit, keep your cooling preferences in mind.
UPDATE and WARNING: We were unhappy to find that the Samsung inverter unit which was actually installed for us was NOT rated at the 13,650 kJ/hr capacity given on the specifications section of the Samsung website — the specifications which led us to buy the unit. Our unit’s label gives a rating of 11,630 kJ/hr. AFTER we bought our unit the Samsung website was revised to show the cooling capacity of the 1.5 HP ASV12ESLN as 11,630 kJ/hr rather than 13,650 kJ/hr that was listed when we bought our unit. See http://www.samsung.com/ph/consumer/home-appliances/air-conditioner/split-type/ASV12ESLNXTC/index.idx?pagetype=prd_detail&tab=specification
This is not a theoretical issue. Our unit works to cool our 25 square meter bedroom. When it’s hot outside it struggles to get the temperature below 80F (27C). The industry standard design temperature is 75F/24C. There is no way our unit will cool to 24C (75F) on a hot day, no matter how long it runs. The “missing” 2,000 kJ /hr would give us a unit which would do a better job. We have raised this issue with Samsung in Manila. They corrected the specifications on their web site but otherwise were not especially helpful. It’s no surprise that the top complaint on Samsung’s support page for this unit is, “Why is the room not cold enough even after the air-con has been running for few hours?”
Had we know the true cooling capacity of the Samsung 1.5 HP unit, we would have considered getting the 18,000 kJ/hr 2 HP unit. Because we tend to to be satisfied with 26C or 27C room temperatures, the Samsung 1.5 HP unit may be adequate for us, but it definitely would not do if we wanted 24C.
Bottom line for us is that we wish we had bought the Panasonic units and would have done so is Samsung had not given us incorrect but tantalizing cooling capacity rating for its units. We are fairly happy with the small Samsung conventional unit but less so with the Samsung inverter unit we bought. Samsung advertises that the units are compact but that seems to mean that the fins on the inner evaporator and outer condenser units are packed close together. To us it seems that the fins are more easily damaged and clogged with debris and may require more maintenance. Our one-HP Samsung unit seems better in the regard. The fins have a blue coating which seems to be resisting corrosion better than the tightly packed fins on our Samsung converter unit. Also, after to years, the Samsung inverter is showing signs of less than stellar material quality. The case screw and bolt heads are rusty, the case itself is also starting to rust. The Chinese made non-inverter unit seems better made.