Energy efficiency improvement of an air conditioner by integrating Water FOG system has been implemented since 2004 to date because the concepts is of unbeatable performance, EER 19.5, none of existing air-cooled air conditioner can ever reach this point.  Still, there are questions and concerns we can help you to get through all of them straight forward rationally.


Q: Is it worth enough to use Water FOG system in long term?

A: Yes

In the graph on the left,  in 10 years:


Normal A/C would used up 218,070 Baht (Initial cost 18,000 Bt + energy cost 200,070 Bt = 218,000 Bt.)


A/C with FOG would used up 145,990 Baht (Initial cost 28,000 Bt + energy cost 117,990 Bt = 145,990 Bt.)


Savings = 82,080 Bt can reasonably compensate any drawbacks over the entire life of the unit (see spread sheet on the right.


FOGMAN Air conditioner achieved EER 19.5
Credit: DAIKIN Industries

Credit: DAIKIN Industries

What is COP, EER : definition and formula?

COP = Coefficient of Performance, ratio used to evaluate efficiency of heating or cooling systems.
COP = Output heating or cooling in Wh / input electrical energy in Wh
Note that for cooling system it is better to use EER coefficient. The relation between EER and COP is :
EER = COP * 3.41

What is EER : definition and formula?

EER = Energy Efficiency Ratio, ratio used to evaluate efficiency of cooling systems.
EER = Output cooling in BTUh / input electrical energy in Wh
EER = 1.12 * SEER – 0.02 * SEER2


What is SEER : definition and formula?


SEER = Seasonal Energy Efficiency Ratio, this ratio is also used to indicates the relative amount of energy needed to provide a specific cooling output. It is expressed in BTU/Whr
SEER represents the expected overall performance for a typical year’s weather in a given location. It is calculated with the same indoor temperature, but over a range of outside temperatures from 65 °F (18 °C) to 104 °F (40 °C), with a certain specified percentage of time in each of 8 bins spanning 5 °F (2.8 °C). There is no allowance for different climates in this rating, which is intended to give an indication of how the EER is affected by a range of outside temperatures over the course of a cooling season.


SEER = (1.12-√(1.2544-0.08*EER)) / 0.04



In europe : before 2013 air conditionner and heating systems were rated according to EER and COP. These ratio were calculated for only one measurement at full charge.
Since 2013 the ErP directive set SEER and SCOP. They are calculated for 4 measurement In US : For Heat Pump :



Blue hydro-coil coating

Blue hydro-coil coating

Automatic water softener

Automatic water softener

Q: Will condenser coil corroded or clog with scale over time?

No: If you have a good Water FOG system in place.

Y: Yes, if you just have only the misting system without coil treatment.


With the “Hydro-coil coating”  developed since 2009 and “proper” water softening system, you would reduce 95% risk of corrosion and scale deposit problems.


The “Hydro-coil coating” is special formula epoxy-based coating developed specially for use with Water FOG system. It is designed for on-site application, allowing dry ambient temperature for coating to set. It has the following specifications:


Dry film thickness: 25-40 microns

Good adhesion properties

Anti-corrosion properties to extend useful life of the coil

Hydrophilic properties improve cooling efficiency when use in contact with water mist


We recommended to use our automatic water softener for all Water FOG system for the following reasons:


Remove 95% of calcium scale from raw water

Reduce 95% scale deposit on coil, thus cleaning is optimum (Labor cost and corrosive chemical)

Reduce 95% nozzle cleaning

The unit is compact and operate automatically. Almost maintenance free.