Air Conditioners Vs Evaporative Coolers - what's better

[GasoLane]

Originally Posted by 347stroker

Do you know the difference between dry bulb and wet bulb temperatures??

Plot them on a psychrometric chart and see what the real temp is....

Erm, which one (bulb) do they use on the telly? Or the Bureau of Meteorology when they tell us the temp?

[347Stroker]

Originally Posted by svo347

Yep the offices had Refrigeration units whilst our Workshops and engine building rooms had Evap units.

Coming from a mining background, and being a stout unionist I would say the staffie maggots got the cream, where the workers and the backbone of the mine got diddly squat....lol

[svo347]

Mate u got an email addy got something to send ya ..???

fastfasty@optusnet.com.au ???????? as long as it aint no bugs!!! LOL...??!!?

[xbgs351]

Originally Posted by xbgs351

-How well is the house insulated?

Originally Posted by 347stroker

+ And how does that differ from swampies

The difference lies in air flow rate. An evaporative air conditioner exchanges the warm air inside the house with fresh cool air in around 2 minutes. Hence it make little difference if the house is insulated or not. This is why evaporative air conditioner can be succesfully used in sheds.

Refrigerative airconditioners (on recirculation) have to pull down the temperature of the air that is already in the house. If the house is poorly insulated, has drafts or open windows, the refrigerative airconditioner will take far longer to cool the house and use far more energy.

Originally Posted by xbgs351

-Does any of the family have asthma?

Originally Posted by 347stroker

+ Is of no concern to A/C, thats an old wives tale full of crap

Not true. Dry air isn't good for asthmatics. The reason asthmatics are encouraged to swim is that the air above the water is very humid. This allows asthmatics to exercise without getting asthma.

Originally Posted by xbgs351

-Does any of your family have allergies?

Originally Posted by 347stroker

+ See above

Evaporative air conditioners supply a continuol supply of fresh filtered air.

Originally Posted by xbgs351

-Do you want the whole house cooled?

Originally Posted by 347stroker

+ That would be a big splittie.....I think you are thinking of ducted air

Evaporative air conditioners are ducted and cool the whole house. To get the same effect using refrigerative air one needs a big splittie or ducted air and the bigger they are the more they cost to run.

Originally Posted by xbgs351

-How often and long will cooling be required?

Originally Posted by 347stroker

+ As long as the customer wants to feel comfortable

If someone wants to have a comfortable nights sleep, the air conditioning may be on for 12 hours. Doing this throughout summer with refrigerative air will result in a horrendous power bill. If however they only have the air conditioner on occasionly, the power bill wouldn't be an issue.

Originally Posted by xbgs351

-Do you already have gas heating?

Originally Posted by 347stroker

+ How does this matter, reverse cycle cost about 30 $ over cooling only

If somebody already has gas heating, a reverse cycle airconditioner offers no or little benefit as far as heating is concerned. If however they have electric heating, a reverse cycle airconditioer would be advantageous.

Originally Posted by xbgs351

-Is there room in the roof for ducts?

Originally Posted by 347stroker

+ And split systems come in where?

If there is no room in the roof for ducts, evaporative airconditioning isn't an option.

Originally Posted by xbgs351

-How handy are you? A lot of the work can be done by someone with the right skills.

Originally Posted by 347stroker

+ Once again, non skilled persons carrying out the jobs best left for the professionals...;

Using that logic do you suggest that we here on this forum shouldn't work on our cars, but should leave it to the "professionals".

If one has the right skill they can perform the majority of the installation themselves. A lot of money can be saved by paying wholesale for an evaporative air conditioner. More money is to be saved by doing the vast majority of the labour yourself.

Originally Posted by 347stroker

I think maybe you should do some more research before you make sweeping statements mate, seeing hospitals have Air Conditioning, and there is no dilemas with asthsma. There is also alot of different types of air conditioners too.....do the research, you are making a fool of yourself.

I'm not afraid of making a fool of myself because I have nothing to loose. You on the other hand work in the industry and do have a lot to lose. You may suggest that I do some research and I will suggest that you do some as well. You may have a good understanding of the mechanics behind airconditioning, but you have demonstratred a lack of understanding behind the thermodynamics behind airconditioning.

For example:
-You said that evaporative air conditioners do not reduce the air temperature, when they do.
-You said that refigerative air conditioners remove minimal mositure from the air, which is not true.
-You suggested that dry bulb temperature is not the real temperature, when it is.
-You said that a refrigeration system uses latent heat of enthalpy to achieve results. That is like saying the sun uses mass to achieve results.

Originally Posted by 347stroker

They dont call refrigeration and Airconditioning the 8th wonder of the modern world for nothing...

Did you know that refigeration was invented by James Harrison in Geelong? I can never understand why when told to think of important Australian inventions, people think of the Victa and the Hills Hoist. The Hills Hoist wasn't even invented in Australia.

Originally Posted by 347stroker

And to shoot down your sweeping generalisation of A/C's dont work in dry climates, I lived in Central QLD for many years where it would make your place look like an oasis, and bugger me, every donga, house, office and shop had A/C too....twenty years earlier they had swampies, but with the advent of technology, they all dissappeared.....
Try asking any guys that work in the mines in CQ, NT or WA what they have........and they are the dryest climates in all of Australia...

Water is a lot more scarce in a lot of the places you mentioned, which makes using it for an evaporative airconditioner an unattractive proposition.

Originally Posted by 347stroker

I run an Air Conditioning company here in QLD and know the figures of Air Conditioners being imported into australia every year as a whole and the numbers are just mind numbing.

The reason that the majority of the air conditioner imported into Australia are imported is because the majority of evaporative air conditioners are Australian made.

[xbgs351]

Originally Posted by xbgs351

The reason that the majority of the air conditioner imported into Australia are imported is because the majority of evaporative air conditioners are Australian made.

Should have read:

The reason that the majority of the air conditioners imported into Australia are refrigerative is because the majority of evaporative air conditioners are Australian made.

[Kingsley]

We've had both at different times. Just out of personel experience, the air cond is better than evaporative.

[EL XR8]

Well i'm in Melb, so the climate is pretty much the same as Canberra.
I install Split Systems and Box Airconditioners (I'm a sparky) and my old lady has an Evaporative Unit at home.
Although the evap units work, they are no where near as effective as a split system, yes i would honestly think that they are cheaper to run over the same time period. Thats just common sense from their comparitive power usage.
But the Refrigerated air-cons do not need to be run for the length of periods as the Evaporatives.
You need to have the Evap units running for hours on end, and have them running at the start of the day (if its going to be hot) because once your house is hot inside, they wont be able to cool it down, no matter how fast the fan is going, it just wont happen, and if it does, it takes hours.

It will come down to cost, as Evap do work, but not really that well, they'll cool the house and have a cheap installation price, but in balck and white, they do not and will not ever work as well as a Refrigerated unit.
No one would be able to dispute this.... If you came home, even early in the arvo on a hot day, and went to turn the Evap unit on, it would not cool your house down for hours, if being able to do it at all. I know i live in a house with one! Whereas, if you came home and turned on a Refrig unit, it would more than likely cool the house down within 15 mins or less.

There is no doubting that Refrig Aircon is better and more effective.
It is going to be double the price to install, but it wouldn't be that much more expensive to run.
When i build a house in the future it will definately have Refrig Aircon over Evap, as long as i can afford it.

It should really be a price thing for you to decide.
Hope that helped mate.

[rag top]

Thanks to all for your advice and comments.

We've decided to go with a reverse cycle refrigerated unit for the open plan living area, and get ducted evaporative cooling to go with the ducted heating throughout the whole house.

[MITCHAY]

Were getting ducted evapourative cooling put in on Tuesday week. Can't wait. It's 28 degrees in my house at the moment.

[Electric]

Originally Posted by xbgs351

If somebody already has gas heating, a reverse cycle airconditioner offers no or little benefit as far as heating is concerned. If however they have electric heating, a reverse cycle airconditioer would be advantageous.

Not really, I live in Canberra and my house has gas ducted central heating, and a reverse cycle AC in the family room.

When it is before or after the middle of winter and it is cold at night but not 'THAT' cold then we crank up the reverse cycle to take the chill off the living areas, without having to heat the entire house. Then put a Doona on in bed.

For the other guy who suggested that "Melb, so the climate is pretty much the same as Canberra."

Has obviously never been here in winter, the minimum temp at melb airport is -2.5 deg, at Canberra Airport the min is -10 deg.

Perhaps they are similar for a few weeks in the middle of summer but thats about it. Anyone who lives in Canberra and makes decisions about comfort in their house in summer without considering winter needs there head read.

Its uncomfortably hot for a total of about 20 odd days or 3 weeks, its freezing cold for over 2 months.

[MITCHAY]

Originally Posted by Electric

Not really, I live in Canberra and my house has gas ducted central heating, and a reverse cycle AC in the family room.

When it is before or after the middle of winter and it is cold at night but not 'THAT' cold then we crank up the reverse cycle to take the chill off the living areas, without having to heat the entire house. Then put a Doona on in bed.

Should give that doona tip to my brother. Woke up one morning and the little s**t had pumped the ducted heating up. Looked at the control unit and sure enough it was 45 degrees.

[rag top]

Originally Posted by MITCHAY

Should give that doona tip to my brother. Woke up one morning and the little s**t had pumped the ducted heating up. Looked at the control unit and sure enough it was 45 degrees.

Now that's as warm as toast!!

[StorminaTcup]

We have the evap cooling, and I would suggest that if someone thinks it takes hours to cool then they do not have the correct size unit installed. Ours does not take hours to cool the house.

[xbgs351]

Originally Posted by Electric

Anyone who lives in Canberra and makes decisions about comfort in their house in summer without considering winter needs there head read.

Its uncomfortably hot for a total of about 20 odd days or 3 weeks, its freezing cold for over 2 months.

Very good point.

[CarBroker]

I have found that refrigeration is more powerful, but evaporative is more comfortable. Dry air is no good for your skin.

So.... if your house is well designed and has the right aspect it won't get all that hot anyway, and you can get away with evap cooling. That would be my preference, but my current house has windows in the wrong places and is just stupidly designed, so I have a hugely oversized aircon system that still struggles to keep the house cool.

[nang3]

i have the perfect mix in my house, fully ducted evap in every room... plus a 1.5hp reverse cycle for the bedroom, and 4hp revcyc for the main living area.. this big mofo does cool the entire house after about an hour of operation..

I had originally planned to use the evap for non humid days and R/Cycle for humid hotter days but after about 2 days use i no longer use the evap for anything except providing some ventilation on coolish nights... R/C is just so much better and yes it costs a bit more, but i have only noticed my powerbill increase by about $50 in the hottest months

[pauljh74]

Originally Posted by CarBroker

I have found that refrigeration is more powerful, but evaporative is more comfortable. Dry air is no good for your skin.

So.... if your house is well designed and has the right aspect it won't get all that hot anyway, and you can get away with evap cooling. That would be my preference, but my current house has windows in the wrong places and is just stupidly designed, so I have a hugely oversized aircon system that still struggles to keep the house cool.

Maybe invest in roller shutters - good for cutting down noise too.

[pajamas]

Originally Posted by '67

Thanks to all for your advice and comments.

We've decided to go with a reverse cycle refrigerated unit for the open plan living area, and get ducted evaporative cooling to go with the ducted heating throughout the whole house.

I was wedded to A/C when living in Bubdaberg, Queensland, and saw how evaporative units just didn't cope.

My partner insisted on evap when we moved to Canberra. My view was that we were wasting our money and would end up having to get a A/C unit in the end anyway.

We'll I now LOVE the Evap unit and in the past five years , there has been only 1 day when it hasn't worked beautifully. On the recent 43 degree days, the house was a comfortable 25.

I'm cooped up in an office all day, so I really like the fresh air breezing throught the house. After work, it only takes about 10 minutes to blow the hot air out of the house.

Could I suggest that if you are going to get evap fitted, that you get in the entire house (unless there is some engineering reaon to preventing this).

Save the $$$ you were going to spend on the A/C unit for the open plan parts of the house. See how it goes. You can always buy the the A/C unit at a later date.

I find evap in Canberra very effective and cheap to run - we happily run it all day and don't worry how much it's costing us.

My hope is that you will be impressed by the evap unit.

Cheers

Paul

[rag top]

Originally Posted by pajamas

Could I suggest that if you are going to get evap fitted, that you get in the entire house (unless there is some engineering reaon to preventing this).

I'm definately getting evap fitted to the entire house, and around the same time getting ducted gas heating fitted. (inlaws are paying for the ducted gas heating : )

But we thought about how we use the house, and with the wife at home with the kids during the day, it would be a better option to get the reverse cycle for both winter and summer in the living areas. It is a year round solution, not just for summer.

[rodderz]

Just bringing up an old thread here guys instead of starting a new one...

Those who have installed a reverse cycle wall-mounted split system with the refridgerant unit placed directly outside the internal wall it is located, what's a rough idea of install price?

Looking at getting one before xmas

[Laminge]

Depending on what eletrical work is required, I have paid between 400 and 600

Cheers

[rag top]

Phone around for an install quote; I saved a couple of hundred dollars by comparing prices amongst a couple of installers.

[XR6-VCT-2000]

Originally Posted by Mrs347stroker

My hubby installs air-cons for a living and he would never recommend evaporative cooling. Go with cooling air-con, you can't go wrong.

funny you mention that , i used to work for a company that makes evaporative cooling and i recon refrigerated is still better too, even the company agreed refrigirated was better (quietly to themselfs !) , they just decided to make them as it was a way to make extra $$ by adding it to the ducting heater system they make too !, with slightlly different duct pipes ( usable for hot and cold air ).
Im not gonna name the company as they still make both these days too !

[TURBOTAXI]

I have not read the whole thread, but refridgerated air is the way to go.

[AC/DC]

In North Queensland it would be 99% AC and 1% Evap.

Those 1% with Evap would be wishing they had AC.

Evap is completely useless in the humid conditions on the tropics.

AC/DC

[Dazza XLT]

Agreed. Once the humidity kicks in, Evap is pointless.
Refrig AC is the only way to go. Split systems are quite cheap to run these days.

[rodderz]

I have got a few quotes today on a couple of reverse cycle splits, one has recommended fujitsu and the other Carrier. Both seem to be at the high end of the market and the quotes are within a few hundred $ of one another, now just have to decide which unit.

I did ask both about evaporative as I wouldnt have an issue with that, but it's an extra couple of grand or so to do each room in the house, plus it's only cooling and the split will do heat & cooling