Do Evap-coolers & AC Both Work Same Principals? - HVAC - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 08-30-2014, 03:43 AM   #1
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


If so why hasten any AC companies found a way to create a system that automatically switches from AC to evaporative cooling automatically since evaporative cooling is 5-10 times more efficient than traditional AC “WHEN” conditions are right.


I'm so tired of having to check the local weather forecast for Barometric pressure, Dew Point, and Humidity. Then go through the agony of between AC to Evaporative cooling by opening and closing vents and windows and turning water supply on and off.


After all an evaporative cooler works on the same principal as any AC unit, but only when there is a high pressure atmosphere, low dew point and low humidity can this miracle of evaporative cooling occur. Withe respect to an evaporative cooler high pressure atmosphere acting as the compressor with its high pressure dry air is drawn is catapulted by the blower fan through the wet straw intake panels acting as an evaporator. The high pressure dry air colliding with the water molecules respond like a refrigerant and undergo a rapid change of state from a liquid to a high volume gas resulting in a rapid temperature drop within and exiting the evaporative cooler exhaust vent from between 40-50F (110F outside- 58F at the supply vent). This happens according to Boyle's Law PV=K, where P is the pressure of the gas, V is the volume of the gas, and k is the temperature.

Advertisement

CWO4GUNNER is offline   Reply With Quote
Old 08-30-2014, 05:58 AM   #2
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,523
Rewards Points: 4,684
Default

Do Evap-coolers & AC both work same principals?


Evaporative coolers require a large volume of air. Vapor compression doesn't.
Evaporative needs the windows open, vapor compression needs the windows closed.

So to do what you would like to see. Large exhaust ducts would be needed in all rooms, and have to have motorized dampers on them. An automation control system that would not be real cheap. Plus, it would only work in a relatively limited amount of areas.

Advertisement

__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 08-30-2014, 11:31 AM   #3
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


Yup AC is a closed system and evaporative cooling is an open system. My late HVAC instructor told a story of a company back in the day like 30 years ago who had sold such a system that used a large vacuum operated devertion dampner pwered off the blower intake side and like on a car AC that open or close deverting return air from either the conditioned space or from an evaporative cooler inside the attic next to the air handler. Also a solonoid would unlock ceiling vents which then operated by supply air pressure and gravity. Once switch back over to AC, again the blower intake vacuum at the fan would move the large dampner cutting off supply air from the adjacent evaporative cooler to return air circuit. Then blower would stop momentarily allowing all ceiling vents to the hot attic to drop locked by solinoid and blower would restart AC. The blower powered both AC supply air and evap cooler box. But no one hardly bought them back then because energy was cheap so they stop making them. But today it would be ideal hear in the Southwest.
CWO4GUNNER is offline   Reply With Quote
Old 08-30-2014, 11:46 AM   #4
Hvac Pro
 
Join Date: Nov 2008
Location: Winnipeg, Canada
Posts: 10,112
Rewards Points: 862
Default

Do Evap-coolers & AC both work same principals?


The more complex you make it the more it breaks down and is expensive to repair. Once you add a bunch of solenoids and damper motors those suckers eventually fail and wear out. At $100-$150 an hour for labor to fix them plus materials and travelling time the appeal goes away in a hurry. May be OK for huge Commercial apps but there are more efficient ways to cool them. The market share would be so small none of the major players/ Carrier etc would want to invest huge R@D dollars in anyway.
__________________
"Cut it twice and it is still too short".
yuri is offline   Reply With Quote
The Following User Says Thank You to yuri For This Useful Post:
ben's plumbing (08-31-2014)
Old 08-30-2014, 12:23 PM   #5
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


I don't know, vacuum motors are pretty reliable in cars and Iv almost never hear of a solinoid failure, not may parts if you can Invision it. The only problem I would see would be evaporative cooler drainage and vented humidity to the attic in moist climates. Other then that a split system by itself is already unnecessarily too complicated compared to a packaged unit and even more so compared to a ductless split system. Perhaps using ductless split systems all that would be needed is a simple logic circuit to power down the AC and power up the evaporative cooler using local forecast information.
CWO4GUNNER is offline   Reply With Quote
Old 08-30-2014, 03:32 PM   #6
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,523
Rewards Points: 4,684
Default

Do Evap-coolers & AC both work same principals?


Quote:
Originally Posted by CWO4GUNNER View Post
I don't know, vacuum motors are pretty reliable in cars and Iv almost never hear of a solinoid failure, not may parts if you can Invision it. The only problem I would see would be evaporative cooler drainage and vented humidity to the attic in moist climates. Other then that a split system by itself is already unnecessarily too complicated compared to a packaged unit and even more so compared to a ductless split system. Perhaps using ductless split systems all that would be needed is a simple logic circuit to power down the AC and power up the evaporative cooler using local forecast information.
Most ductless splits use inverters. They are technically more complicated then a standard split A/C.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
The Following User Says Thank You to beenthere For This Useful Post:
ben's plumbing (08-31-2014)
Old 08-30-2014, 08:27 PM   #7
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


Yes but inverters are solid state electronics, easy diagnosis, easy fix. However you did inadvertently remind me that of all the reviews I have read on mini-split systems, the ones with the highest reliability rating where there was no compressor motor speed issues i.e running too slow/inverter failure, were all units without inverters. Hence I decided to play it safe and buy my first no inverter model and sacrifice some seer rating..
CWO4GUNNER is offline   Reply With Quote
Old 08-30-2014, 09:34 PM   #8
I'm Your Huckleberry
 
Join Date: Mar 2011
Posts: 5,884
Rewards Points: 2,270
Default

Do Evap-coolers & AC both work same principals?


what's the question, why do ac's exist?

why does electricity exist, light bulbs, cars, life itself? What?
__________________
Thanks.
Doc Holliday is offline   Reply With Quote
Old 08-31-2014, 12:08 AM   #9
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


Quote:
Originally Posted by Doc Holliday View Post
what's the question, why do ac's exist?

why does electricity exist, light bulbs, cars, life itself? What?
Nope Doc, and its not about chickens, cows, pigs or horses neither. Best bet is to read twice and answer once. Sort of like the measuring rule.
CWO4GUNNER is offline   Reply With Quote
Old 08-31-2014, 12:28 AM   #10
I'm Your Huckleberry
 
Join Date: Mar 2011
Posts: 5,884
Rewards Points: 2,270
Default

Do Evap-coolers & AC both work same principals?


well let's see then; both release heat during a change of state as both are one and the same so yes.

egg before chicken? I'm confused.
__________________
Thanks.

Last edited by Doc Holliday; 08-31-2014 at 12:31 AM.
Doc Holliday is offline   Reply With Quote
Old 08-31-2014, 08:07 AM   #11
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,523
Rewards Points: 4,684
Default

Do Evap-coolers & AC both work same principals?


Quote:
Originally Posted by CWO4GUNNER View Post
Yes but inverters are solid state electronics, easy diagnosis, easy fix. However you did inadvertently remind me that of all the reviews I have read on mini-split systems, the ones with the highest reliability rating where there was no compressor motor speed issues i.e running too slow/inverter failure, were all units without inverters. Hence I decided to play it safe and buy my first no inverter model and sacrifice some seer rating..
Solid state has no in between. If its working while your there, no way to test it.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
The Following User Says Thank You to beenthere For This Useful Post:
ben's plumbing (08-31-2014)
Old 08-31-2014, 09:31 AM   #12
Hvac Pro
 
Join Date: Nov 2008
Location: Winnipeg, Canada
Posts: 10,112
Rewards Points: 862
Default

Do Evap-coolers & AC both work same principals?


Inverters are good ONLY if you buy a HIGH quality unit like a Fujitsu. They have VERY well built circuit boards and voltage regulators etc. There has to be large proper heat sinks on the board and coated with proper heat transfer grease etc or the boards die. Not going to get that from your el cheapo Asian junk.

I took a course on Fujitsu's and you have to know how to check DC voltages and understand some basic electronics.

Within 10 yrs the price may come down on the compressors as the market share goes up but the market for mini splits is small. There are people who are willing to pay top $$ for Fujitsu quality and buy Lexus cars etc. Fuji has it's well established long term market and is not going to soil it's reputation by dumbing down the quality to compete with the el cheapo's.

As the government requires higher SEER units inverters may be necessary as the physical size of high SEER units is so huge it may have to end or they will be the size of a garden shed.
__________________
"Cut it twice and it is still too short".
yuri is offline   Reply With Quote
Old 08-31-2014, 11:57 AM   #13
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


Well yes solid state is pretty much diagnose and replace when it comes to boards.

As far as one brand mini-split better then the other, while I agree this is true to a point, I just don't see the disparity between brands being that far apart in customer reviews when it comes to ductless mini-splits as with other technologies like heavy industries for example Chinese VS Japanese with respect to scooters, motorcycles, and cars. But when it comes to light industry the Chinese have really caught up enough becasue of small Japanese/Chinese joint ventures that the price differences are more do to cheap Chinese/Indian labor than anything else. In other-words the quality gap between my Japanese-technology/Indian-labored $700 Pioneer unit will perform well enough against a similar rated Japanese technology/Japanese labored Fujitsu/Mitsubishi/Toshiba $3000 unit, but the former reaping huge initial investment saving of $2300 which is enough to buy 3 spare Pioneer machines, that is an unignorable value IMO.
CWO4GUNNER is offline   Reply With Quote
Old 08-31-2014, 12:07 PM   #14
Member
 
Join Date: Aug 2014
Location: Arizona
Posts: 203
Rewards Points: 197
Default

Do Evap-coolers & AC both work same principals?


Anyway back on topic, I think the only way to merge AC and evaporative cooling will be in conjunction with these mini split systems that do no rely on duct-work. Old ceiling duct vents can easily be retrofitted to support evaporative cooling exhaust or supply depending upon your installation attic or through-wall. Added DIY wifi controls will be able to monitor local weather humidity levels automatically twitching between AC and evaporation cooling increasing efficiency so high to offset any noticeable differences between 15 and 20 seer ratings touted AC units.
CWO4GUNNER is offline   Reply With Quote
Old 08-31-2014, 12:09 PM   #15
I'm Your Huckleberry
 
Join Date: Mar 2011
Posts: 5,884
Rewards Points: 2,270
Default

Do Evap-coolers & AC both work same principals?


this cwo lady reminds of my former self.

for every action there is an equal and opposite reaction. ??

I sell and I sell at twice the price for the exact same equipment. your 2k offensive is chump change and not worth batting an eye at.

foreign? domestic? I doubt you even know the difference, but brand name matters not, I do. I sell, cause I know.

Advertisement

__________________
Thanks.
Doc Holliday is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pulling permits -- getting caught on previous UN-permitted work and effect on taxes jpfulton248 General DIY Discussions 11 01-22-2013 04:58 PM
HELP, Please.. Do I really need this work done???? jeminnick Electrical 34 01-04-2013 01:41 PM
DIY Duct work for old house? Ocelaris HVAC 12 10-17-2012 11:32 PM
Seer 10 evap coils bad, Go to Seer 13??? pcumming HVAC 5 09-01-2010 06:21 PM




Top of Page | View New Posts