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Msradell
Premium Member
join:2008-12-25
Louisville, KY

Msradell to chmod

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Re: Another a/c issue.

An air conditioner should be able to return here about 20° cooler than the air it takes in, not than the outside temperature. If you don't think it's true just go to Las Vegas in the heat of the summer. It's 110°+ outside yet inside is extremely cool 70° in many cases.

You need to check the temperature of the air and a return and compare it to the temperature of the air coming into the house from the unit. You should see at least 15° and more likely 20° temperature differential between the to. While the outside temperature has some affect it's not huge. If you have the correct temperature differential look elsewhere for your problems, I'd certainly start with insulation and air leaks! It could also be a sizing issue for the AC unit. Are you sure the outside unit is matched correctly for the inside unit? Being different suppliers would lead me to believe they may not be.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

Jack_in_VA

Premium Member

=Msradell See Profile

An air conditioner should be able to return here about 20° cooler than the air it takes in, not than the outside temperature.

It's 92 here today my discharge is 60 degrees the return is 75. 15 degrees. The same as it is when the temp is 80 deg outside.

If you don't think it's true just go to Las Vegas in the heat of the summer. It's 110°+ outside yet inside is extremely cool

You can bet they aren't using freon based mechanical air conditioning. They Probably are using Absorption Liquid Chillers. These chillers can supply 40-45 degree liquid coolant to any number of air handling units to overcome the heat in Las Vegas.
quote:
Absorption chillers use heat to drive the refrigeration cycle, they produce chilled water while consuming just a small amount of electricity to run the pumps on the unit. Absorption chillers generally use steam or hot water to drive the lithium bromide refrigeration cycle but can also use other heat sources.
Most likely Direct-fired absorption chillers that offer customers a choice in how they consume energy to produce chilled water. The chiller uses natural gas or other fuels to fire the absorption refrigeration cycle.

A direct-fired absorption chiller can be used as a primary component for hybrid plants or other applications where electrical demand and consumption are expensive or in short supply.

The efficiency of the double-effect cycle used in these chillers makes them competitive with electric chillers in many regions of the world where electricity prices have risen dramatically over the last decade. All sizes also can act as a chiller/heater to supply chilled or hot water for conditioning the building during the summer or winter.

Beezel1
@cox.net

Beezel1 to Msradell

Anon

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Here in Vegas most houses use freon based mechanical air with supplemental evaporative cooling (swamp cooler). Electricity here is expensive most houses keep at 76 to 78 degrees f. Large businesses use chillers and keep temps in the high 60's to low 70's. I have a 4 ton heat pump without a (swamp cooler) in a 1500 sq. ft. two level town house. It cycles normally and keeps us at a comfortable 76 degrees f. in 110+ temps. Plus in the spring to summer we only have 5 to 10% humidity.
08034016 (banned)
Hallo lisa Aus Amerika
join:2001-08-31
Byron, GA

08034016 (banned) to Msradell

Member

to Msradell
said by Msradell:

An air conditioner should be able to return here about 20° cooler than the air it takes in, not than the outside temperature. If you don't think it's true just go to Las Vegas in the heat of the summer. It's 110°+ outside yet inside is extremely cool

That's about right it was in my City 107F and inside my home it was 74-75F.

My system ran 14Hrs straight with that Temp, we're having a Cooling Trend here now Low to upper 90's
Maniak
join:2008-03-29
Vail, AZ

Maniak

Member

That is about how our system runs too.

The temperature split on our 2 stage heat pump is 16F when on the first stage and 21F when on the 2nd stage.

The 1st stage will keep our house at 73F up to about 100F outside temp Once it gets much over 100F the temp inside will climb 2 degrees above the set point and the 2nd stage will kick on. The 2nd stage will bring the temp back down. It doesn't bring it down quick enough to cycle in the hottest part of the day but it will slowly bring it back down. If the 2nd stage were to be used before the inside temp got 2f over the set point it probably would cycle.

~Mark