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Huh, interesting. Thanks.

Originally Posted by hvacrmedic

The water vapor displaces other heavier molecules, reducing the overall density of the gas mixture. Just imagine filling a room with helium (at constant pressure). As the helium content rises the density of the mixture in the room will drop, and the room will gain lift like a helium balloon.

Less dense air will be poorer at transferring heat from an air over heat exchanger like a finned coil. Aircraft will also have less lift. A helicopter can land on a high peak in dry air, and be unable to get back off the ground later due to higher humidity alone. It has happened, or so I've heard.

If you are trying to say that balance point does not depend on location, then yes.

Originally Posted by richper

B. Beerme . In post # 52 you are in agreement with me . Correct ?

That's why I repeatedly said same unit and same structure.

Originally Posted by BNME8EZ

The one thing and it is very important in this discussion is we are talking everything being the same for house and equipment only the location is different. We all know that in reality the house in Texas will have a much larger cooling load and the house in Canada will have a much larger heating load so the equipment would be very different which would then cause the houses to have very different balance points. Not because of temperature or location but because of equipment capacity.

The one thing and it is very important in this discussion is we are talking everything being the same for house and equipment only the location is different. We all know that in reality the house in Texas will have a much larger cooling load and the house in Canada will have a much larger heating load so the equipment would be very different which would then cause the houses to have very different balance points. Not because of temperature or location but because of equipment capacity.

Originally Posted by BBeerme

How does that work?

I guess you could say less air. Because in the extreme, it would be all water and no air.

So instead of saying air, let's call it a medium or substance. As the moisture content of this substance increases, and given a normal AC under normal conditions, does this substance remove more or less heat from the outdoor coil?

The water vapor displaces other heavier molecules, reducing the overall density of the gas mixture. Just imagine filling a room with helium (at constant pressure). As the helium content rises the density of the mixture in the room will drop, and the room will gain lift like a helium balloon.

Less dense air will be poorer at transferring heat from an air over heat exchanger like a finned coil. Aircraft will also have less lift. A helicopter can land on a high peak in dry air, and be unable to get back off the ground later due to higher humidity alone. It has happened, or so I've heard.

I going back to my tequila

B. Beerme . In post # 52 you are in agreement with me . Correct ?

Originally Posted by BBeerme

He'll get it. As The Medic stated, he just needs to step back and relax.

I have the book in front of me, I completely get it What BNME8EZ says is right.

Originally Posted by BNME8EZ

If you look at the heat lose of a structure it is a linear process. So as the temperature goes down the heat needed goes down to match. This is why location does not matter. The lose will be the same at 47 degrees whether it is located in Texas or Canada. At 0 the heat lose will be the same in both locations. The output of the same unit at both locations will be the same. The difference comes in where in Texas you may never reach the point where the unit will need the back up heat where as in Canada it will probably quite a bit. I think where the confusion is the house will have more heat lose at design in Canada than Texas because of colder design conditions.

Correct, I agree, however, we both know you are not getting zero degrees in texas! and yes on your last sentence, if you have more heat loss at design you would have 2 different balance points at a colder design condition! There is a chart that can be made to show that.

He'll get it. As The Medic stated, he just needs to step back and relax.

Originally Posted by BNME8EZ

If you look at the heat lose of a structure it is a linear process. So as the temperature goes down the heat needed goes down to match. This is why location does not matter. The lose will be the same at 47 degrees whether it is located in Texas or Canada. At 0 the heat lose will be the same in both locations. The output of the same unit at both locations will be the same. The difference comes in where in Texas you may never reach the point where the unit will need the back up heat where as in Canada it will probably quite a bit. I think where the confusion is the house will have more heat lose at design in Canada than Texas because of colder design conditions.

How does that work?

I guess you could say less air. Because in the extreme, it would be all water and no air.

So instead of saying air, let's call it a medium or substance. As the moisture content of this substance increases, and given a normal AC under normal conditions, does this substance remove more or less heat from the outdoor coil?

Originally Posted by hvacrmedic

You have no idea what thermal balance point is, even after posting its definition yourself. Clear your mind, take in a few slow deep breaths.

The thermal balance point works like this. As the outdoor temp drops the heating capacity required to maintain the indoor temp increases. Unfortunately as the outdoor temp drops the heat pump's capacity drops. As a result an outdoor temperature will be reached where the heat pump must run nonstop just to maintain the indoor temperature, and if the outdoor temp drops any more than that the heat pump will not be able to keep up, and the indoor temp will begin to drop as well. This crossover outdoor temperature is called the thermal balance point. If the temperature is -10° in one location but only 20° in another, this has nothing to do with the balance point other than the fact that you'll be further below the balance point in one location than in the other.

BTW in reference to a
post on page one, higher humidity usually results in "less" dense air.

Originally Posted by hvacrmedic

You have no idea what thermal balance point is, even after posting its definition yourself. Clear your mind, take in a few slow deep breaths.

The thermal balance point works like this. As the outdoor temp drops the heating capacity required to maintain the indoor temp increases. Unfortunately as the outdoor temp drops the heat pump's capacity drops. As a result an outdoor temperature will be reached where the heat pump must run nonstop just to maintain the indoor temperature, and if the outdoor temp drops any more than that the heat pump will not be able to keep up, and the indoor temp will begin to drop as well. This crossover outdoor temperature is called the thermal balance point. If the temperature is -10° in one location but only 20° in another, this has nothing to do with the balance point other than the fact that you'll be further below the balance point in one location than in the other.

BTW in reference to a
post on page one, higher humidity usually results in "less" dense air.

Gotta read the post I quoted in that to fully understand what I meant. I know its not something you set or change and know it's the point at which your output equals your loss.

If you look at the heat lose of a structure it is a linear process. So as the temperature goes down the heat needed goes down to match. This is why location does not matter. The lose will be the same at 47 degrees whether it is located in Texas or Canada. At 0 the heat lose will be the same in both locations. The output of the same unit at both locations will be the same. The difference comes in where in Texas you may never reach the point where the unit will need the back up heat where as in Canada it will probably quite a bit. I think where the confusion is the house will have more heat lose at design in Canada than Texas because of colder design conditions.

Originally Posted by lkapigian

The heat out out of the equipment has nothing to do with the efficiency of the structure ...it has to do with OSA DB if I have less heat loss at lower temperature my heat output of the machine remains the same at can keep up with the load at lower temprature ....same as cooling the better the structure the smaller ac can keep up at higher temps

I know that, I repeated what you stated about making the home more efficient.

Doesn't matter what the outdoor temp is, the balance point remains the same. There are only three possibilities. You are at, above, or below the balance point. Whatever temp the balance point is, makes no difference where you are.

You're going to drive a man to drink.

Think I'll go buy some food for dinner now so I can start drinking when I get home, LOL.

Originally Posted by psehunter

I'm confused, what's the answer? That was already said earlier what thermal balance point was, I'm trying to figure out how that answer addresses what you said about 2 structures in 2 different places (with 2 different outdoor temps obviously) would have the same balance point.

Originally Posted by psehunter

You mean raise the BP. If you lower it ie; 32 degrees to 20 degrees, that means you have more heat loss. If your home is more efficient, you have less heat loss which would require less output to match the loss.

The heat out out of the equipment has nothing to do with the efficiency of the structure ...it has to do with OSA DB if I have less heat loss at lower temperature my heat output of the machine remains the same at can keep up with the load at lower temprature ....same as cooling the better the structure the smaller ac can keep up at higher temps

Originally Posted by psehunter

You mean raise the BP. If you lower it ie; 32 degrees to 20 degrees, that means you have more heat loss.

You have no idea what thermal balance point is, even after posting its definition yourself. Clear your mind, take in a few slow deep breaths.

The thermal balance point works like this. As the outdoor temp drops the heating capacity required to maintain the indoor temp increases. Unfortunately as the outdoor temp drops the heat pump's capacity drops. As a result an outdoor temperature will be reached where the heat pump must run nonstop just to maintain the indoor temperature, and if the outdoor temp drops any more than that the heat pump will not be able to keep up, and the indoor temp will begin to drop as well. This crossover outdoor temperature is called the thermal balance point. If the temperature is -10° in one location but only 20° in another, this has nothing to do with the balance point other than the fact that you'll be further below the balance point in one location than in the other.

BTW in reference to a
post on page one, higher humidity usually results in "less" dense air.

Originally Posted by BBeerme

Ding, ding, ding . . .

And we have a winner folks !!

I'm confused, what's the answer? That was already said earlier what thermal balance point was, I'm trying to figure out how that answer addresses what you said about 2 structures in 2 different places (with 2 different outdoor temps obviously) would have the same balance point.

Originally Posted by lkapigian

You can lower the balance point of any heat pump by increasing the efficiency of the home...it not just about the efficiency of the equipment...when the load matches the output, you are at the balance point

You mean raise the BP. If you lower it ie; 32 degrees to 20 degrees, that means you have more heat loss. If your home is more efficient, you have less heat loss which would require less output to match the loss.

Originally Posted by BBeerme

Ding, ding, ding . . .

And we have a winner folks !!

Cheers my friend