Manual J

[bruno812]

So when you find one of these experts who run the Manual J and other calc. when selling you a system.

Is that going to size the unit so it will pull the temp down to a certain temp?

Does it try to size the unit so it will run most of the time during the heat of the day?

I have yet to find a person in Oklahoma that runs these calculation to find out how it does size the systems. I guess this is not only "No Mans Land " but not to many real " AC Men Either"

:CU:

[HPGui]

When done properly, your system will run continuously when the outdoor temp reaches the design temperature for your location. In doing so, it will maintain the indoor target temperature used in the manual J calculation.

[Rickrod3]

So when you find one of these experts who run the Manual J and other calc. when selling you a system.

Is that going to size the unit so it will pull the temp down to a certain temp?

Does it try to size the unit so it will run most of the time during the heat of the day?

I have yet to find a person in Oklahoma that runs these calculation to find out how it does size the systems. I guess this is not only "No Mans Land " but not to many real " AC Men Either"

:CU:

The Idea of the manual J heat load calculation is to size a system that is economical to run and provide comfort.
There are different design parameters for different parts of the country.
They address latent and sensible loads so that temperature and humidity are addressed.
If you follow manual D duct sizing and manual S equiptment selection you will have a top notch system.

[dash]

When done properly, your system will run continuously when the outdoor temp reaches the design temperature for your location. In doing so, it will maintain the indoor target temperature used in the manual J calculation.

Well maybe.

If the correct size is 31,000 btu total,and you select a nominal 3 ton system because a 2.5 is too small,there will be slight oversizing that will still cycle the system at the design temps.

[DavidNJ]

Well maybe.

If the correct size is 31,000 btu total,and you select a nominal 3 ton system because a 2.5 is too small,there will be slight oversizing that will still cycle the system at the design temps.


Unless it is VRV with at least one stage below the design point.

[dan sw fl]

So when you find one of these experts who run the Manual J and other calc. when selling you a system.

Is that going to size the unit so it will pull the temp down to a certain temp?

Does it try to size the unit so it will run most of the time during the heat of the day?

I have yet to find a person in Oklahoma that runs these calculation to find out how it does size the systems. I guess this is not only "No Mans Land " but not to many real " AC Men Either"

:CU:

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http://www.acca.org/store/product.php?pid=97

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