Houston: 3.5 tons for 5,200 sq ft house?

[bbk]

Interesting.

That's gonna be a monstrous duck layout...does it have enough oompah to blow air out the last boot?

10' & 9' ceilings gonna take a lot of ceiling fans to bust up the stratification.

Kids ain't gonna leave the sliding glass patio doors open are they?

I'd like to see that built as spec'd and see how it works.

[uktra]

The other big question on the theoretical home is : are the ducts and air handler inside conditioned space? If they are, then a 3 ton will work fine. For all those like mrbillpro that don't think it will work, I suggest they visit some Building America homes in his area and talk to the customers that bought them. He also might want to read Home Energy magazine (july/August 05) just out, about a customer in West Columbia, Texas. People are becoming more educated through the internet and demand it be done right. The old "insufficient air movement" b.s. and "I have been doing it this way for 25 years" won't cut it anymore.

[Mr Bill]

Originally posted by uktra
Th For all those like mrbillpro that don't think it will work, I suggest they visit some Building America homes in his area and talk to the customers that bought them. He also might want to read Home Energy magazine (july/August 05) just out, about a customer in West Columbia, Texas.

I don't have read anything you install a 3.5 ton in Houston on 5200 sq .ft. and unless you building it in a cave you won't be comfortable, and I could care less what really anyone thinks I just want the address when you get er" done so I can go by and check out how happy the customer is, that is called proof the hell with all that manual J and D in Houston you will not be comfortable with a 3.5 ton on 5200 sq .ft. unless you have no glass and use R-600 insulation and your inside a cave I work around this everyday in Houston but hey you know better than me go for it!

[Panama]

Originally posted by uktra
The other big question on the theoretical home is : are the ducts and air handler inside conditioned space? If they are, then a 3 ton will work fine. ....

It was figured with attic ducts for the 2nd floor - R6.

[tuccillo]

Originally posted by Panama

Originally posted by uktra
The other big question on the theoretical home is : are the ducts and air handler inside conditioned space? If they are, then a 3 ton will work fine. ....

It was figured with attic ducts for the 2nd floor - R6.

Be aware that 3 tons nominal is probably really 2.5 tons at high outside temperatures ( when you need capacity the most ).

[Panama]

Originally posted by dash
When you size for 75° indoor,most "rating" need to be adjusted ,as they are the capacity at 80° indoors ,not 75° indoors ,this can easily be a 1/2 ton difference.

In my post above ,that's what I was refering to in #1.I thought Panama ,had made the adjustment,and selected a 3.5 ton based on the adjustment.

I don't think you'll find a 3 ton that will handle the load as stated.

[Edited by dash on 06-29-2005 at 03:38 PM]

Dash,

The "Lennox Engineering Data" I have has indoor DBs of 75 °F 80 °F, and 85 °F. Thus, no adjustments are needed.

[dash]

Originally posted by Panama

Originally posted by dash
When you size for 75° indoor,most "rating" need to be adjusted ,as they are the capacity at 80° indoors ,not 75° indoors ,this can easily be a 1/2 ton difference.

In my post above ,that's what I was refering to in #1.I thought Panama ,had made the adjustment,and selected a 3.5 ton based on the adjustment.

I don't think you'll find a 3 ton that will handle the load as stated.

[Edited by dash on 06-29-2005 at 03:38 PM]

Dash,

The "Lennox Engineering Data" I have has indoor DBs of 75 °F 80 °F, and 85 °F. Thus, no adjustments are needed.

Lennox should get a Gold Star, if the commonly provide the data needed that way,I wish they all did.Hoping ARI will start doing it.

[Freezeking2000]

A big problem i see is the fact that the air aroung a condenser gets about 10 degrees hotter than the ambient. So look at the numbers with 120 to 130 degree condensing temps for the outdoor unit and your 3 ton is not 2.5 tons.

[slice]

House built in Spring tx ( slighlty outside and north of houston) 3200 sq ft, single story insulated it with Icynene, (expanding foam insulation) Sealed the attic NO OUTSIDE AIR IN THERE, 3.5 tons maintains temp and 50% humidity, THis stuff is the up and coming thing,

[Panama]

Originally posted by tuccillo

Originally posted by Panama

Originally posted by uktra
The other big question on the theoretical home is : are the ducts and air handler inside conditioned space? If they are, then a 3 ton will work fine. ....

It was figured with attic ducts for the 2nd floor - R6.

Be aware that 3 tons nominal is probably really 2.5 tons at high outside temperatures ( when you need capacity the most ).

The engineering data shows about a 5% drop in total capacity when the outdoor DB rises from 95 °F to 105°F. Most of the drop is in latent capacity, and so the sensible capacity drops only about 3%. The increase in cooling load is far more pronounced -- about 25%.

[Mr Bill]

Slice:
House built in Spring tx ( slighlty outside and north of houston) 3200 sq ft, single story insulated it with Icynene, (expanding foam insulation) Sealed the attic NO OUTSIDE AIR IN THERE, 3.5 tons maintains temp and 50% humidity, THis stuff is the up and coming thing,


He is talking about 2000 sq. ft more than that with a 3.5 ton lots of difference there, as I said I will be here waiting let me know when you get that 3.5 ton on that 5200 sq.ft. home and I want to hear the customers feedback after a hot June like we have had were it's 100 and the humidity is 100% and he gets a couple high light bills because the unit will have to run 24/7.

[Panama]

[QUOTE]Originally posted by dash
[B]

Originally posted by Panama

Originally posted by dash
Dash,

The "Lennox Engineering Data" I have has indoor DBs of 75 °F 80 °F, and 85 °F. Thus, no adjustments are needed.

Lennox should get a Gold Star, if the commonly provide the data needed that way,I wish they all did. Hoping ARI will start doing it.

I think they all provide such data. I have some from Trane, and I think Goodman/Amana has it on their internet site.

I suspect Lennox provides it only to their dealers.

[Panama]

Originally posted by Freezeking2000
A big problem i see is the fact that the air aroung a condenser gets about 10 degrees hotter than the ambient. So look at the numbers with 120 to 130 degree condensing temps for the outdoor unit and your 3 ton is not 2.5 tons.

Those wonderful Texas alleys!