Loss/Gain - Close or a Little Headroom?

[rufus]

I'll try to be direct -

Loss/Gain Calculation = 21633
Proposed Install = 21700

Does this seem close?
I was wondering if the L/G C should be matched with
equipment "on the money" or if a "little more headroom"
would be appropritate.

Just interested in a different opinion about how the
numbers add up with the equipment.

Thanks in advance.


Winter Outdoor Temp.: 1
Summer Outdoor Temp.: 95

Winter Indoor Design Temp: 70
Summer Indoor Design Temp: 72

Total Sensible Loss: 41659
Total Sensible Gain: 16641

Total Latent Loss: 0
Total Latent Gain: 21633

Total Btuh Gain: 2166
Capacity Multiplier: 1.00
A/C Unit BTUH Rating: 21633

Install Proposal List:
Trane XV80 80,000 BTU Model TUD080R9V3*
Trane Cased Coil Model RXC025S3HP
Trane XL 14i 2.0 Tons Model 4TTx4024*1000*

[furnace doctor]

Your Cooling gain is a total of Latent(moisture)heat and Sensible heat gains. Do you have Total Cooling Load?

[rufus]

There's isn't a 'Total Cooling Load' number
on the Trane contractors sheet.

Besides walls/windows/ceilings/floors/etc... L/G numbers,
there's a summary that reads:
Nominal A/C Unit Size - 2.0
Gas Furnace Output BTUH 41659
Electric Furnace KW 12.2

I'm wondering because other bids recommended
2.5 ton and 100K BTU.

The Trane 'Comfort Specialist' took window and sq.ft. measurments and the Software came up
a half ton and 20K BTU's less then my other three bids.

I'm going with the Trane System.

The other bid's have made me nervous that I may be
slightly undersizing.

Just looking for some feedback before install next Wednesday.

[dash]

One of the load calculations is wrong,it needs to be correct to be of any value.


Sensible 16thousand and latent 21000,sounds wrong,latent shouldn't be that high,check the numbers again.



Id think he means ,21000 is the total with the latent and sensible together,thus a ton ton system ,is what he selected.Where are you located and size and type onstruction would help?

[rufus]

Located in Bloomington (central) Illinois.
1980 Single story Ranch w/Basement.
Main: 1,400 sq. feet - 8 ft. ceilings.
Below Ground Basement: 530 sq. ft. - 7.5 ft. ceilings.
Basement already has 2 supplies;
Part of new install includes a return being added down there.

-8 36" x 54" single pane windows with storm windows.
4 facing south
3 facing east
1 facing north

Framing is 2x4 and R-11.
Original construction (Masonite) covered over with Vinyl siding.

Asphalt shingle roof with soffit vents & ridge vent.

Original Furnace: Rheem RGAA-100C
Original A/C: Rheem, exterior labels missing.
Original indoor coil: ? sealed in riveted sheet metal.

Is any of this helping or making sense?

Thanks.





-

[bornriding]

Personally, I like the little extra - I would go with 2.5 ton, myself. As the home and unit get older, they may not be as tight or efficient. In my experience, in a few years, 2 ton may not do the job.
And yet, it depends on whether comfort or efficiency is yur main concern. But if you want ther. set at 72 with 95 OAT, the extra surely wouldn't hurt.

Richard