Performance; Air Temperature And External Static Pressure Limits - Modine Manufacturing DFP Installation And Service Manual

PERFORMANCE

Table 16.1 - Air Temperature Rise - Power Vented Indoor Duct Furnaces ➀ ➁
Model Btu/Hr
Size Input Output
75 75,000 60,000
100,000 80,000
100
125 125,000 100,000
150,000 120,000
150
175,000 140,000
175
200 200,000 160,000
225 225,000 180,000
250 250,000 200,000
300,000 240,000 11111
300
350,000 280,000 11111➄
350
400,000 320,000 11111➄
400
➀
Ratings are shown for elevations up to 2000 feet. For higher elevations, the input rating should be reduced at the rate of 4% per 1000 feet elevation above sea level. For Canada, in
elevations between 2000 and 4500 feet, the unit must be derated to 90% of the rating listed above.
➁
Units approved for use in California by CEC.
➂
Power vented indoor duct furnaces are supplied with a factory installed air baffle. For applications where an air tempature rise less than 60°F is desired, it is recomended to remove
this baffle to reduce system pressure drop.
➃
For Variable Air Movement Applications, see page 13.
➄
The maximum CFM for the 350 and 400 results in a 23°F and a 27°F air temperature rise (respectively) based on the maximum unit pressure drop.

Air Temperature and External Static Pressure Limits

The maximum allowable discharge air temperature is 150°F. The maximum allowable air temperature rise for all Power Vented Units
is 100°F. All duct furnaces are designed for a maximum allowable static pressure of 3.0" W.C. on the heat exchanger.
Figure 16.1 - Recommended Unit Configurations
SINGLE TOP VIEW
2279 CFM
60°F ENTERING
AIR TEMP.
TANDEM TOP VIEW
160,000
2279 CFM
BTU/HR
20°F ENTERING
OUTPUT
AIR TEMP.
65°F
TEMP. RISE
PREHEAT
UNIT
16
20 ➂ 40 ➂ 50 ➂
60
Max
2778 1389 1111 926
3704 1852 1481 1235
4630 2315 1852 1543
5556 2778 2222 1852
6481 3241 2593 2160
7407 3704 2963 2469
8333 4167 3333 2778
9259 4630 3704 3086
5556 4444 3704
6481 5185 4321
7407 5926 4938
160,000
BTU/HR
125°F DISCHARGE
OUTPUT
AIR TEMP.
65°F
TEMP. RISE
160,000
BTU/HR
150°F DISCHARGE
OUTPUT
AIR TEMP.
65°F
TEMP. RISE
REHEAT
UNIT
Air Temperature Rise Through Unit (°F)
65 70 75 80
CFM
855 794 741 694
1140 1058 988 926
1425 1323 1235 1157
1709 1587 1481 1389
1994 1852 1728 1620
2279 2116 1975 1852
2564 2381 2222 2083
2849 2646 2469 2315
3419 3175 2963 2778
3989 3704 3457 3241
4558 4233 3951 3704
PARALLEL TOP VIEW
OUTPUT 65°F
TEMP. RISE
5698 CFM
20°F ENTERING
AIR TEMP.
OUTPUT 65°F
TEMP. RISE
5-564
85 90 95
654 617 585
871 823 780
1089 1029 975
1307 1235 1170
1525 1440 1365
1743 1646 1559
1961 1852 1754
2179 2058 1949
2614 2469 2339
3050 2881 2729
3486 3292 3119
200,000
BTU/HR
85°F DISCHARGE
SEE SERVICE
CLEARANCES AIR TEMP.
200,000
BTU/HR
100 ➃
Min
556
741
926
1111
1296
1481
1667
1852
2222
2593
2963