York D2NA060 User Manual
3. After maintenance of the pilot assembly, always measure
the resistance across the ignitor. If the resistance is greater
than 10 ohms, discard the ignitor and replace it with a new
ignitor.
than 10 ohms, discard the ignitor and replace it with a new
ignitor.
ADJUSTMENT OF TEMPERATURE RISE
The temperature rise (or temperature difference between the
return air and the heated air from the furnace) must lie within
the range shown on the rating plate and the data in Tables 2
and 3.
return air and the heated air from the furnace) must lie within
the range shown on the rating plate and the data in Tables 2
and 3.
After the temperature rise has been determined, the CFM can
be calculated as follows:
be calculated as follows:
After about 20 minutes of operation, determine the furnace
temperature rise. Take readings of both the return air and the
heated air in the ducts about six feet from the furnace where
they will not be affected by radiant heat. Increase the blower
CFM to decrease the temperature rise; decrease the blower
CFM to increase the rise.
temperature rise. Take readings of both the return air and the
heated air in the ducts about six feet from the furnace where
they will not be affected by radiant heat. Increase the blower
CFM to decrease the temperature rise; decrease the blower
CFM to increase the rise.
DIRECT DRIVE BLOWER
All units have direct drive multi-speed blower motors. Refer to
the unit wiring diagram and connect the blower motor for the
desired CFM.
the unit wiring diagram and connect the blower motor for the
desired CFM.
CHECKING GAS INPUT
NATURAL GAS
1. Turn off all other gas appliances connected to the gas meter.
2. With the furnace turned on, measure the time needed for one
revolution of the hand on the smallest dial on the meter. A typi-
cal gas meter usually has a 1/2 or a 1 cubic foot test dial.
cal gas meter usually has a 1/2 or a 1 cubic foot test dial.
3. Using the number of seconds for each revolution and the
size of the test dial increment, find the cubic feet of gas con-
sumed per hour from Table 9.
sumed per hour from Table 9.
If the actual input is not within 5% of the furnace rating with al-
lowance being made for the permissible range of the regulator
setting, replace the orifice spuds with spuds of the proper size.
lowance being made for the permissible range of the regulator
setting, replace the orifice spuds with spuds of the proper size.
NOTE: To find the BTU input, multiply the number of cubic feet of
gas consumed per hour by the BTU content of the gas in
your particular locality. (Contact your gas company for
this information since it varies widely from city to city.)
your particular locality. (Contact your gas company for
this information since it varies widely from city to city.)
SECURE OWNER'S APPROVAL
When the system is functioning properly, secure the owner's ap-
proval. Show him the location of all disconnect switches and the
thermostat. Teach him how to start and stop the unit and how to
adjust temperature settings within the limitations of the system.
Advise him that the flue exhaust hood surface and the immediate
area will experience high temperatures during the heating cycle.
All unauthorized personnel and debris must be kept away from
this area.
proval. Show him the location of all disconnect switches and the
thermostat. Teach him how to start and stop the unit and how to
adjust temperature settings within the limitations of the system.
Advise him that the flue exhaust hood surface and the immediate
area will experience high temperatures during the heating cycle.
All unauthorized personnel and debris must be kept away from
this area.
035-18265-001-A-0202
Unitary Products Group
11
°
F Temp. Rise =
BTUH Output
(OR) CFM =
BTUH Output
1.08 x CFM
1.08 x
°
F Temp. Rise
TABLE 9 - GAS RATE- CUBIC FEET PER HOUR
Seconds
for One
Rev.
Size of Test Dial
1/2 cu. ft.
1 cu. ft.
10
180
360
12
150
300
14
129
257
16
113
225
18
100
200
20
90
180
22
82
164
24
75
150
26
69
138
28
64
129
30
60
120
32
56
113
34
53
106
36
50
100
38
47
95
40
45
90
42
43
86
44
41
82
46
39
78
48
37
75
50
36
72
52
35
69
54
34
67
56
32
64
58
31
62
60
30
60
Example: By actual measurement, it takes 38 seconds for the hand on the 1-cubic foot dial to
make a revolution with just a 100,000 BTUH furnace running. Using this information, locate 38
seconds in the first column of Table 9. Read across to the column headed “1 Cubic Foot,”
where you will see that 95 cubic feet of gas per hour are consumed by the furnace at that rate.
Multiply 95 x 1050 (the BTU rating of the gas obtained from the local gas company). The result
is 99,750 BTUH, which is close to the100,000 BTUH rating of the furnace.
make a revolution with just a 100,000 BTUH furnace running. Using this information, locate 38
seconds in the first column of Table 9. Read across to the column headed “1 Cubic Foot,”
where you will see that 95 cubic feet of gas per hour are consumed by the furnace at that rate.
Multiply 95 x 1050 (the BTU rating of the gas obtained from the local gas company). The result
is 99,750 BTUH, which is close to the100,000 BTUH rating of the furnace.