Carrier 48HC*04–14 - Natural Gas Only; Minimum Heating Entering Air Temperature; Troubleshooting Heating System

46
Table 19 – Altitude Compensation* (04--06) -- Low NOx Units
NATURAL GAS ONLY
NOMINAL HEAT INPUT
ELEVATION 60k BTUH 90k BTUH 120k BTUH
Feet Meters
Orifice
Size
Input
(btu/hr)
Orifice
Size
Input
(btu/hr)
Orifice
Size
Input
(btu/hr)
0 --- 2000 0 --- 6 1 0 38
2
60,000 38
2
90,000 32
1
120,000
2000 610 39
2
55,200 39
2
82,800 33
1
110,400
3000 914 †40 52,800 †40 79,200 33
1
105,600
4000 1219 †41 50,400 †41 75,600 35
1
100,800
5000 1524 †41 48,000 †41 72,000 35
1
96,000
6000 1829 †42 45,600 †42 68,400 36
1
91,200
7000 2134 †42 43,200 †42 64,800 36
1
86,400
8000 2438 †43 40,800 †43 61,200 37
2
81,600
9000 2743 †43 38,400 †43 57,600 38
2
76,800
10000 3048 44
2
36,000 44
2
54,000 †40 72,000
11000 3353 44
2
33,600 44
2
50,400 †41 67,200
12000 3658 45
2
31,200 45
2
46,800 †42 62,400
13000 3962 47
3
28,800 47
3
43,200 †43 57,600
14000 4267 48
3
26,400 48
3
39,600 †43 52,800
* As the height above sea level increases, there is less oxygen per cubic ft. of air. Therefore, heat input rate
should be reduced at higher altitudes.
{ Not included in kit. May be purchased separately through dealer.
ORIFICE
XX
1
XX
2
XX
3
XX
4
ACC. KIT PN
CRLPELE V001A00
CRLPELE V002A00
CRLPELE V003A00
CRLPELE V004A00
Minimum heating entering air temperature
When operating on first stage heating, the minimum
temperature of air entering the dimpled heat exchanger is
50_F continuous and 45_F intermittent for standard heat
exchangers and 40_F continuous and 35_F intermittent for
stainless steel heat exchangers. To operate at lower
mixed--air temperatures, a f ield--suppli ed outdoor --air
thermostat must be used to initiate both stages of heat
when the temperature is below the minimum required
temperature to ensure full fire operation. Wire the
outdoor--ai r thermostat OALT (part no. HH22AG106) in
series with the second stage gas valve. See Fig. 59. Set the
outdoor--ai r thermostat at 35_F for stainless steel heat
excha ngers or 45_F for standard heat exchangers. This
temperature setting will bring on the second stage of heat
whenever the ambient temperature is below the thermostat
setpoint. Indoor comfort may be compromised when
heating is initiated using low entering air temperatures
with insufficient heating temperature rise.
LCTB
W2
Thermostat
TH1
TH2
W1
W1
W2
OALT
C08442
Fig. 59 -- OATL Connections
Troubleshooting Heating System
Refer to Table 20 and Table 21 for additional
troubleshooting topics.
48HC