Carrier 48HC*04–14 Service And Maintenance Instructions

46Table 19 – Altitude Compensation* (04--06) -- Low NOx UnitsNATURAL GAS ONLYNOMINAL HEAT INPUTELEVATION 60k BTUH 90k BTUH 120k BTUHFeet Meters OrificeSizeInput(btu/hr)OrificeSizeInput(btu/hr)OrificeSizeInput(btu/hr)0 --- 2000 0 --- 610 382 60,000 382 90,000 321 120,0002000 610 392 55,200 392 82,800 331 110,4003000 914 †40 52,800 †40 79,200 331 105,6004000 1219 †41 50,400 †41 75,600 351 100,8005000 1524 †41 48,000 †41 72,000 351 96,0006000 1829 †42 45,600 †42 68,400 361 91,2007000 2134 †42 43,200 †42 64,800 361 86,4008000 2438 †43 40,800 †43 61,200 372 81,6009000 2743 †43 38,400 †43 57,600 382 76,80010000 3048 442 36,000 442 54,000 †40 72,00011000 3353 442 33,600 442 50,400 †41 67,20012000 3658 452 31,200 452 46,800 †42 62,40013000 3962 473 28,800 473 43,200 †43 57,60014000 4267 483 26,400 483 39,600 †43 52,800* As the height above sea level increases, there is less oxygen per cubic ft. of air. Therefore, heat input rateshould be reduced at higher altitudes.{ Not included in kit. May be purchased separately through dealer.ORIFICEXX 1XX 2XX 3XX 4ACC. KIT PNCRLPELEV001A00CRLPELEV002A00CRLPELEV003A00CRLPELEV004A00Minimum heating entering air temperatureWhen operating on first stage heating, the minimumtemperature of air entering the dimpled heat exchanger is50_F continuous and 45_F intermittent for standard heatexchangers and 40_F continuous and 35_F intermittent forstainless steel heat exchangers. To operate at lowermixed--air temperatures, a field--supplied outdoor--airthermostat must be used to initiate both stages of heatwhen the temperature is below the minimum requiredtemperature to ensure full fire operation. Wire theoutdoor--air thermostat OALT (part no. HH22AG106) inseries with the second stage gas valve. See Fig. 59. Set theoutdoor--air thermostat at 35_F for stainless steel heatexchangers or 45_F for standard heat exchangers. Thistemperature setting will bring on the second stage of heatwhenever the ambient temperature is below the thermostatsetpoint. Indoor comfort may be compromised whenheating is initiated using low entering air temperatureswith insufficient heating temperature rise.LCTBW2ThermostatTH1TH2W1W1W2OALTC08442Fig. 59 -- OATL ConnectionsTroubleshooting Heating SystemRefer to Table 20 and Table 21 for additionaltroubleshooting topics.48HC