Carrier 50TJ016 Installation, Start-up And Service Instructions Manual

Also see for 50TJ016: Installation, Start-Up and Service Instructions Installation instructions

Contents

Base Unit OperationCOOLING, UNITS WITHOUT ECONOMIZER — Whenthermostat calls for cooling, terminals G and Y1 are ener-gized. The indoor (evaporator) fan contactor (IFC), and com-pressor contactor no. 1 (C1) are energized and evaporator-fan motor, compressor no. 1 and condenser fans start. Thecondenser-fan motors run continuously while unit is cool-ing. If the thermostat calls for a second stage of cooling byenergizing Y2, compressor contactor no. 2 (C2) is energizedand compressor no. 2 starts.HEATING, UNITS WITHOUT ECONOMIZER (If Acces-sory or Optional Heater is Installed) — Upon a call for heat-ing through terminal W1, IFC and heater contactor no. 1 (HC1)are energized. On units equipped for 2 stages of heat, whenadditional heat is needed, HC2 is energized through W2.COOLING, UNITS WITH ECONOMIZER — Upon a callfor cooling, when outdoor ambient temperature is above theoutdoor-air temperature control setting, the evaporator andcondenser fans and compressor energize. The economizerdamper moves to VENT position.Upon a first-stage call for cooling, when outdoor ambienttemperature is below the temperature control setting, the evapo-rator fan starts and economizer damper modulates to main-tain mixed-air temperature. The compressor(s) remains off.Upon a second-stage call for cooling, compressor no. 1 isenergized and mechanical cooling is integrated with econo-mizer cooling. Compressor no. 2 is locked out. If the outdoor-air temperature is below 50 F, a cooling lockout switch pre-vents the compressor(s) from running.When supply-air temperature drops below a fixed set point,the economizer damper modulates to maintain the tempera-ture at the fixed set point.FREEZE PROTECTION THERMOSTAT(S) — A freeze pro-tection thermostat (FPT) is located on the top and bottom ofthe evaporator coil. It detects frost build-up and turns off thecompressor, allowing the coil to clear. Once frost has melted,the compressor can be reenergized by resetting the compres-sor lockout.HEATING, UNITS WITH ECONOMIZER (If Accessoryor Optional Heater is Installed) — The outdoor air damperstays at VENT position while the evaporator fan is operat-ing. Upon a call for heating through terminal W1, the indoor(evaporator) fan contactor (IFC) and heater contactor no. 1(HC1) are energized. On units equipped for 2 stages of heat,when additional heat is needed, HC2 is energized throughW2.SERVICEBefore performing service or maintenance operations onunit, turn off main power switch to unit. Turn off ac-cessory heater power switch if applicable. Electrical shockcould cause personal injury.Cleaning — Inspect unit interior at beginning of each heat-ing and cooling season and as operating conditions require.Remove unit top panel and/or side panels for access to unitinterior.EVAPORATOR COIL — Clean as required with a commer-cial coil cleaner.NOTE: The 50TJ028 unit has a mist eliminator screen at-tached to the evaporator coil to prevent condensate runoff athigh wet-bulb conditions. Check periodically and clean asnecessary.CONDENSER COIL — Clean condenser coil annually andas required by location and outdoor-air conditions. Inspectcoil monthly — clean as required.CONDENSATE DRAIN — Check and clean each year atstart of cooling season.FILTERS — Clean or replace at start of each heating andcooling season, or more often if operating conditions re-quire. Refer to Table 1 for type and size.NOTE: The 50TJ028 unit requires industrial grade throw-away filters capable of withstanding face velocities up to625 fpm. Ensure that replacement filters for the 50TJ028 unitsare rated for 625 fpm.OUTDOOR-AIR INLET SCREENS — Clean screens withsteam or hot water and a mild detergent. Do not use throw-away filters in place of screens.LubricationCOMPRESSORS — Each compressor is charged with thecorrect amount of oil at the factory. Conventional white oil(Sontext 200LT) is used. White oil is compatible with 3GSoil, and 3GS oil may be used if the addition of oil is re-quired. See compressor nameplate for original oil charge. Acomplete recharge should be four ounces less than the origi-nal oil charge. When a compressor is exchanged in the fieldit is possible that a major portion of the oil from the replacedcompressor may still be in the system. While this will notaffect the reliability of the replacement compressor, the ex-tra oil will add rotor drag and increase power usage. To re-move this excess oil, an access valve may be added to thelower portion of the suction line at the inlet of the compres-sor. The compressor should then be run for 10 minutes, shutdown, and the access valve opened until no oil flows. Thisshould be repeated twice to make sure the proper oil levelhas been achieved.FAN SHAFT BEARINGS — For size 016 units, bearingsare permanently lubricated. No field lubrication is required.For size 020-028 units, the bearings are of the pillow blocktype and have grease fittings. The bearing opposite the mo-tor end has an extended tube line so it can be lubricated fromthe motor side. Lubricate the bearings twice annually.Typical lubricants are given below:MANUFACTURER LUBRICANTTexaco Regal AFB-2*Mobil Mobilplex EP No. 1Sunoco Prestige 42Texaco Multifak 2*Preferred lubricant because it contains rust and oxidation inhibitors.CONDENSER AND EVAPORATOR-FAN MOTOR BEAR-INGS — The condenser and evaporator-fan motors havepermanently-sealed bearings, so no field lubrication isnecessary.20