10902 17TH PL W 2025-01-06 - Laserfiche WebLink

• If pressure rises above 2000 microns, a leak is present. It must be noted that many field variations exist that may Check for leaks as previously indicated and repair as effect the operating temperature and pressure readings of a necessary then repeat evacuation. heat pump system. It should also be noted that all Goodman' Heat Pump System Start Up Systems utilize fixed orifice refrigerant control devices.As such, When opening valves with retainers, open each valve only the following procedures have been developed for this type of until the top of the stem is 1/8"from the retainer.To avoid loss refrigerant control device. of refrigerant, DO NOT apply pressure to the retainer.When I. DETERMINATION OF INDOOR AIR FLOW (L/S) AND opening valves without a retainer remove service valve cap HEATING CAPACITY (KW) and insert a hex wrench into the valve stem and back out the Prior to using the methods described below to check the stem by turning the hex wrench counterclockwise. Open the valve until it contacts the rolled lip of the valve body. NOTE: system's charge it is important to verify that the system is These are not back-seating valves. It is not necessary to delivering sufficient air across the indoor coil (L/s, liters per force the stem tightly against the rolled lip. Open the suction second),as well as,the operating capacity of the system.The following procedures are suggested methods for determin- service valve first! If the liquid service valve is opened first,oil from the compressor may be drawn into the indoor coil TXV, ing the system air flow(L/s)and its operating capacity(kW). restricting refrigerant flow and affecting operation of the Airflow Test Instruments - There are a number of readily system.After the refrigerant charge has bled into the system, available instruments which can be used in the field for airflow open the liquid service valve. The service valve cap is the determination such as Barometers, Volume-Aire Air Balanc- secondary seal for the valves and must be properly tightened ers, Anemometers, and Velometers. When using these de- to prevent leaks.Make sure cap is clean and apply refrigerant vices it is important to follow the manufacture's instructions oil to threads and sealing surface on inside of cap. Tighten provided with them. cap finger-tight and then tighten additional 1/6 of a turn (1 wrench flat),or to the following specification,to properly seat Airflow Determination - Indoor Coil the sealing surfaces. The heat pump system has been designed for optimum perfor- 1. 3/8" valve to 5 - 10 in-Ibs (0.56-1.30 Nm) mance with the airflow across the indoor coil equaling 2. 5/8" valve to 5 -20 in-Ibs (0.56-2.26 Nm) approximately 190 L/s per TON. 3. 3/4" valve to 5 -20 in-Ibs (0.56-2.26 Nm) e.g. 4. 7/8" valve to 5 -20 in-Ibs (0.56-2.26 Nm) A 2 TON system should have 2 x 190 = 380 L/s. Do not introduce liquid refrigerant from the cylinder into the Temperature Rise Method-Although not as accurate as the crankcase of the compressor as this may damage the com- use of test equipment, a method of determining the indoor pressor. airflow in a system employing electric resistance heat as the backup heat source is by the temperature rise method and is 1. Purge gauge lines after attaching to the service valves. calculated using the following formula: 2. Determine the proper charge from the serial data plate. Charge includes the evaporator coil and 7.6 m of line set. 828.3 x Input Power (kW) Systems having more than 7.6 m of interconnecting tubing Air Flow (L/s) _ require an additional charge allowance of 6 oz. Temperature Rise (°C) 3. Break the vacuum by opening the suction and liquid valves on the gauge set and weighing in the calculated where charge. measured input voltage (Volt) x current (Amp) 4. Set thermostat to call for cooling. Check indoor and kW _ outdoor fan operation and allow system to stabilize for 10 1000 minutes for fixed orifices and 20 minutes for expansion e.g. valves. input voltage = 230 Volt, measured current 35 amps FINAL CHARGE ADJUSTMENT temperature rise = 12°C The outdoor temperature must be 60OF (16°C) or higher. air flow = 828.3 * 230 * 35/ 1000/ 12 Set the room thermostat to COOL, fan switch to AUTO, = 556 (L/s) and set the temperature control well below room tempera- ture. After system has stabilized per startup instructions, NOTE:The compressor circuit(outdoor unit)mustbe off check superheat as detailed in the following section. to insure that the Temperature Rise measured across the indoor unit is due only to the electric heat. GENERAL: The following information has been developed to assist the service technician in determining the proper charge for Goodman° Heat Pump Systems. 5 Downloaded from www.Manualslib.com manuals search engine