No. 39 January 31, 1986 Subject: Periodic Testing of Check Valve Manifolds and Check Valves ‘Applicability: 4H5 Series — Check Valve Manifold (Vacuum System) 14H24 Series — Check Valve Manifold (Pressure System) 1H37 Series — Check Valve (Vacuum/Pressure System) Background: The above referenced components supplied by Airbome for use in aircraft pneumatic systems are manufactured with elastomeric components that deteriorate with age. As these components age, it is increasingly important to periodically assure their proper ‘operation, thus avoiding unscheduled system problems and aircraft downtime. All maintenance personne! should familiarize themselves with the pneumatic system ‘components listed above and perform both visual and operational checks to identify any deterioration in the performance of these components. Recommendation: It is recommended that beginning five years from date of manufacture, the serviceability of these components be verified every twelve months in accordance with the procedure provided on the applicable Airbome Technical Service Instruction. It is further recommended that these pneumatic system check valve manifolds and check valves be replaced ten years from date of manufacture. ‘The date of manufacture is encoded in the serial number located on the nameplate of these components. The numbers (1 through 12) of the serial number indicate the month (January through December) of manufacture. The following latter combinations of the serial number indicate the year of manufactu T= 1972 Bs 1980 M= 1984 AD= 1988 AH= 1992 V = 1973 C= 1977 H= 1981 AA= 1985 AE= 1989 AJ = 1003 We 1974 OD 1982 AB= 1986 AF = 1990 AK= 1994 = 1975 £ 1983 AC= 1987 AG= 1991 AL = 1995 For example, a serial number of “6K indicates a manufacture date of June, 1983. Technical Services Hotline: 1-800-382-8422 ‘Aerospace Parker Hannifin Corporation + Airborne Air & Fuel Products 711 Taylor Street + Elyria, Ohio 44035 + 216 284-6300 + Fax: 216 322-6094Airborne Air & Fuel Products Technical Service Instruction 4H24 SERIES — CHECK VALVE MANIFOLD (PRESSURE SYSTEM) The 1H24 series check valve manifold provides a means of coupling dual pressure sources. More importantly, the 1424 check valve manifold provides ‘a means of isolating these dual pressure sources in the event that one of the sources is not in operation. Operation ‘The “flapper-type” check valves are normally in the closed position. As airflow enters the manifold, the check valves open allowing airflow to the instruments. If airflow through a check valve Is stopped (i.e., pressure source taken out of operation), the check valve will close in order to allow the pneumatic system to properly function utilizing the lone operating pressure source. Troubleshooting Failure of one or both of the manifold's check valves to close would prevent isolation of the dual pressure sources in the event that one of the sources is taken out of operation. The elastomeric components utlized in the check valves deteriorate with age. Therefore, it is recommended that beginning five years from date of manufacture, the serviceability of the 1H24 series check valve manifold be verified every twelve ‘months. It is further recommended that this check valve manifold be replaced ten years from date of manufacture. The date of manufacture is encoded in the serial ‘number located on the nameplate of the check valve manifold. The numbers (1 through 12) in the serial number indicate the month (January through December) of manufacture. The following letter combinations in the serial number indicate the year of manufacture: Te1972 | 841976 ve1973 | 0-197 Fe1900 | Ma1984. | AD=1968 | AH=1902 He 1901 | AAet995 | AE=1989 1982 ‘Ade1993 Wet974) 0=1978 ‘AB1906 | AF=1990 | AKe1994 ‘Ant975 | 641979 | K=1903 | Ac-1987 | AG=1991 | AL=1995 Aerospace Parker Hannifin Corporation - Airborne Air & Fuel Products: 711 Taylor Street + Elyria, Ohio 44035 « 216 284-6300 + Fax: 216 322-6094Airborne Air & Fuel Products Technical Service Instruction 1H37 SERIES — Spring— CHECK VALVE <—— AirFlow Inlet Fitting Gasket Dise Discharge iting Check Valve Description ‘The 1H37 series check valve provides a means of Isolating dual air sources in the event that one of the sources is not in operation. Operation The “flappertype” check valve is spring loaded in the closed position. As airflow enters the valve, the check valve opens allowing airflow to continue through the system. if the airflow to the valve is stopped (ie., air source taken out of operation), the check vaive will close in order to allow the pneumatic system to property function utilizing the Jone operating air source. Troubleshooting Failure of the check valve to close would prevent isolation of the dual air sources in the event that one of the sources is taken out of operation. The elastomeric components utilized in the check valve deteriorate with age. Therefore, it is recom- mended that beginning five years from date of manufacture, the serviceability of the 1H37 series check valve be verified every twelve months. It is further recommended that this check valve be ‘eplaced ten years from date of manufacture. The date of manufacture is encoded in the serial number located on the nameplate of the chek valve. The numbers (1 through 12) in the serial number indicate the month (January through December) of manufacture. The following letter ‘combinations in the serial number indicate the year of manufacture: Ta1972 | B-1076 | Fa1980 | Mat084 | AD=1988 | AH=1992 vve1973 | c=1977 | He 1961] Adat985 | AE=1980| AJ=1999 we1974] D=1978 | Ja1982 | AB=1986 | AF=1990 AG=1991 | AL=1995 Ak=1094 ‘Aat975 | E=1979 | Ke1969 | ac=1967 ‘Aerospace Parker Hannifin Corporation - Airborne Air & Fuel Products 711 Taylor Street + Elyria, Ohio 44035 - 216 284-6300 + Fax: 216 322-6094Airborne Air & Fuel Products Technical Service Instruction 1H5 SERIES — CHECK VALVE MANIFOLD (VACUUM SYSTEM) oe wt iy = <— AirFiow = ‘Air Flow ——> ‘spring —! Description The 1H5 series check valve manifold provides a means of coupling dual vacuum sources. More importantly, the 1H5 check valve manifold provides ‘a means of isolating these dual vacuum sources in the event that one of the sources is not in operation. Operation ‘The “flapper-type” check valves are spring loaded in the closed position. As airflow is pulled through the manifold, the check valves open allowing airflow through the instruments, If airflow through a check valve Is stopped (.e., vacuum source taken out of operation), the check valve will close in order to allow the pneumatic system to properly function utilizing the lone operating vacuum source. Troubleshooting Failure of one or both of the manifold's check valves to close would prevent isolation of the dual vacuum ‘sources in the event that one of the sources is taken ‘out of operation. The elastomeric components utlized in the check valves deteriorate with age. Therefore, it is recommended that beginning five years from date of manufacture, the serviceability of the 1H5 series check valve manifold be verified every twelve months. It is further recommended that this check valve manifold be replaced ten years from date of manufacture. The date of manufacture is encoded in the serial ‘number located on the nameplate of the check valve manifold. The numbers (1 through 12) in the serial ‘number indicate the month (January through December) of manufacture. The following letter combinations in the serial number indicate the year of manufacture: Ta1972 | 841976 | F=19860 He 1961] AnHr1085 | AE=1969 Me1984 | AD=1988 | AH=1092 vet973 | Om1977 Ade1998 We1974) D=1978 Ani975 41962 | ABe1066 | AF=1990 | Aka1994 A0=1987 | AG=1991 Aerospace 41979 | Ket989 AL=1995 Parker Hannifin Corporation - Airborne Air & Fuel Products 711 Taylor Street + Elyria, Ohio 44035 + 216 284-6300 + Fax: 216 322-609410/27/00 Extended Airborne Date Code Listing RERBRRREEPRURRERERERER mITO OD? ectemwZEn—zo 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004