ACFT MAINT DEFICIENCY PROBLEM CREATES PRESSURIZATION PROBLEM FOR ACR LGT WHEN EQUIP COOLING OUTFLOW VALVE MALFUNCTIONS DUE TO IMPROPER INSTALLATION. ACFT EQUIP PROBLEM.

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DEPARTED DTW ENRTE TO MCO. CLBING THROUGH 23000 FT SO RPTED CABIN WAS CLBIG AT A RATE OF 500 FPM AND WAS UNABLE TO CTL IT WITH EITHER AUTO OR MANUAL CTLR. WHEN FIRST BROUGHT TO MY ATTN CAB IN ALT WAS APPROX 8000 FT. I INSTRUCTED FO TO FLY AIRPLANE AND SO AND I BEGAN TO WORK ON PROBLEM REFERENCING THE COCKPIT OPERATING MANUAL. COULD NOT STOP CABIN FROM CLBING. I TOLD SO TO CONTINUE TO TRY TO LOWER CABIN ALT AND WHEN CABIN REACHED 8500 FT TOOK COMMAND OF ACFT AND STARTED A NORMAL 3000-4000 FPM DSCNT. I INSTRUCTED THE FO TO ADVISE ATC WE WERE HAVING PRESSURIZATION PROBLEMS AND TO REQUEST A DSCNT TO 1000 FT. ONCE ATC CLRED US FOR LOWER I STARTED DOWN. AT ABOUT 20000 FT THE SO ADVISED ME THAT HE COULD NOW CTL THE CABIN ALT. AT 16000 FT I LEVELED OFF. THE CABIN ALT WAS AT 9000 FT AND DSNDING. I INSTRUCTED THE FO TO CALL DISPATCH AND I INFORMED ATC THAT WE COULD STAY AT 16000 FT WITH NO PROBLEM. WITH CABIN ALT UNDER CTL AND ALL ELSE NORMAL I INSTRUCTED THE FO TO FLY THE AIRPLANE AND I PROCEEDED TO WORK OUT MY OPTIONS WITH DISPATCH AND MAINT CTL. DISPATCH THOUGHT THAT WE COULD MAKE IT TO MCO WITH ADEQUATE FUEL RESERVES FROM OUR PRESENT POS. AFTER WORKING OUT THE TIME ENRTE AND FUEL BURN AT 16000 FT AND GETTING A GND SPD FROM ATC THE 3 OF US PLUS A JUMP SEAT RIDER; ALSO AN LGT CAPT; CAME TO THE CONCLUSION THAT YES; WE COULD MAKE MCO WITH BETTER THAN IFR RESERVES IN FUEL. WE PROCEEDED TO MCO ASKING ATC FOR AS DIRECT A RTE AS POSSIBLE. WE WERE ALSO ABOUT TO CLB UP TO 19000 FT TO FURTHER HELP OUR FUEL BURN. WE LANDED AT MCO WITH 9800 POUNDS OF FUEL (1 HR PLUS) AND WE WERE MET BY THE FAA. THAT IS WHY I AM FILING THIS RPT. AT NOT TIME DID WE DECLARE AN EMER. AT NO TIME DID THE CABIN PRESSURE EXCEED 9000 FT AND AT NO TIME DID WE GO BELOW OUR IFR FUEL RESERVES. DISPATCH WAS CONSULTED MANY TIMES ENRTE AND ALL AGREED THAT CONTINUING TO MCO WAS BEST COURSE OF ACTION. MCO MAINT FOUND AN EQUIP COOLING OUTFLOW VALVE INSTALLED IMPROPERLY AND WE FLEW SAME ACFT TO MSP WITH NO PROBLEM. SUPPLEMENTAL INFO FROM ACN 191995. IN CRUISE AT 16000 WE CONFERRED WITH COMPANY MAINT FOR SUGGESTIONS AND TO DETERMINE WHETHER THEY PREFERRED US TO RETURN TO DETROIT OR TO CONTINUE ON TO OUR DEST; ORLANDO; IF FUEL PERMITTED. SINCE THEY PREFERRED WE CONTINUED; WE CALLED OUR DISPATCH FOR PERMISSION AND FOR THEM TO RUN US A NEW FLT PLAN. DISPATCH CLRED US TO CONTINUE AS THEIR COMPUTATIONS SHOWED US ARRIVING AT MCO WITH OVER 7000 POUNDS. WE DID NOT DECLARE AN EMER NOR DID WE DECLARE MIN FUEL. WE DID NOT RECEIVE PRIORITY HANDLING; BUT WE DID REQUEST DIRECT ROUTINGS FROM ARTCC IN AN EFFORT TO CONSERVE FUEL. SUPPLEMENTAL INFO FROM ACN 191907. ON ARR AT MCO; WE WERE MET BY AN FAA REPRESENTATIVE; WHO RECORDED APPROPRIATE INFO ABOUT THE FLT. THERE WAS NO SPECIAL REASON AS FAR AS WE COULD DETERMINE; WHY WE WERE MET BY THE FAA.