An apparatus for installing and removing a flow restrictor from a differential pressure measurement device, the differential pressure measurement device comprising a fitting connected in line with a fluid line, the fitting having a fitting opening for receiving the flow restrictor and a receptacle for retaining the flow restrictor, the apparatus comprising: a seal housing extending away from the fitting opening of the fitting, the seal housing being sealed to the fitting opening of the fitting, the seal housing having a housing opening spaced from the fitting opening of the fitting, and a channel connecting the housing opening to the fitting opening, a series of rotating drivers (26, 28, 30) being spaced along the channel, the rotating drivers (26, 28, 30) engaging the flow restrictor and moving the flow restrictor along the channel between the receptacle in the fitting and the housing opening of the seal housing; characterized in that: a first seal seals the fitting opening, a second seal is spaced from the first seal along the channel, and a third seal seals the housing opening, the distance between the second seal and the third seal being greater than the height of the flow restrictor in the direction of the channel that seals the housing opening, each of the first, second and third seals being selectively retractable between an extended, sealing position that seals and blocks the channel and a retracted, open position that unseals and unblocks the channel; a compartment is formed between the first seal and the second seal and another compartment is formed between the second seal and the third seal; and a first bleeder valve is positioned between the first and second seals and a second bleeder valve is positioned between the second and third seals, each of the first and the second bleeder valves being used to equalize the pressure between the channel and an exterior pressure in order to remove the risk of pressure leaking to the compartment formed between second seal and third seal. a seal housing extending away from the fitting opening of the fitting, the seal housing being sealed to the fitting opening of the fitting, the seal housing having a housing opening spaced from the fitting opening of the fitting, and a channel connecting the housing opening to the fitting opening, a series of rotating drivers (26, 28, 30) being spaced along the channel, the rotating drivers (26, 28, 30) engaging the flow restrictor and moving the flow restrictor along the channel between the receptacle in the fitting and the housing opening of the seal housing; characterized in that: a first seal seals the fitting opening, a second seal is spaced from the first seal along the channel, and a third seal seals the housing opening, the distance between the second seal and the third seal being greater than the height of the flow restrictor in the direction of the channel that seals the housing opening, each of the first, second and third seals being selectively retractable between an extended, sealing position that seals and blocks the channel and a retracted, open position that unseals and unblocks the channel; a compartment is formed between the first seal and the second seal and another compartment is formed between the second seal and the third seal; and a first bleeder valve is positioned between the first and second seals and a second bleeder valve is positioned between the second and third seals, each of the first and the second bleeder valves being used to equalize the pressure between the channel and an exterior pressure in order to remove the risk of pressure leaking to the compartment formed between second seal and third seal. a first seal seals the fitting opening, a second seal is spaced from the first seal along the channel, and a third seal seals the housing opening, the distance between the second seal and the third seal being greater than the height of the flow restrictor in the direction of the channel that seals the housing opening, each of the first, second and third seals being selectively retractable between an extended, sealing position that seals and blocks the channel and a retracted, open position that unseals and unblocks the channel; a compartment is formed between the first seal and the second seal and another compartment is formed between the second seal and the third seal; and a first bleeder valve is positioned between the first and second seals and a second bleeder valve is positioned between the second and third seals, each of the first and the second bleeder valves being used to equalize the pressure between the channel and an exterior pressure in order to remove the risk of pressure leaking to the compartment formed between second seal and third seal.