Thermo Scientific 450iQ Instruction Manual page 241

Servicing
Mode Valve Replacement
Equipment Damage Do not disconnect the plumbing from the valve end.
Disconnect from the attaching end only. This will prevent damaging and
leaks from the valve end.
L
Figure 7–52. Removing and Replacing the Mode Valve pt 2
4. Replace the mode valve and assemble in reverse order.
7-47
Thermo Scientific 450iQ Instruction Manual