High Pressure Pump Servicing Instructions – Page 13
Note that the VS100 relief valve is installed upside down on the Mk1 Electric PSU with the WM pump.
Directions here are given as if you are looking at the end hexagonal adjustment cap.
Once you have replaced the relief valve, and before replacing the plastic case of your PSU, reconnect the
particle filter housing so that you can perform the following steps.
1.
Loosen the locking nut underneath the large
hexagonal part of the relief valve.
2.
Place the pickup hose into a water source and connect
the RO unit as during normal operation.
3.
With the pressure control valve on the RO system fully
open (counter-clockwise), run the PSU until only clear
bubble free water comes out brine hose.
4.
Turn the pressure control valve clockwise until it is
fully closed whilst watching the pressure on the gauge.
New relief valves from the factory are typically pre-set
to a low pressure, so you should be able to close the
valve fully before the pressure reaches 55 bar (800
psi). If the pressure reaches 55 bar (800 psi) before the
valve is fully clockwise, then the relief valve is already
set too high. In this case, turn the hexagonal part of
the relief valve anti-clockwise three times and go back
to step 3.
5.
With the PSU running and the pressure control valve
fully closed (clockwise), turn the adjustment cap on
the relief valve clockwise until the pressure gauge
reaches 55 bar (800 psi).
6.
Fully open the pressure control valve on the RO unit
(anticlockwise) and turn off the PSU.
7.
Turn the adjustment cap on the relief valve clockwise
one complete turn (360°).
8.
The relief valve is now set correctly to 69 bar (1000
psi). Lock the adjustment cap using the locking nut or
some other thread locker e.g. Loctite or similar.
