(984) 0500-GB NOVA
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SERVO NOVA
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Gas accumulator (43)
Pressure in the gas accumulator can also be altered.
A reduction or increase of gas pressure in the accumulator depends upon the various soil
types.
• With very light soil the gas pressure can be somewhat reduced.
Important!
• No welding, soldering or mechanical work of any kind may be carried out on the
accumulator.
Altering pressure in the gas accumulator
This work must be carried out only by our Customer Service or by a specialist work shop.
A special filling and testing device is required to reduce or increase the preload pressure in the gas
accumulator.
1. Reduce pressure:
a) Remove plastic cap.
Remove the lead mould plug (if it exists) in the gas filling plug (44) with a pointed tool.
b) Slightly loosen the gas filling plug (44).
c) Screw on filling and testing device.
d) Slightly open the outlet valve on the filling device.
Slowly let the nitrogen out (N) until the mamometer shows the desired pressure has been
reached.
e) Close outlet valve, remove filling device, tighten gas filling plug and knock the lead mould plug
(if it exists) back in.
2. Increase pressure:
• Only use nitrogen (N) to fill the accumulator, do not use oxygen
(danger of explosion).
f) Connect filling device to nitrogen bottle.
g) Remove plastic cap.
Remove the lead mould plug (if it exists) in the gas filling plug (44) with a pointed tool.
Slightly loosen the gas filling plug (44).
Screw on filling and testing device.
h) Screw testing device onto nitrogen bottle.
i) Slightly open the outlet valve on the filling device and fill with nitrogen until the mamometer shows the required pressure has been
reached.
k) Close outlet valve, remove filling device, tighten gas filling plug and knock the lead mould plug (if it exists) back in.
Take note
All gas accumulators show a slight pressure drop after a certain period of time, according to "HYDAC" factory specifications.
The gas loss amounts to approx. 2-3 % pa.
It is recommended that the accumulator pressure be checked and, if necessary, regulated after 4-5 years.
