Checking The Gas Leakage Monitoring (Vps) - DeDietrich C 340 Series Installation And User Manual

Fig.115 Negative (-) side of the air pressure
differential switch
12
(+)
14
X mbar
Fig.116 Preparing the gas circuit
4
3
P1
Fig.117 Connecting a hose
3
5
7
7762666 - v.02 - 29092020
10. Remove the syringe hose from the + side of the air pressure
11. Disconnect the silicon hose from the - side (P2) of the air pressure
12. Connect the - side of the air pressure differential switch the hose
13. Pull out the syringe very slowly until error code E.04.08 appears on
10
P (-)
14. Check the pressure indicated by the pressure gauge at that point. This
2
11
P (+)
1
13
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11.3.8
The VPS check consists of two actions: checking the VPS for leaks and
checking the switch value. Proceed as follows:
1. Switch off the boiler.
2. Close the boiler gas valve.
3. Remove the pressure from the gas pipe by unscrewing the screw in
2
4. As soon as the gas pipe is pressure-free, re-tighten the screw.
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5. Open the screw at measuring point 3 on the gas control valve.
6. Connect a hose to measuring point 3 of the gas valve.
5
2 P
3
6
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differential switch and reconnect the original hose.
differential switch.
coming from the T piece.
the display.
is the switch pressure.
A switch pressure between -5.5 and -6.5 mbar is good. A lower or
higher switch pressure indicates a problem with the air pressure
differential switch.

Checking the gas leakage monitoring (VPS)

measuring point P1.
11 Maintenance
C 340 / C 640 151