DORCHESTER DR-FC 120, Installation, Comissioning And Maintenance Instructions

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Instruction manual DR-FC 35
is
3.10.6 Connecting an extra ON mode switch
External ON/OFF is an option for connecting an external ON/OFF switch. In
the OFF position, the programmed operating mode is active. In the ON
position, the programmed operating mode is overruled, and "ON mode" is
active.
1. Connect leads (X
3
and X
4
) to terminals 21 and 22 according to the
table (3.10.2 "Preparation") .
2. Fit the cable in the strain relief.
3. If you have no more connections to make:
- Fit the cover on the terminal block.
- Fit the covers onto the water heater.
3.10.7 Connecting extra error signal
The water heater has a terminal that is switched when an error
is detected.
This can be used to signal errors, for example with a lamp. A 230
V circuit
can be directly powered. Other voltages require a relay prescribed by
the
manufacturer.
1. Connect the live leads (X
1
and X
2
) to points 10 and 11 according to the
table (3.10.2 "Preparation") . If required, connect earth ( ) to
terminal 12.
2. Fit the cable in the strain relief.
3. If you have no more connections to make:
- Fit the cover on the terminal block.
- Fit the covers onto the water heater.
3.11 Checking supply
pressure, CO
2
value
and switching
pressure
Note
Before starting the water heater and/or checking the supply pressure and/or
the CO
2
value and/or the switching pressure, you should first fill (5 "Filling") the
water heater .
Caution
During commissioning or after conversion, you must always check the
supply pressure, the CO
2
value and the switching pressure.
Note
In order to check the supply pressure, the CO
2
value and the switching
pressure, you must have a CO
2
meter and a pressure gauge available.
3.11.1 Procedure for checking the supply pressure
To check the supply pressure, proceed as follows:
1. Isolate
(10.3 "Isolating the water heater from the mains") the water heater
from the power supply.
2. Carefully remove the covers from the water heater.
3. The electrical section is now visible.
4. The gas control valve has a test point that can be used for measuring the
supply pressure.
This test point has a sealing screw. Loosen the sealing screw by a few turns.
Do not completely loosen it; it can be difficult to re-tighten.
5. Open the gas supply and vent the gas supply line with the supply pressure
test point.
6. Connect a pressure gauge to the supply pressure test point as soon as gas
starts to flow from this test point.