Rinnai E75CN - Manual (Page 53)

Installation & Servicing Instructions Rinnai E-Series
53
12.4 Checking of the zero pressure control
The zero pressure control is set at the factory. To measure this value you need
a difference pressure gauge with a range of +0,2 to -0,8 mbar (+0.08 to -0.001”
W.C.). Follow the next procedure:
- Press the MODE-button for 5 seconds.
- The display will show COdE followed by an arbitrary number;
- Select by means of the or the button the code C123;
- Press the Store-button to confirm the code (code blinks 1 x);
- Press the MODE-button until SERV is shown;
- Press the STEP-button once until 1 is shown;
alternately 1 and OFF will be shown.
- Turn the upper measuring nipple on the gas valve open (fig. 19);
- Connect the hose of the digital pressure gauge to the upper measuring nipple of
the gas valve
- Press the button until the minimum value is achieved;
The fan will function to its minimum revolutions (burner is active)
- Measure the negative pressure.
Value should be 0 to -4Pa (0 to -0.04 mbar or 0 to -0.016" W.C.).
- If the zero pressure deviates too much:
- Remove black cover of the gas valve
- Remove cap with Torx screwdriver (fig. 20)
- Turn slightly the Torx screw behind the cap:
Turn left is positive pressure deviation
Turn right is negative pressure deviation
- Ending this procedure is done by pressing the Reset button.
- Proceed by checking the O
2
value and correct it if necessary.
Check point contamination
figure 19
Adjustment zero pressure
figure 20
NOTICE
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