Calibrating The Thermostat; Winterizing - Bosch GWH 1600 PS Owner's Manual

Operation instructions
4.4

Calibrating the thermostat

B If water temperature is too high or low, calibrate
thermostat.
B Remove front cover.
Caution: it should not be necessary to
loosen 22 mm nut beyond two turns out,
this is a gas seal and will leak if loosened
too far.
B Loosen the lock-nut collar above the 22 mm nut to
begin the calibration procedure. A seal of yellow
paint will be broken when it is loosened. See diagram
below.
Fig. 22
B Turning the 22 mm nut (upwards) will lower the flame
height. Loosening (downwards) will raise the flame
height. When making
recommended to have water flowing and the heater
on, then at 1/4 turn increments of the 22 mm nut, test
the temperature of the outlet water by measuring the
hot water temperature at an open tap.
Note: If the water temperature does not vary when the
thermostat is adjusted then it needs to be replaced.
Note: The thermostat's modulation will respond sooner
with varying flow rates of preheated water. Although
varying flows of cold water will be sensed by the
thermostat there will often be a delay to stabilize
temperature.
B Retighten lock-nut collar against 22 mm nut when
calibration is complete. Replace front cover panel.
16
LOCK-NUT COLLAR
22mm NUT
an adjustment it is
4.5

Winterizing

If there is a risk of freezing, proceed as follows:
B Remove both inlet and outlet elbow connections at
the rear of water valve.
B Remove the drain plug from the under side of the
water valve.
Fig. 23 Drain plug and filter location
1 Water valve
2 From heat exchanger
3 Slow ignition valve
4 To heat exchanger
5 Drain plug
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