Bosch W 125 T1 Operating & Maintenance Instructions page 7

TO TURN OFF GAS TO APPLIANCE
1. Close main manual gas valve and slide the gas valve
button to the OFF position.
PRESSURE REGULATION
The pressure regulator supplied with the water heater is
adjusted to operate on the gas specified on the rating plate
and:
- in Canada, is factory preset to deliver gas at the high
altitude pressure setting listed on the rating plate and as
shown below.
- in the U.S., is factory preset to deliver gas at the standard
altitude setting listed on the rating plate and as shown
below.
The pressure setting of the gas pressure regulator should
be checked at installation to assure that the setting is correct
for the gas being used and the altitude at which the
appliance is installed. See rating plate on the unit, or the
chart below for proper settings.
In Canada for a heater being installed at standard altitude
(0- 2.000 ft. elevation) the manifold pressure should be reset
at installation to value shown on the rating plate, or chart
below for standard altitude.
The gas pressures specified below refer to flow pressure
taken at the pressure tap in the gas inlet pipe (just above
pressure regulator, figure 5) while the heater is operating at
full input.
Appliance Regulator Pressure Setting
Type of Gas
kPa
natural 1.41
propone 2.61
natural 1.14
propane 2.09
Note: The high altitude ratings listed are Canadian Gas
Association high altitude ratings for the appliances and are
only valid in Canada. In the U.S. the National Fuel Gas Code,
ANSI Z 223.1/NFPA 54, recommends for high altitude
installations, above 2000 feet that the input rate be reduced
4% for each 1.000 feet above sea level.
PEEPHOLE
GAS VALVE BUTTON
PILOT IGNITOR BUTTON
WATER FLOW
SELECTOR
Pressure tap
Altitude
Inches, W.C.
standart
5.7
(0.2,000 ft.)
10.5
4.6
(2,000-4,500 ft.)
8.4
WATER TEMPERATURE CONTROL
To adjust water temperature use water flow selector, at
heater. For hot water rotate control Knob to the right.
Turn counter-
clockwise:
more water
- Warm
The control knob regulates the water temperature by ad-
justing the flow rate of the water through the heater:
- Maximum flow rate through the heater is 5L/min, (1.3
U.S. gal/min.) with temperature rise of 25°C (45°F) at
full input.
- Minimum flow rate through the heater is 2.3 L/min. (0.6
U.S. gal/min) with temperature rise of 55°C (99°F) at
full input.
For normal hot water use the control knob of water flow
selector should be turned clock wise (
remain in that position. This will permit control of remote
temperature by mixing more or less cold water with the hot
water supplied by the heater.
Note: If flow rate is adjusted to a point where water flow
through the heater is less than 2.3 L/min. the main
burner will shut-off. This is a safety feature.
Warning: Hot water can produce 3
in 6 seconds at 60°C (140°F)
In 30 seconds at 54°C (130°F)
HIGH TEMPERATURE LIMIT SWITCH
The BOSCH W125K...instantaneous gas water heater is
equipped with a high temperature unit switch with a set
point of 90°C (194°F). If the water temperature at the sensing
high bulb should exceed 90°C (194°F) the switch will open,
interrupting the safety circuit and stopping gas flow to the
pilot and main burner.
Pilot outage as a result of high limit operation indicates that
the heater is not functioning properly. The heater should be
checked by a qualified serviceman and the reason for
malfunction corrected. To relight pilot follow instructions
provided on the unit.
PRESSURE TAP
PRESSURE REGULATOR
MANUAL GAS VALVE
Turn
clockwise:
less water
- hot
) to stop and
rd
degree burns,
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