Burner Pressure Adjustment; Thermostat Calibration; Conversion To A Different; Type Of Gas - Bosch Pilot Ignition TF250 Series Installation Manual And Operating Instructions

Commissioning 16 litres appliances
Fig. 14 Inlet measurement test point
6.5

Burner pressure adjustment

▶ Loosen the burner test point captive screw ( Fig. 15,
[D]).
▶ Connect a manometer to the burner pressure measuring
point.
D
Fig. 15 Burner pressure test point
▶ Turn on gas to the appliance and relight the pilot.
▶ Turn on the water heater with full flow (16l/min).
▶ Using the appliance regulator, adjust the burner pressure
to the burner pressure figure on the data plate (table 10).
▶ Turn off water heater, remove manometer and tighten the
burner test point screw.
Max. Burner
TF400
Pressure (kPa)
Table 10 Burner pressure
16
9708069951-9.1V
Natural gas LP gas
0.71 kPa 2.4 kPa
6.6

Thermostat calibration

▶ Using a flow cup, adjust the flow rate using the hot tap (or if
using alternate method, use ball valve on outlet) to 6l/min.
▶ Allow unit to run for 1 minute and using a thermometer,
measure the hot water temperature. Required temperature
is 60 °C.
▶ To make adjustments, loosen the locking nut (fig. 16 [C])
and turn the thermostat adjustment nut (fig. 16 [D])
clockwise to decrease temperature, and anticlockwise to
increase, to achieve the required 60 °C.
▶ Reduce the water flow rate to 3l/min, allow the unit to run
for 1 minute, and ensure temperature does not rise above
63 °C. If it does, reduce temperature slightly by the
adjustment nut.
▶ Tighten the locking nut.
The recommended operating temperature is 55 °C.
▶ Open the tap fully, reduce and adjust the flow rate using the
water flow adjustment screw on the base of the water valve
1)
to achieve 55 °C.
▶ Check all gas points with soap solution.
Fig. 16 Thermostat adjustment
6.7 Conversion to a different type of gas
It is not recommended to convert these units to a different type
of gas.
1) 16l/min is based on a 25 °C temperature rise.
Pilot Ignition – 6 720 886 398 (2021/02)