Boulter Buderus Benchmark 600 Series, Installation And Servicing Instruction

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Servicing 5
56 Installation and maintenance instructions for wall-mounted condensing gas boiler 600 - 28C • 01/2004
Subject to modifications resulting from technical improvements! Boulter Buderus Ltd. • http://www.boulter-boilers.com
5.3.10 Replacing the hot water out flow sensor and the
hot water heat retaining sensor.
z
Disconnect the system from the mains power supply.
z
Disconnect the plug of the hot water out flow sensor
(fig. 86, item 1) or the hot water heat retaining sensor
(fig. 86, item 2).
z
Turn on the hot water faucet and wait until the water flowing
out is cold.
z
Turn off the the hot water faucet.
z
Turn off the main DHW valve.
z
Remove the spring clip(s) (see frame 148).
z
Remove the sensor(s) and replace with new ones.
z
Connect the plugs.
z
Turn on a warm water faucet.
z
Open the main DHW valve and purge of air.
z
Turn the warm water faucet off.
z
Reconnect the system to the mains power supply.
5.3.11 Checking the hot surface ingnitor
z
Checking the hot surface ingnitor.
z
Disconnect the boiler from the mains power supply.
z
Disconnect the plug (fig. 87, item 1) of the hot surface
ignitor.
z
Set multimeter to measuring VAC.
z
Connect the boiler to the mains power supply and set in
service mode (see subsection 2.1.2).
z
Check if you measure 120 VAC when the code " 0C " is
visible in the display.
z
Disconnect the multimeter from the plug and set the
multimeter to measuring resistance.
z
Check if the resistance of the hot surface ingnitor is
between 50 -300
Ω
(see frame 165).
z
Disconnect the boiler from the mains power supply.
z
Reconnect the plug to the hot surface ignitor.
z
Reconnect the boiler to the mains power supply.
To check the connection lead to the UBA:
z
Disconnect the boiler from the mains power supply.
z
Remove the UBA 3 (see subsection 5.3.2).
z
Disconnect the plug of the hot surface ignitor (fig. 87,
item 1).
z
Measure the resistance of the cable (see fig. 88).
z
Reconnect the plug of the hot surface ignitor.
z
Remount the UBA 3 and connect the boiler to the mains
power supply.
fig. 86 Disconnect plugs of hot water sensors
1
2
fig. 87 Disconnect plug of hot surface ignitor
1
fig. 88 Measuring resistance of hot surface ignitor