Service manual

15
8 INSTRUMENTATION AND
CONTROLS
8.1 SAFETY CONTROLS
High Temperature Limit
The high temperature limit is located behind the
appliance’s access doors. A remote capillary
bulb runs to a thermo-well on the outlet side of
the inlet/outlet header. The appliance high limit
is set at the factory to 210ºF for hot water and
230ºF for heating.
Air Proving Switch
An air proving switch is provided on each burner
to prove the operation of the fan and adequate
air flow to the burner. The pressure switch
sensing point is at the air box below the
combustion chamber. The LED indicator for air
flow will not illuminate should the pressure
switch detect a sustained low air condition.
Blocked Flue Switch
A normally-closed blocked flue switch is
provided for the boiler. It senses a blocked flue
condition or a blocked fan inlet and shuts down
the boiler.
8.2 CONTROL PANEL
The appliance is provided with a control panel at
the front. Operating controls are installed inside
the control box and are accessible by undoing
the thumb screw and opening the door. The
diagnostic information centre as well as the
on/off switch, 24V fuse, and the appliance
temperature controls reside on the control panel
door.
Figure 14: Display, Appliance Temperature
Controller and Indicating LED
The Boiler Temperature Controller (BTC 1) for
this appliance is a Camus 78-0017 SmartFlame
control. The BTC 1 uses a Liquid Crystal Display
(LCD) as a method of displaying boiler
information. The BTC 1 is used to setup and
monitor the operation of the system. The BTC 1
uses three push buttons for selecting and
adjusting settings.
Boiler Temperature Controller Features:
It initiates the local call for heat and sets the
target inlet (appliance inlet) water temperature.
This controller accommodates heating and
domestic hot water control with multiple modes
of operation which provide set point as well as
reset control. It provides the following:
• Readings of inlet and outlet temperatures
and ∆T temperature rise
• Operation as an auto reset limit.
• Operation as a control for inlet water
temperature.
• Optional tank mounted sensor used in
conjunction with inlet sensor.
• Adjustable pump delay feature based on
∆T temperature difference between inlet
and outlet temperatures. Accepts 1/6
hp. pump directly across terminals 13 &
14.
• Adjustable; target temp
• Display of run hours for maintenance
purposes. Counter displays up to
999,999 hours.
• Flame failure signal 24 V.
• Molex connector for ease of service.
• Error message display.
• Test override feature to test pump
operation and alarm.
• Pump exercising feature runs pump 10
seconds every three days of no pump
operation.
The menu structure for the Appliance
Temperature Control was designed to be
intuitive and easy to use for a first time user. To
maintain the MicoFlame Modulating boiler at its
correct settings two levels of access is provided,
User and Installer with an increasing amount of
parameters that can be adjusted by the Installer.
This is done to provide an easy means of
communication for the end user and a more
indepth approach for factory installers when
installing and troubleshooting.