Camus Hydronics DRW1000, Installation And Service Manual

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inlet or at the flue discharge. A minimum differential pressure
across the sensing points of the pressure switch proves
operation of the combustion air fan. This is set in the factory and
may be adjusted for field conditions. The diagnostics display will
exhibit a status of an open Interrupted Air Switch (ILK Off) when
the differential pressure switch detects a sustained low air
condition. This condition could be caused by a number of factors
including:
• Sensing line broken or loose fitting.
•
Dirty filter or blocked vent.
• Steady high wind condition exceeding 40 MPH.
• Incorrectly set switch.
•
Missing bleed restrictor on total pressure side air line.
5.4 BLOCKED FLUE SWITCH
All models use a normally closed blocked flue switch to shut
down the appliance under the following conditions:
1) Air intake 50% blocked
2) Vent outlet 80% blocked
5.5 DIFFERENTIAL GAS AND LOW GAS PRESSURE
SWITCHES
A manual reset differential gas pressure switch is standard on
DR3000 – 5000 and available as an option on DR300 - 2500. If
differential gas pressure exceeds the maximum setting of the
pressure switch, the appliance will shut down and an open gas
pressure switch will be shown on the display. A low gas pressure
switch is standard and monitors the minimum incoming gas
supply pressure supplied to the gas train. If gas pressure falls
below the minimum setting of the pressure switch, the appliance
will shut down and an open gas pressure switch will be shown
on the display.
5.6 HIGH LIMIT
A high limit aqua-stat control is located at the back of the
appliance and the control bulb is installed in a dry well in the
heat exchanger header outlet. The setting of this control limits
maximum discharge water temperature. A manual reset high
limit will have a red reset button which must be pushed
whenever water temperature has exceeded the set point of the
manual reset limit. The temperature of the water in the heat
exchanger must drop a minimum of 15°F (8.3°C) below the
setting of the high limit control before the reset function can be
activated. Whenever an appliance is supplied with both an auto
reset and manual reset high limit always set the auto reset limit
10 ºF (5.5°C) below the manual reset limit to prevent nuisance
tripping
5.7 DYNAFORCE® SOLA
DR300 – DR2500 models utilize a hot surface ignition system.
DR3000 – DR5000 models utilize a proven pilot. The ignition
control proves the presence of the flame using a flame
rectification voltage (0.8Vdc), energizes the main gas valve,
proves the presence of main burner flame, and provides for
lockouts. The Alarm light will be lit on the ignition control module
in the event of a fault.
Figure 21: Ignition Module
5.7.1 SERVICE PARTS
The electronic ignition module is not repairable. Any
modification or repairs will invalidate the warranty and may
create hazardous conditions that result in property damage,
personal injury, fire, explosion and/or toxic gases. A faulty hot
surface igniter or ignition module MUST BE replaced with a new
factory approved unit only. A factory approved igniter, ignition
control module and flame sensor for this specific unit is available
from your local distributor. DO NOT use general purpose field
replacement ignition modules, igniters or sensors. Each
appliance has one ignition module, one hot surface igniter and
one flame sensor.
5.7.2 IGNITION MODULE LOCKOUT FUNCTIONS
The ignition module may lockout in either a hard lockout
condition requiring pushing of the reset button to recycle the
control for a CSD1 requirement or a soft lockout condition which
may be reset automatically once the error clears. A typical hard
lockout fault can occur with single a trial for ignition CSD1
module. Pushing the reset button on the ignition control is the
only way to reset an ignition module that is in a hard lockout
condition. The reset button is located on the ignition module.
Turning the main power “OFF” and then “ON” or cycling the
thermostat will not reset a hard lockout condition. Wait until the
display shows the temperatures on screen before pushing the
reset button when the ignition module is in a hard lockout.
The Dynaforce® Controller will go into an alert condition, for
example, if the supply sensor is disconnected, flow switch, or air
switch are not made. If the fault is not corrected, the boiler will
stay in an alert condition. Once the fault is corrected, the boiler
will automatically return to normal operating state.
5.8 DYNAFORCE® CONTROLLER
Table 11: Connector Description
Connector Connector Description
J1
Flame Sensor, Ground Rod
J2 Fan Modulation (DR300 – 1000)
J3
Display, Lead lag, Modbus Comm.
J4
24VAC Power, Pump, VFD
J5
Gas Valve, Safety Interlock String
J6 Safety Annunciation, Remote Operator
J8
24VAC Power, Inlet, Outlet Sensor
J9
DHW, Stack Sensor