Camus Hydronics ADVANTUS AVH 500, Installation, Operation And Service Manual

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5.4 BLOCKED FLUE SWITCH
All models use a normally closed automatic reset blocked flue switch to shut down the appliance under the following conditions:
1. Air intake 50% blocked
2. Vent outlet 80% blocked
When the blocked flue switch has tripped check the venting and/or air intake piping for obstructions before placing the unit into operation.
Power must be shut off to the boiler and gas supply to the appliance must be closed before attempting to investigate reason for blocked
flue condition. If the boiler cannot be restored to normal operating condition after removal of obstruction, please contact a qualified service
agency.
Figure 26: Blocked Flue Switch
5.5 HIGH AND LOW GAS PRESSURE SWITCHES
A manual reset high gas pressure switch is standard on AV3000-4000 models and available as an option on AV500-2500 models. If 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 Aquastat 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°F
(5.5°C) below the manual reset limit to prevent nuisance tripping.
5.7 Advantus SOLA
AV500-AV2500 models utilize a
Hot Surface ignition system. AV3000-AV4000 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 27: Ignition Module