
Installation & Operation Manual
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Operating information
General
How the water heater operates
The Armor water heater uses an advanced stainless steel heat
exchanger and electronic control module that allows fully
condensing operation. The blower pulls in air and pushes flue
products out of the water heater through the heat exchanger
and flue piping. The control module regulates blower speed
to control the water heater firing rate. The gas valve senses the
amount of air flowing into the water heater and allows only the
right amount of gas to flow.
Control inputs and outputs
Tank thermostat / tank sensor
Either of these inputs will tell the water heater to provide heat
to the water tank. If a tank sensor is connected, the SMART
TOUCH control will ignore the tank thermostat.
0 - 10VDC input (set point or power)
The Armor water heater can be controlled by a Building
Management System (BMS) using a 0 - 10 VDC signal. The
control can be configured by the installer to use this signal to
either control set point or firing rate. This signal can be sent to
the heater through ModBus as well.
Temperature control
Modulation
The Armor water heater is capable of modulating its firing
rate from a minimum of 10% to a maximum of 100%. The
firing rate is dictated by the hot water draw and various other
temperature limitations.
Night setback
The controller may be programmed to reduce the DHW set
point during certain times each week. Seven different start and
stop times may be programmed for the DHW setback.
Flame current support
To prevent nuisance shutdowns when the water heater is firing
at minimum rates, the control will increase fan speed when the
flame signal drops too low.
Protection features
Outlet temperature, flue temperature, and temperature
rise limiting
The outlet temperature is monitored by the water heater outlet
temperature sensor. When the outlet temperature exceeds
185°F, the unit will reduce the fan speed. If the outlet water
temperature exceeds 195°F the control will shut the unit down
until it cools off.
The control module monitors the flue temperature by a sensor
located in the flue exhaust. If the flue temperature exceeds
215°F the control will reduce the maximum fan speed. If the
flue temperature exceeds 225°F (107°C) the control will shut
the unit down. The unit will restart automatically once the flue
temperature drops 10°F (6°C) and the minimum off time has
expired.
The control monitors the temperature difference between
the inlet and the outlet sensor. If the control determines the
temperature rise is too high, it will either reduce the firing rate
or shut down the unit as appropriate.
The unit will restart automatically once the temperature
difference has dropped below the allowable rise and the
minimum off time has expired.
Freeze protection
DO NOT install the water heater in a room likely to freeze.
⚠
DANGER
Freezing Conditions: If this appliance may
have been exposed to freezing conditions,
prevent from firing. Shut off power and
gas to the appliance immediately and
contact the factory for further instructions.
Allowing the appliance to fire when the
heat exchanger or near water heater piping
is frozen will result in death or serious
injury and significant property damage.
The following integral feature of the appliance control module
provides some protection for the appliance only -- not for the
system.
The water heater control module provides freeze-up
protection as follows:
•
Below an inlet temperature of 45°F (7°C), the water
heater pump operates constantly.
•
Below an inlet temperature of 37°F (3°C), the water
heater turns on.
• Water heater and pumps turn off if water inlet
temperature rises above 45°F (7°C).