Lochinvar Armor X2 AWL1500, Руководство по установке и эксплуатации

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Operating information
High limit operations
When outlet temperature exceeds 200°F (93.3°C), high limit
action occurs. The appliance shuts down until the outlet water
cools down.
Flow sensing device
The SMART TOUCH control module uses temperature sensing
of both supply and return temperatures of the heat exchanger.
If the flow rate is too low or the outlet temperatures too high,
the control module modulates down and will shut the unit
off. This ensures appliance shutdown in the event of low flow
conditions.
Flow switch
Two flow switches are installed in the outlet manifold. These
swiches ensure there is sufficient water flow prior to firing the
burner.
Cascade
When multiple units are installed, they can be wired together
in a cascade sequence. A maximum of eight appliances can be
controlled from a single control. In this application one water
heater would be designated as the Leader control and all others
would be designated as Member controls.
Once the Leader receives a call for heat from the Enable, 0 - 10
VDC input, or ModBus, the control will determine what the set
point will be. A fixed temperature set point can be programmed
into the control.
If the water temperature at the tank sensor is less than the set
point - the off-on differential, then the control will initiate a call
for heat on the Cascade (see the Armor X2 Service Manual for
an explanation of the offset and differential). The Leader will
energize the lead water heater on the Cascade. For a new startup
this will be the Leader.
The water heater will fire at its ignition speed and will then
modulate its firing rate to maintain the set point. If the first
water heater reaches 100% of its firing rate, the Leader will
calculate at what point the second appliance could fire at 10%
of its firing rate. At this point, the Leader will fire the second
appliance on the Cascade. For a new startup, this would be the
first Member appliance. The water heater will fire at its ignition
speed and will then modulate its firing rate to maintain the set
point.
Installation & Operation Manual
Sequence of the cascade
To equalize the run time of all appliances on the Cascade, the
firing sequence will automatically be changed at set intervals.
For the first 24 hours after initializing the Cascade, the
sequence will be changed every hour. After that the sequence
will be changed once every 24 hours. The switching on/off
sequence will be as follows:
TIME SWITCHING ON SEQUENCE
Start L-M1-M2-M3-M4-M5-M6-M7
+ 1 hour M2-M3-M4-M5-M6-M7-L-M1
+ 2 hours M4-M5-M6-M7-L-M1-M2-M3
If the set point still cannot be met, the Leader will continue
firing more Members until either the heat demand is met or all
units on the Cascade are firing. As the heat demand decreases,
the last appliance on will modulate down to 10% of its firing
rate. Once the demand for that water heater is zero, it will
shut down. As the heat demand decreases further, the second
to last water heater will modulate down and shut off. This
will continue until the demand is satisfied and all appliances
are shut off.
A BMS can also control the firing rate of the Cascade directly
through the 0 - 10V BMS input or through ModBus.
Night Setback operation with cascade
Night Setback operation of the water heaters within the
Cascade is available. Programming of the Night Setback will
be done through the Leader. Refer to the Armor X2 Service
Manual for information regarding Night Setback.