Installation & Operation Manual
7 Operating information (continued)
Cascade
When multiple appliances 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 appliance would be designated as the Leader control and all others would be designated as Member controls. The set point or firing rate can be controlled by the 0 - 10V input as well.
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.
Once the Leader appliance receives a call for heat from a BMS, or external thermostat, the control will determine what the set point will be. A fixed temperature set point can be programmed into the control. See
If the pool water temperature is less than the set point - the off differential, then the control will initiate a call for heat on the Cascade.
The appliance will fire and will then stage its firing rate to maintain the set point. If the first appliance reaches 100% of its firing rate, the Leader will calculate at what point the second appliance could fire at its minimum 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 appliance will fire and will then stage its firing rate to maintain the set point.
If the set point still cannot be met, the Leader will continue firing more Members until either the heat demand is met or all appliances on the Cascade are firing. As the heat demand decreases, the last appliance on will stage down to its minimum firing rate. Once the demand for that appliance is 0% it will shut down. As the heat demand decreases further, the second to last appliance will stage down and shut off. This will continue until the demand is satisfied and all appliances are shut off.
DAY | SWITCHING ON SEQUENCE |
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Start | |
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+ 1 hour | |
+ 2 hour | |
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Night Setback operation of the pool heater within the Cascade is available. Programming of the Space Heating (SH) Night Setback will be done through the Leader heater. Refer to the
Ramp Delay operation of the pool heaters as described in the
Night setback
The controller may be programmed to reduce the pool water heating during a certain time each day. A start and stop time can be programmed for each day of the week.
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