Service Manual
1 Service (continued)
Cascade Screen:
The Cascade Screen provides the status of the cascade system. Items that can be viewed on the Cascade Screen are as follows:
Boiler Power Level Indicators - For each boiler present in the cascade a power level indicator will be present above its corresponding number. The level will rise and fall indicating the approximate power level of the boiler. The display box underneath each number will display “HW” when that boiler is providing heat for a Hot Water Generation call.
On Timer and Off Timer - The ON and OFF timers are used to force each boiler in the cascade to have a minimum on and off time to prevent short cycling.
Block Switch On Timer - Whenever a boiler is commanded to start, the block switch on timer is started. This provides a delay between the first ignition system and the second ignition system inside the boiler. Once the second ignition system is started, the timer is reset and the next boiler is prevented from starting until the timer times out. This process is repeated for each boiler in the cascade.
Demand - Shows the status of the cascade. Displayed items are:
No Demand - the Cascade leader has not received a system heat call.
SH Demand - the Cascade leader has received a system heat call.
Set Point Met - the system temperature has met the
User Set Point + the Off Differential.
Pump Delay - the cascade has satisfied a system heat call and the system pump is running for a fixed time.
System Temperature - This is the water temperature as measured by the system sensor located in the system supply piping.
SH Set Point - This is the set point of the cascade system. The boiler designated as the Leader will use this set point to determine the power level required to bring the system temperature to this point. A default value of 50°F (10°C) is displayed when the SH Call for Heat is inactive.
Time - The time is displayed in the upper
Status button - Pressing this button displays the Status Screen. This screens shows the current status of the SYNC boiler. Reference the Status Screen on page 13 for more information regarding this screen.
Main button - Pressing this button displays the Main Screen. From this screen, navigation to eight (8) other screens is possible. Reference the Main Screen on page 17 for more information regarding this screen.
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