Cascade - Lochinvar 151 Installation & Operation Manual

11
Operating information

Cascade

When multiple water heaters are installed, they can be
wired together in a cascade sequence. A maximum of eight
water heaters 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. The Leader control can be programmed to use
Lead/Lag or Efficiency Optimization control methods.
Once the Leader water heater receives a call for heat from a
tank sensor, BMS or Modbus, the control will determine what
the set point will be. A fixed temperature set point can be
programmed into the control. See page 57 of this manual to
program the set point.
If the water temperature at the tank is less than the set point -
differential, then the control will initiate a call for heat on the
Cascade (see the Armor Water Heater Service Manual for an
explanation of the differential). The Leader will energize the
lead water heater on the Cascade. For a new startup this will
be the Leader water heater.
Sequence of the cascade
To equalize the runtime of all water heaters 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 M1-M2-M3-M4-M5-M6-M7-L
+ 2 hours M2-M3-M4-M5-M6-M7-L-M1
If a water heater locks out, it will automatically be given the
lowest priority for the rest of that 24 hour period.
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 water heater. Refer to the Armor
Water Heater Service manual for information regarding
Night Setback.
Installation & Operation Manual
(continued)
Access modes
User
The user can adjust tank target temperatures by pressing the
NAVIGATION dial when "SETPOINTS" is flashing at the
bottom of the display. The date and time, and the temperature
units can also be changed (see page 58).
Installer
Most parameters are available only to the installer, accessible
by entering the installer password, see the Armor Water Heater
Service Manual.
Saving parameters
the Armor Water Heater Service Manual)
Please note that the brackets ([]) denote
NOTICE
screen status.
To save parameters and exit programming:
Press the RIGHT SELECT [SAVE] key and then press the
RIGHT SELECT [HOME] key.
To enter a parameter and continue programming:
Press the RIGHT SELECT [SAVE] key 1 time to return to the
parameter listings; press again to return to the menu listings.
Remember to press the RIGHT SELECT [HOME] key when
finished programming in order to save the changes made.
See the Armor Water Heater Service Manual for a detailed
description of parameters and access modes.
(reference the Parameter Table in
61