Smith XWH 150, Инструкция по эксплуатации

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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 Lead/Lag (see the XP Water Heater Service Handbook for an
explanation of the differential). The Leader will energize the lead
water heater on the Lead/Lag. For a new startup this will be the
Leader water heater.
Sequence of the Lead/Lag
To equalize the runtime of all water heaters on the Lead/Lag, the
firing sequence will automatically be changed at set intervals. For
the first 24 hours after initializing the Lead/Lag, 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:
Table 25. Sequence of the Lead/Lag
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.
Setpoint Adjustment operation with Lead/Lag
Setpoint Adjustment operation of the water heaters within the
Lead/Lag is available. Programming of the Setpoint Adjustment
will be done through the Leader water heater. Refer to the XP
Water Heater Service Handbook for information regarding
Setpoint Adjustment.
ACCESS MODES
User
The user can adjust tank target temperatures by touching the
MENU and accessing the Temperature Settings parameters on
the UIM. The date and time, and the temperature units can also
be changed.
Installer
Most parameters are available only to the installer, accessible by
entering the installer password, see the XP Water Heater Service
Handbook.
SAVING PARAMETERS
To save parameters and exit programming:
Press ACCEPT on the display after parameter settings.
To enter a parameter and continue programming:
Press ACCEPT after entering the values and return to the
parameter listings. Press BACK to return to the MENU listings.
See the XP Water Heater Service Handbook for a detailed
description of parameters and access modes.
High limit operations
The XP water heater is equipped with a fixed manual reset hight
limit and an adjustable manual reset high limit. The automatic
reset high limit has a set point of 200°F and the manual reset
high limit has a maximum set point of 210°F.
When the outlet temperature exceeds 200°F, the automatic high
limit action occurs. The water heater shuts down until the outlet
water temperature cools below 190°F, and a 60 second timer
has expired. If the outlet temperature continues to increase, the
manual reset high limit action will occur at 210°F.
High Limit Test procedure
1. Turn ON the main power to the water heater by placing the
ON/OFF switch in the ON position.
2. From the Touch Screen Display, access MENU to reach the
Temperatures parameters.
3. Select the Manual Reset High Limit parameter to access the
MIN & MAX settings..
4. Using the "-" button, decrease the set point of the MRHL
to below the current outlet temperature (or to its minimum
setting, whichever is higher).
5. Press the ACCEPT button to upload the new values to the
control.
6. If the current outlet temperature is above the new MRHL set
point, the MRHL will function causing water heater lockout. If
this occurs, skip to Step 9.
7. If the current outlet temperature is below the new MRHL place
the water heater into Service Mode. In Service Mode, the
water heater will fire at ignition speed and will then modulate
up to full fire.
8. Once the outlet temperature rises up to the MRHL set point,
the MRHL will function, causing the water heater to shut
down and lock out.
9. Repeat Steps 2 and 3.
10. Set the MRHL to the appropriate set point by using the "+" or
"-" buttons and then press ACCEPT..
11. Press the RESET button to clear the lockout.
12. If needed, exit Service Mode.
Low water cutoff protection
1. The Control Module uses temperature sensing of both
supply and return areas of the heat exchanger. If the flow
rate is too low or the outlet temperature too high, the control
module modulates and shuts the water heater down. This
ensures water heater shutdown in the event of low water or
low flow conditions.
2. Some codes and jurisdiction may accept these integral
features of the control in lieu of requiring an additional
limit control or low water cutoff. Consult local jurisdiction to
determine. A low water cutoff is available from the factory
(100173646).
LEAD/LAG
When multiple water heaters are installed, they can be wired
together in a Lead/Lag 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.