Crown TWZ065, Руководство по установке

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XII Operation
a. General Information
This boiler uses a proprietary version of the Honeywell L7248L Aquastat
®
cold start control used on boilers less tankless heater
or the L7224A Aquastat
®
warm start control used on boilers with tankless heater. to regulate water temperature and to manage
demands for up to two circulator zones.
Crown offers a low water cut-off kit that may be used with this control (PN 411000). Specific information on this kit, along with
installation and operating instructions, are available through Crown distributors and at www.crownboiler.com.
In accordance with the 2007 Energy and Independence Security Act, the L7248L cold start control first attempts to use residual
heat in the boiler to satisfy a space heating demand before firing the burner. In this manual, this function is referred to as a
“thermal purge”. For additional information see Part C of this section.
The L7224A warm start control is capable of thermal purge but it must be set by the installer. Note that using the thermal purge
on a warm start control may adversely affect the domestic hot water temperature in the tankless coil.
B. reading status and using Menu
The boiler’s status, as well as all parameters, are viewed and adjusted using the 3 digit LED and three buttons shown in Figure
12.0. The L7248L and L7224A have four basic modes of operation (also see Figure 12.1):
1. Status Mode - This is the default mode of operation for the control. In it, the display alternates between
StA
and a
number indicating the current status of the boiler. A list and description of these status numbers is shown in Table 12.2.
2. Operating Mode - Provides additional information about the current status of the boiler. Operating mode is entered by
pressing the I button shown in Figure 12.0. When this button is first pressed in Status mode, the display will alternately
display
bt
and the current boiler water temperature as shown in Figure 12.3. Pressing the I button again will display the next
line item shown in Table 12.2. In the same manner it is possible to advance through all of the “parameters” shown in Table
12.2. To return to Status mode, press I repeatedly until
StA
once again appears on the display. Alternatively, the control will
return to Status mode if no key is touched for 1 minute.
3. Error Mode - In Error mode, the control alternately displays
Err
and an error code. A list of these error codes is found on the
inside of the control cover, as well as in Section XIV of this manual (along with suggested corrective actions).
4. Adjustment Mode - Used to change parameters, such as high limit setting. See Part C for using Adjustment Mode.
FIGURE 12.0 LOCATION/APPEARANCE OF LED, BUTTONS