Crestron electronic 1.5 Benutzerhandbuch

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Installation & Operation Manual
10  
Operating information   
Monitor external limits
Connections are provided on the connection board for 
external limits such as an additional high limit.  The 
SMART TOUCH control will shut off the burner and 
inhibit relighting whenever any of these external limits 
open.
Run-time and alarm outputs
The boiler provides dry contacts for indicating when the 
boiler is running, and when it is unable to operate.
Run-time and cycle counting
The control uses four timers to monitor the total hours of 
burner operation:
75 - 100% 
 
50 - 75%
25 - 50% 
 
<25%
The control uses four (4) ignition counters to monitor 
the amount of boiler cycles.  The first counter counts all 
ignitions of the control.  The second counter counts only 
ignition attempts that have failed.  The third and fourth 
counters are the same as the first and second respectively, 
but can be reset by the installer.
Service reminder
The control can be programmed for service reminder 
notification.  This notification will become active when 
either a set amount of time has expired, or a set amount of 
running hours or cycles has expired (all adjustable by the 
installer).  The service reminder notification can be reset 
by the installer.  The service company’s name and phone 
number can be programmed to display when service is due.
Error logging
The control will hold in memory the last 10 blocking faults 
as well as the last 10 lockout faults.  The date and time of 
the occurrence will be recorded as well.  Only the 10 most 
recent occurrences will be held in memory.
Boiler temperature regulation
Operating temperature (target)
The SMART TOUCH control module senses water 
temperature and regulates boiler firing and firing rate to 
achieve a target temperature.  The target temperature can 
be set between 32°F (0°C) and 185°F (85°C).
•   Target temperature is fixed when the outdoor 
 
sensor is not installed.
•   Target temperature is calculated as described 
 
under “Outdoor Reset Operation” and “Target 
 
Temperature Boost” when the outdoor sensor is 
 connected. 
 
High limit operations
The Crest SMART TOUCH control has two (2) integral limits, 
one auto reset and one manual reset.  The Crest also has one 
auxiliary manual reset high limit.  The integral and auxiliary 
high limits are UL353 certified.
When the outlet temperature exceeds 195°F (90.6°C) (Installer 
Adjustable Parameter), integral auto reset high limit action 
occurs.  The boiler will shut down until the outlet water cools 
down and the timer expires.
If the outlet temperature exceeds 200°F (93.3°C) (User 
Adjustable Dial), auxiliary manual reset high limit action 
occurs.  The boiler will shut down until the outlet water cools 
down and the boiler is reset through the user interface.
If the outlet temperature exceeds 205°F (93.3°C) (Installer 
Adjustable Parameter), integral manual reset high limit action 
occurs.  The boiler will shut down until the outlet water cools 
down and the boiler is reset through the user interface.
Low water cutoff protection
A low water cutoff device with test and reset functionality is 
provided in the boiler as standard equipment.
Flow sensing device
The SMART TOUCH control module uses temperature sensing 
of both supply and return temperatures of the heat exchanger.  
If the flow rate is too low or the outlet temperatures too high, 
the control module modulates down and will shut the boiler 
off.  This ensures boiler shutdown in the event of low flow 
conditions.
Outdoor reset operation, if used
Target temperature with outdoor reset
This feature improves the system’s efficiency as the outdoor 
temperature warms up.
See the Crest Service Manual to change the settings.
Reset curve
The reset curve looks at outdoor air temperature and adjusts 
the set point.
 NOTICE
If a mechanical flow switch is required to 
meet local code requirements the Crest 
boiler can be equipped with a field supplied 
outlet switch.  Please reference page 38 of 
this manual for more information.