Install Instructions

3. Special Features:
The P
UREFIRE
®
control offers several special features to
give the installer options in setting up the boiler. These
options are shown in the following table and
described in detail later in this section.
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BOILER CONTROL: INTERNAL WIRING & OPERATION
Table 8.3: Control Features
Feature Description
System Response Time
Allows the installer to adjust the response time of the burner modulating control. This can be set differently for central
heating (CH) or domestic hot water (DHW) demands.
Maximum Firing Rate
Allows the installer to adjust the maximum firing rate of the burner modulating control. This can also be set differently
for CH or DHW demands.
Cascade Up to 16 boilers can operate together in stages to satisfy the CH or DHW demand.
One Hour Retry One hour after a lockout on ignition or flame failure, the PUREFIRE
®
control with reinitiate boiler operation.
Restore System Defaults
Installers or service people may reset all parameters to the factory defaults as desired. They can also save and restore
site defaults.
Adjustable Blower
Postpurge
The blower postpurge may be increased to counteract the effects of high winds or unusual wind currents.
Flame Signal Log
This troubleshooting tool captures the flame signal at four increments during the two second flame proving period. This
will help service people to quickly diagnose problems with flame rectification.
Freeze Protection
Activates pumps if water temperatures fall below the specified value. If the temperature continues to fall, the burner is
activated.
DHW Tank Warm Hold
Prevents the boiler from ramping up to high power if the control determines that the DHW demand is only due to tank
losses.
Additional Safety
Functions
Allows the installer to choose between a low water cutoff and a flow switch for water level safety shutdown.
Vent Temperature Safety
Limit
Reduces the firing rate if the exhaust vent temperature approaches the maximum limit of the vent material specified.
The control will shut down the burner if the temperature continues to climb.
System Type Presets
Automatically sets the reset calculation based on the type of heat distributions (finned tube baseboard, cast iron
radiators, cast iron baseboard, low or high mass radiant).
Temperature Boost
Increases the boiler supply temperature target if the control determines that the load cannot be met at the current reset
temperature (Outdoor Reset Modes).
Warm Weather
Shutdown
Shuts down the boiler if the outdoor temperature exceeds an installer defined limit (Outdoor Reset Modes).
Limited DHW Priority
The PUREFIRE
®
control provides DHW priority for boiler operation. The control will switch back to CH if a demand
remains present for an installer set switch time.
System Test
The PUREFIRE
®
boiler will allow the installer to operate the boiler at low power, ignition power or high power for setup
and troubleshooting.
Fault History
The last 15 blocking errors and last 15 lockout errors and the time between failures may be viewed directly from the
display.