Raypak XTherm Series Installation & Operating Instructions Manual page 38

Ignition Control Functions
When there is a call for heat, and all safeties are
closed, then the combustion air blower starts to purge
air from the combustion chamber. After the pre-purge,
the igniter is energized. The standard ignition module
will lock-out after failing to light 3 times during a call
for heat. To reset the lock-out, press and release
the RESET button located on the user interface. The
control will automatically reset after 1 hour. When in
lock-out the control will run the blower through a post-
purge cycle.
The single-try ignition module (part of the CSD-1
option) will attempt to light only one time before lock-
out occurs. To reset the lock-out, press and relase the
RESET button located on the user interface.
Turning off the power to the heater WILL NOT
reset the single-try ignition module.
NOTE: Ignition modules are common for all model
sizes. However, model-specific operating parame-
ters are defined by their respective ID cards.
High Limit—Manual Reset
This heater is equipped with a fixed-setting manual
re-set high limit temperature device as standard. It
may also have an additional optional adjustable man-
ual reset high temperature device.
The optional manual reset high limit is located inside
the cabinet on the upper left corner post. Access the
limit by hinging the control box open to view and make
adjustments.
STANDARD
Fig. 43: High Limit (Manual Reset)
Standard
The fixed-setting manual reset high limit is built into
the PIM, and utilizes a dual element sensor located
on the outlet.
H 235ºF
WH 180ºF
P 150ºF
OPTIONAL
To reset a high limit lock-out, press and release the
RESET button located on the user interface.
High Limit—Auto Reset (Optional)
This heater may be equipped with an optional adjust-
able auto-reset high limit temperature device.
The optional adjustable auto reset high limit is locat-
ed inside the cabinet on the upper left corner post.
Access the limit by hinging the control box open to
view and make adjustments. Adjust the setting to
approx. 20°F (11°C) above desired outlet temperature.
Fig. 44: Adjustable High Limit (Auto Reset)
Flow Switch
This standard, dual-purpose control, mounted and
wired in series with the main gas valve, shuts off heat-
er in case of pump failure or low water flow.
Fig. 45: Flow Switch
Low Water Cut-Off (Optional)
The optional low water cut-off automatically shuts
down the burner whenever water level drops below the
level of the sensing probe. A 5-second time delay pre-
vents premature lockout due to temporary conditions
such as power fluctuations or air pockets.
46: Low Water Cut-Off
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