Combi - Cadet 40-120 Installation And Service Manual

14

Combi

Setting DHW target temperature
An excessively high DHW temperature
WARNING
set point can result in serious injury. The
minimum effective temperature should
be used. Verify the installed anti-scald
device requirements to determine an
appropriate DHW temperature range.
Consider the following factors when determining ideal DHW
set point temperature:
– Cold water supply temperature
– Anti-scald device requirements
– Flow rates
Lower cold water supply temperatures
NOTICE
may require higher DHW temperature
settings.
Set point adjustment and anti-scald
device requirements
Determine the maximum and minimum hot water supply
temperatures required for the anti-scald device. The suggested
Cadet DHW temperature set point is typically 15°F higher
than the anti-scald device setting.
• If this temperature is not within the required range for
the specific anti-scald device, select a temperature close
to 15°F above, but still within the allowable range for the
device.
Change the DHW set point for the unit to reflect the chosen
temperature. Monitor water drawn from an outlet after the
anti-scald device to ensure that outlet temperature remains
stable at the determined set point.
•
If outlet temperature is unstable or the unit cycles off,
lower the DHW set point approximately 5°F, or until
it becomes stable while remaining within the required
range.
After the outlet temperature has stabilized, turn OFF water for
approximately 30 seconds. Turn water ON maintaining the
previous temperature and flow rate. Monitor the temperature
at the point of use until it has maintained the chosen DHW
set point.
• If the temperature at the point of use dips more than
3°F below the set point before stabilizing at the desired
temperature, increase the DHW set point and repeat the
process above.
• If the temperature does not dip, reduce the DHW
temperature and repeat the process above to determine
the minimum set point that will not cause a drop in
temperature.
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Installation & Service Manual
In some configurations it may not
NOTICE
be possible to achieve an ideal DHW
set point where there are no dips in
temperature. In this case, use the best
achievable set point that is safely within
the range required by the field-supplied
anti-scald device.
Flow rates
Verify that the Cadet will be able to maintain the established
DHW set point temperature at an expected minimum flow
rate.
•
Draw water from the unit at a minimum anticipated
(typical) flow rate and temperature. Monitor the unit to
ensure that temperature remains stable at the set point.
• If outlet temperature is unstable or the unit cycles off
during this process, lower the DHW set point and repeat
the process until a stable temperature is established.
You MUST verify the hot water inlet
WARNING
range required for the anti-scald device
and ensure that the Cadet DHW set
point is safely within this range to avoid
serious injury.
•
The anti-scald device MUST be
rated for the flow rates anticipated
for the unit.
•
DHW temperature set point
should be set at least 10°F below the
maximum allowable temperature
for the anti-scald device.