Startup - Nyle C25W Installation, Operation, Service, Maintenance, Limited Warranty

This start-up refers to several tools and test instruments needed
to complete the procedure. See Required Tools and Materials
on page 18.
•
Turn off power to the water heater
before performing any service.
•
Label all wires prior to disconnecting
when performing service. Wiring errors
can cause improper and dangerous
operation.
•
Verify proper operation after servicing.
•
Failure to follow these instructions can
result in personal injury or death.
1. Ensure the Installation Checklist has been completed.
2. Ensure the HPWH, storage tank and water system has been
purged of air and all valves are in the position for normal
operation.
3. Turn on power at the circuit breaker or disconnect switch
serving the HPWH.
If the HPWH does not start immediately:
• Wait 5 minutes in case the anti short cycle timer has halted
operation. This control system feature protects the HPWH
from rapid short cycling that can cause permanent
damage to the unit.
• Ensure the operating set point on the tank temperature
control is adjusted high enough to initiate a call for heat.
The recommended setting is 120°F to 150°F (29°C to 66°
C).
• DO NOT set the operating set point on the tank
temperature control above 150°F. See Water Temperature
Range on page 11.
• Ensure the Differential Set Point is not set too high. Higher
differential settings will cause greater temperature swings
in system temperature. Lower differential settings can
cause unit short cycling. The recommended setting is 10°F.
• If the unit does not start after all of the above procedures
have been followed. Refer to the troubleshooting section
of this manual.
4. Securely attach surface mount thermometers or temperature
sensors to the inlet (entering) and outlet (leaving) water lines
near the HPWH cabinet. If there are thermometers installed
in the inlet and outlet in close proximity to the HPWH water
connections they can be used for the following check. Ensure
the water outlet (supply) and inlet (return) valves are fully
open. Start the HPWH and allow it to operate for 5 minutes.
With the HPWH operating record the inlet and outlet
temperatures.
During normal operation, the outlet line should be 8°F to 12°F
(4°C to 7°C) hotter than the inlet line. This is the temperature
rise through the heat exchanger inside the HPWH unit. Note:
Temperature rise and water flow rate through the heat
exchanger inside the HPWH are uniformly linked. As water
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Electrical Shock Hazard
START UP
flow is decreased the temperature rise will increase and as
water flow is increased the temperature rise will decrease.
Because of this relationship between temperature rise and
flow rate this test can be useful to determine if the flow rate
through the heat exchanger is adequate. Other factors may
also affect water flow rate and temperature rise such as
debris or lime scale build up inside heat exchanger or water
pump operation.
If the temperature rise through the HPWH is
consistently lower than 8°F the outlet (supply) valve can
be throttled slightly closed to reduce the water flow rate.
This may be necessary on installations with a minimum of
water piping between the HPWH and the water system or
tank.
Throttling should be done in small increments, no more than
1/8 turn of the valve handle at a time. The HPWH must be
allowed to run for approximately 5 minutes between each
adjustment before the temperature rise is measured again.
If the outlet valve is throttled during start up, mark the valve
position and remove the valve handle to ensure it is not
accidentally changed.
If the temperature rise through the HPWH is consistently
greater than 12°F the water flow may be restricted. Ensure
all water valves between the HPWH and the tank or water
system are fully open. Ensure the e x t e r n a l water
pump is running. If the temperature rise continues
to be excessive call the toll free technical support phone
number: 1-800-777-6953 ext. 208
5. Using thermometers or temperature sensors, measure the
temperature of the incoming source water to the HPWH
and the outgoing source water leaving the unit. The outgoing
temperature should be 12°F to 20°F (7°C to 13°C) cooler
than the incoming. The higher the flow rate the lower the
temperature differential will be.
6. When all of the above procedures are complete, adjust
the tank temperature control set point to desired system
temperature, not to exceed 150°F (66°C). Remove all test
instruments and replace all cabinet doors.
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