A.O. Smith 110, Руководство по устранению неисправностей

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Troubleshooting Guide
9|
Page
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The flow adjustment valve could be obstructed due to hard water scale or debris, causing lower
than expected water flow. Verify water flow with a graduated container or with the remote
temperature controller, if one is installed.
•
The output thermistor could be compromised. This component may be checked by entering the
Diagnostics Mode on a remote controller, if one is installed. Turn power off to the unit and run
cold water through it; check to see if the inlet and outlet temperatures read the same on the
remote. For instructions on how to do this, refer to the Maintenance Sheet, packaged with
every water heater and located behind the front panel of the unit.
TEMPERATURE FLUCTUATES WHEN A FIXTURE IS OPENED
•
Make sure the unit is installed properly using the Proper Installation section (p. 6) of this guide.
•
Check the flow and temperature right at the unit at the pressure relief valve. If the flow rate
and temperature are correct at the PRV, then the problem resides elsewhere in the plumbing
line. The following could be plumbing line problems:
o
Check for cross plumbing between cold water lines and hot water lines. See the
Procedures section (p. 21) for instructions.
o
Check to see that a check valve is installed between the pump discharge and the
connection to the cold water supply. Inspect the check valve for proper operation. If
there isn’t one installed, or if it is malfunctioning, cold water may be back ‐ feeding into
the system.
o
Problems with a recirculation system:
ƒ
Check that a check valve is installed between the pump discharge and the
connection to the cold water supply.
ƒ
Check to see if the pump is operating properly.
ƒ
Check for air cavitation. The pump will be very hot or chattering.
ƒ
Check the directional indicator on the pump flange.
ƒ
Check the sizing of the pump – a minimum flow of 2 gpm is required.
•
Check gas supply
o
Verify the gas supply lines are sized for the maximum Btu/h demand, as indicated in the
Proper Installation section (p. 6) of this guide (See the specification page p.3 at the
beginning of this manual for gas input rating).
o
For LP models, there may not be enough gas left in the propane tank.
o
Verify that the supply gas pressure is within specification, not only when the heater is in
standby, but while the heater is running on maximum fire as well. This may be caused
by a malfunctioning gas supply regulator.
•
Venting
o
Verify that the exhaust venting is installed to manufacturer’s specification.
o
Verify that the vent run does not exceed the maximum limit (50 ft.)
•
The filter on cold water inlet should be clean; look for signs of hard water scaling.
•
Check to make sure that the clear tube between the proportional gas valve and the bottom of
the combustion chamber is connected.
•
On well systems or even on some city water systems, water pressure fluctuations (especially on
low flow) of 8 to 10 psi will result in flow rate fluctuations, which will in turn result in minor
temperature fluctuations.
•
Flow sensor or water control valve may be compromised. Contact the Technical Department.