A.O. Smith 52, Инструкция по эксплуатации

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HIGH TEMPERATURE LIMIT CONTROLS (ECO)
Both the ELECTRONIC CONTROL and SURFACE MOUNT
CONTROL model water heaters are equipped with one or
more ECO (energy cut off) non adjustable high temperature
limit control(s). An ECO is a normally closed switch that opens
(activates) on a rise in temperature. If the ECO switch contacts
open (activate) due to abnormally high water temperatures it
will lock-out and disable further heating element operation.
It is important that a qualified service agent be contacted to
determine the reason for the ECO activation before resetting
the ECO. Once the reason has been determined and corrected
the ECO(s) can be reset as follows:
SURFACE MOUNT CONTROL MODELS
Surface Mount Control models have multiple surface mounted
Thermostat/ECO combination controls. One for each installed
heating element - see the Surface Mount Control wiring
diagrams in this manual. The ECO high temperature limit switch
contacts on each control will open when the tank temperature
reaches approximately 200°F/93°C. If activated, the ECO
reset button will be slightly extended and stiff to the touch.
When the ECO switch contacts open (activate) voltage to ONE
heating element ONLY is terminated to prevent further heating
operation of that element. Voltage may still be present at other
heating elements and they may still be heating the water.
The ECO is a manual reset switch. Should one or more ECO
activate, the tank temperature must drop below 120°F/49°C
before an ECO can be reset. To manually reset an ECO:
1. Disconnect the power supply to the water heater.
2.
Allow the tank temperature to cool below 120°F/49°C.
3. Remove the front control cover from the effected control(s).
4. Press the manual reset button on each of the effected
controls.
5. Once the control(s) has been reset the control cover should
be replaced prior to restoring power to the water heater.
ELECTRONIC CONTROL MODELS
The ECO high temperature limit switch is located inside
the immersion Temperature Probe (two red wires) on
ELECTRONIC CONTROL models. The ECO switch contacts
will open when the water temperature reaches approximately
202°F/94°C. When the ECO switch contacts open (activate)
the electronic control system locks out and displays a Fault
message. Voltage to the contactor coils and heating elements
is terminated to prevent further heating operation.
Should the ECO activate, the water temperature must drop
below 140°F/60°C before the control system can be reset.
Once the water temperature has cooled below this point the
power supply to the water heater must be turned off and on
again to reset the control system.
THERMOSTAT CONTROLS
The water heaters covered in this instruction manual are
equipped with adjustable thermostat controls to control water
temperature. Hot water temperatures required for automatic
dishwasher and laundry use can cause scald burns resulting
in serious personal injury and/or death. The temperature at
which injury occurs varies with the persons age and duration of
exposure. The slower response time of children, the elderly or
disabled persons increases the hazards to them. Never allow
small children to use a hot water tap or draw their own bath
water. Never leave a child or disabled person unattended in
a bathtub or shower.
The water heater should be located in an area where the
general public does not have access to set temperatures.
Setting water heater temperatures at 120°F (49°C) will reduce
risk of scalds. Some areas require settings at specific lower
temperatures.
THERMOSTAT SETTINGS - SURFACE MOUNT CONTROL
Adjustment of temperature controls on surface mounted
controls is to be performed by a qualified service agent at
initial start-up.
These models have multiple thermostat/ECO combination
controls one for each heating element installed. These
thermostats are set from the factory at 140°F/60°C. Set
the thermostat dial at the lowest setting which produces an
acceptable hot water supply. This will always give the most
energy efficient operation.
The water heater is supplied with thermostats that may come
from different manufactures and have different temperature
indications as described below.
THERMODISC THERMOSTATS
Thermodisc thermostats are adjustable from approximately
120°F (49°C) (lowest setting) to 181°F (83°C) (highest setting)
see
Figure 10
. These thermostats are set from the factory at
approximately the 140°F (60°C) setting. The over temperature
device (ECO high limit) attached to each thermostat has a
manual reset.
APCOM THERMOSTATS
Apcom thermostats have three designated set points; LO,
MED and HI. See
Figure 11
. The approximate equivalent
temperatures for these three settings are: LO = 140°F (60°C),
MED = 160°F (71°C) and HI = 181°F (83°C). These thermostats
are set from the factory at the MED 140°F (60°C) setting. The
over temperature device (ECO high limit) attached to each
thermostat has a manual reset.
TEMPERATURE REGULATION
Printed on 2/8/2018 9:05 AM CT