Ariston IHUB 4 - Manual (Page 8)

Occasionally, the high temperature limit shut off device may trigger and shut the
system down. This occurs when water temperature exceeds 190° F and shuts off
power to the heating element. The shut off device may also trigger from a power
outage or electrical storm.
To reset:
1) IMPORTANT: Disconnect heater from electrical power.
2) Remove front cover plate (C fig. 3/4).
3) Firmly press reset button (B fig. 3/5).
4) Replace cover plate, reconnect power.
5) IMPORTANT: Check the operation of the thermostat, turn temperature dial from
high to low, if the red light does not go off on low setting, turn off power supply and
call a service person to replace thermostat.
6) If the system works, place dial setting to desired setting.
Note: a lower setting is more economical, and reduces the risk of scalding.
CAUTION: Call a technician if the high limit needs to be reset frequently.
Troubleshooting
1. Make sure the power supply is on and working.
2. If light does not come on, check that the reset button is pushed in; follow steps from
previous section.
3. If the indicator light works properly but temperature does not get hot a tap, test for
a plumbing crossover; shut off cold supply to heater and open hot water tap. There
should be no water flowing. Any continued flow indicates a crossover which will
effect the temperature and will need to be corrected.
4. Replace heating element (see previous section on changing the heating element).
1. If the light does not come on, but water gets hot, check for faulty bulb.
2. Check reset button; follow steps from previous section.
1. Brown or rusty water indicates a “spent” anode rod. Replace anode rod.
1. Smelly water could be due to an unusual reaction between local water and the
heater’s anode rod. Check anode rod.
1. Remove cover plate and turn the temperature selector dial (D fig. 3/5) counter
clockwise to lower temperature. If temperature never lowers then replace thermostat.
1. Under Instructions for Use see Temperature Setting instruction.
1. Check water fittings and T & P fitting on top of tank.
2. Remove front cover and inspect heating element gasket.
Water does
not get hot
Light not on
Brown water
Odor in water
Water is too
hot
Water not
hot enough
Resetting
High Limit
Switch
Leaking
9
1. Turn off power supply and drain the heater (see previous section).
2. Remove the heating element (see section on Removing the Heating Element).
3. Install new element with gasket, making sure the gasket and element are positioned
correctly. Tighten the retaining nuts and make the wire connections.
4. Refill tank with water before restoring power.
1. Turn off power supply.
2. Disconnect the 2 push/pull type wires on thermostat.
3. Loosen the two brass screws at right side of thermostat and pull wires out.
4. Unscrew and remove the two phillips screws holding the thermostat down.
5. Install new thermostat and re-attach wiring and screws.
Changing
the heating
element
Changing
the
thermostat