Instructions On The Water Heater; Safety Devices - Lochinvar AMP 200-9 Installation, Commissioning, User & Maintenance Instructions

6.2

Instructions on the water heater

The water heater has some safety instructions
on its cover:
 The text "A pressure relief valve must be
fitted".
 The text "Mount the delivered temperature
and pressure valve in this connection".
 The text "Check screwed wire connections".
6.3

Safety devices

Safety devices of the water heater:
Float switch
(boil dry protection)
Overheat thermostat
Safety devices of the installation:
Expansion valve
Non-return valve
Pressure-reducing valve
Expansion vessel
T&P valve
(1)
(Temperature and pressure
relief valve)
1- All water heaters have a T&P valve connection. Lochinvar recommends to always use a T&P valve.
6.3.1 Boil Dry Protection
The boil dry protection mechanism is a float
switch which monitors the water level
approximately halfway up the tank above the
elements. If there is insufficient water present in
the tank, the float (1) hangs downwards. If the
tank is filled with water then the float is moved
upwards by the water.
0313545_AMP_UKUK_V2.0, 03-02-2020
The float switch monitors the water level, approximately halfway up
the tank, above the elements. If there is insufficient water present
in the tank, then the float hangs down (reed-contact open). If the
tank is filled with water then the float is moved upwards by the
water (reed-contact closed).
The overheat thermostat detects the temperature of the water in
the tank. When the temperature become too high (>93°C) the
thermostat locks the elements. The thermostat can be manually
reset (red button) when the temperature of the water is below
20°C.
The expansion valve is a pressure relief valve. The expansion
valve prevents excessive pressure in the tank and back flow of
expansion water into the cold water main supply.
The non-return valve prevents back flow of expansion water into
the cold water main supply.
The pressure-reducing valve reduces the water mains pressure, if
necessary.
The expansion vessel is a small tank that is used to protect closed
water systems from excessive pressure, due to thermal expansion
of the water in the tank.
The T&P valve is a temperature and pressure relief valve which is
activated when:
-
The temperature exceeds 97°C.
-
The pressure exceeds 7 bar.
6.3.1.1 Working principle
The working principle is as follows: the float arm
moves a magnet that is in contact with a reed-
contact, which is located in the black plastic tube
at the end of the float switch. The movement of
the magnet and float arm changes the magnetic
field and the reed-contact is opened or closed.
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