Specifications

TM012 Rheem Electric Water Heaters Service Instructions REV: B
Date of Issue: 03/06
This document is stored and maintained electronically by
Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
6
Components and their Function
Temperature and Pressure Relief Valve
A valve designed to provide automatic relief by discharging water in case of excessive
temperature, pressure or both.
Never fit a T&PR Valve with a pressure rating greater than that indicated on
the product-rating label.
Pressure Limiting Valve (P.L.V.)
A valve that controls its outlet pressure to a predetermined limit.
Outlet Delivery Tube (Dip Tube)
A plastic tube installed in the hot water outlet of the water heater cylinder to conduct water
from the highest point to the outlet connection. It also acts as a fitting liner.
Inlet Delivery Tube (Dip Tube)
A plastic tube installed in the cold water inlet of the water heater cylinder to assist with
stratification. It also acts as a fitting liner.
Diffuser
A plastic device installed in the cold water inlet of the water heater cylinder to assist with
stratification. It also acts as a fitting liner.
Fitting Liner
A plastic tube installed in the cold-water inlet of the water heater to provide protection
against corrosion through the life of the water heater.
Anode (Sacrificial)
A metal alloy electrode installed in the water heater cylinder that by galvanic action
protects the cylinder from corrosion.
Over Temperature Energy Cut Out (E.C.O.)
A temperature-sensing device in combination with the thermostat that automatically cuts
off the supply of electrical energy to prevent excessive water temperature occurring. This
device will not reset automatically but may be manually reset once temperatures have
fallen to a safe level.
Thermostat
A device, responsive to temperature, which controls the supply of electrical energy to the
element to maintain the stored water at the required temperature.
Heating Unit (Element)
A tubular device containing an electric resistance element that converts electrical energy
to heat. Standard ratings are 1.2, 1.8, 2.4, 3.6, 4.8 and 6.0Kw
Non-simultaneous (Top) Thermostat – Twin Element Models
A device responsive to temperature which controls the supply of electrical energy to the
top element to maintain the stored water at the required temperature. It also switches the
neutral supply between the top and bottom elements to ensure only one element can be
operational at any time. This is known as non-simultaneous operation.