Plumbing Diagram; Operation - Rheem 70103 Service Instructions Manual

Plumbing Diagram

Cold mains pressure water must be piped
and connected to the RP½/15 inlet fitting
located on the left hand side underneath
the BWU.
An accessible isolating valve must be
installed near the BWU.
The BWU contains an inlet strainer on the
water inlet connection. Where poor water
quality is present it is recommended to
install an additional auxiliary filter.
The vent pipe is to be made of a material
that cannot be degraded by continuous
steam (i.e. copper).

Operation

701, 702 and 703 Series BWU operate on 230 - 240 volts AC and will deliver gravity fed
boiling water via a lever operated tap mounted on the BWU.
Sequence of Operation
Refer to BWU Sequence of Operation Component Diagrams' on page 10 to view
components shown in brackets e.g. (1).
1. When power is supplied to the BWU the control board relay (1) is energised. If the low
level probe (2) does not detect water the inlet solenoid valve (3) is energised allowing
water to enter and partially fill the boiling water tank (4) until 15 seconds after the low
level probe (2) detects water. Note: Upon initial filling and calibration, the inlet solenoid
valve (3) is energised until 30 seconds after the low level probe (2) senses water.
2. When the BWU is operated for the first time, or auto calibration mode is selected (5),
the unit will enter auto calibration mode. When in auto calibration mode the BWU will
perform three heating operation cycles in which to determine and program the
optimum boiling water temperature setting according to altitude. The optimum boiling
water temperature is termed 'Treq' which is the water temperature the BWU will
maintain the boiling water at after calibration. Auto calibration mode takes
approximately 18 – 30 minutes to perform (depending upon model capacity) and
should not be interrupted.
3. After calibration or under normal operating conditions; if the boiling water thermistor (6)
detects a temperature of less than 94ºC, or less than or equal to Treq
board triac (7) allows power to the boiling water element (8) on a percentage basis of
between 20% (48 volts) to 100% (230 - 240 volts) depending upon the temperature,
i.e. higher temperature difference equals higher percentage basis.
TM063 701, 702 & 703 Series Boiling Water Unit Service Instructions
Revision D: Feb 2017
This document is stored and maintained electronically by
Water Inlet and Vent Connections
Service. All printed copies not bearing this statement in RED are deemed "uncontrolled"
All models have same pipework configuration
-
2ºC, the control
8