Rheem 70103 Service Instructions Manual page 9

4. After first time calibration or after drawing boiling water; the control board will
incrementally fill and heat the water in the boiling water tank (4). After the first
incremental fill, the water in the boiling water tank (4) is heated to Treq
time the control board will energise the inlet solenoid valve (3) until the water in the
boiling water tank (4) is at
water tank (4) (normally 4 – 15 seconds). This allows the boiling water to be heated in
increments enabling boiling water to be available in a shorter period of time. This
process is continued until the high level probe (10) detects water at which time the
inlet solenoid valve (3) is de-energised and incremental filling ceases.
5. After the high level probe (10) detects water, heating is continued until the boiling
water thermistor (6) detects a temperature equal to Treq at which time the control
board triac (7) switches off (de-energising the boiling water element (8)) and the
control board relay (1) is de-energised.
6. When the tap (9) lever is operated, boiling water is gravity fed to the tap (9) outlet. As
the water level in the boiling water tank (4) falls below the high level probe (10) the
inlet solenoid valve (3) is energised allowing water to enter the boiling water tank (4)
again in 4 – 15 second incremental fills or until the high level probe (10) detects water
again (depending upon the amount of boiling water drawn). It should be noted that if
the water level in the boiling water tank (4) falls below the low level probe (2) at any
time, the boiling water element circuit is disabled until the low level probe (2) detects
water again for a period of 1 second or more.
7. When the high level probe (10) detects water again, the inlet solenoid valve (3) is de-
energised preventing water from entering the boiling water tank (4).
8. If during any stage of operation:
 The boiling water thermistor (6) becomes open or short circuited,
 The low level probe (2) is shorted to earth, or
 The control board triac (7) becomes short circuited,
The inlet solenoid valve (3) and control board triac (7) are de-energised (if on) and the
control board relay (1) will turn off (be de-energised).
Notes:
 701 & 702 series only: If the timer (5) 'off period' has been programmed and reached,
the boiling water Treq temperature is changed from calibrated Treq temperature to 0ºC,
until the next timer 'on period' is reached, or the timer (5) 'off period' is deactivated by
pressing any timer button, at which time the calibrated Treq setting will return to normal.
This is an energy saving function.
 703 Series: If the Eco timer (5) has been set and reached, again, the boiling water Treq
temperature changes from calibrated Treq temperature to 0ºC. Sleep mode is
deactivated by pressing and releasing the 'ECO' button, at which time the calibrated
Treq setting will return to normal. This is an energy saving function.
TM063 701, 702 & 703 Series Boiling Water Unit Service Instructions
Revision D: Feb 2017
This document is stored and maintained electronically by
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3 ºC of Treq which allows more water to enter the boiling
Service. All printed copies not bearing this statement in RED are deemed "uncontrolled"
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2ºC at which
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