Rinnai E75CN - Manual (Page 40)

Installation & Servicing Instructions Rinnai E-Series
40
8 Boiler controls
The boiler is provided with a fully automatic microprocessor control, called CMS
Control Management System. This control simplifies operation by undertaking all
major control functions. Initially when power to the unit is switched on it will remain on
standby. There is no indication LED on, until one of the program buttons is pressed.
The control panel display will show the relevant state. When the installation is empty
the display will show FILL.
The various parameters can be called up in two ways:
The Good-state or standard read out
The first way shows a simple display read out.
The boiler in operation will always show 'Good'. When a message is necessary this
will be shown instead of Good.
Technical read out
The second way is a technical read out. In normal situations the following will be shown:
• on the left the status in which the boiler is active;
• on the right the supply temperature in °F;
Alternately indicated by:
• the water pressure in the installation in PSI.
When a message (error or blocking code) is necessary this will be shown instead of
the technical read out.
To switch over from the Good-state to the Technical read out (and vice versa):
- Press the STEP-button for 5 seconds.
When the system has been filled the automatic de-aeration program starts, when a
program has been selected, by pressing the button for Central Heating, DHW or pump
program ( , of ). The program takes 17 minutes and stops automatically.
After this the unit will function normally. (See also 'Filling and de-aerate the boiler and
installation, chapter 9).
On a call for heating or hot water the control system will select the required water
control temperature. This water temperature is called the T-set value. On a call for
central heating the boiler ignites first at low input. The input is then changed slowly to
match the load required. The boiler operates in this way to avoid excessive water noises
and temperature overshoot. On a call for domestic hot water supply the T-set value
of central heating return water temperature is monitored. Depending on the amount of
domestic water which is withdrawn from the DHW fascility, the central heating return
water temperature, from which the input is adjusted, will vary.
Operation indication
(in the first display position by technical read out)
NOTICE
i
1
2
No heat demand
Fan pre/post purge
Ignition phase
Burner active on central heating
Burner active on DHW
Fan check
Burner off when room thermostat is demanding
Pump overrun phase for central heating
Pump overrun phase for hot water
Burner off because of to high flow temperature
Automatic de-aeration program
3
4
5
6
7
8
9
A
0
Example
Example