21
6.11
Plastic piping in the heating system
When plastic pipes are used in the central heating system and
NOT
oxygen diffusion proof to standard DIN 4726,
these should be separated from the boiler system by using a plate heat exchanger. Diffusion (through the plastic)
can cause air to enter the heating system. This could damage the boiler, pumps and other components in the system.
Be aware that plastic piping is often used in under floor heating systems. When no measures have been taken to
prevent the entrance of air into the boiler system, the warranty of the boiler and any boiler part may be deemed
invalid.
6.12
Automatic air vent
An automatic air vent is mounted on the boiler to remove the air from the water circuit.
NOTICE: this automatic air vent is only used for bleeding the air in the heat exchanger of the boiler. One or more
external automatic air vent(s) and/or air separators must always be mounted in the heating system to take out the air
trapped in the heating circuit.
DE-AERATION PROGRAM. When the unit is fired for the first time the unit starts a de-aeration program. One cycle
is 5 seconds pump running and 5 seconds pump off. A complete de-aeration program consists out of 3 cycles. The
de-aeration program can be interrupted/stopped by briefly pressing the service button during the program.
6.13
Automatic water filling systems
When using an automatic water refill system some precautions should be taken (fresh water is bringing fresh oxygen
into the system), like installing a water meter to measure and evaluate the total water volume that is added to the
system. This to detect and eliminate any water leakage as soon as possible.
When an automatic water refill system is used, some form of logging should take place to prevent continuously filling
of the system with large amounts of oxygenated fresh water. This can happen when a leak in the system is not
detected and the total added water amount is not being logged.
6.14
Water pressure
First and for all, the installation should be designed and built conform all applicable regulations and standards, in-
cluding the right safety valves. IMPORTANT: Always keep the pressure in the boiler lower than the value at which its
safety valve opens.
Sensor
A water pressure sensor has been built into the boiler. With this sensor, minimum water pressure in the boiler is 0,8
bar and maximum pressure is up to 4,0 bar (sensor values). Normal water pressure is supposed to be between 1,5
and 2,0 bar.
The pressure sensor will stop the boiler from firing when the water pressure drops below 0,8 bar, and start the boiler
firing again when the water pressure reaches above the 1,0 bar. These values can be changed in the boiler control
settings.
NRV
NRV
S-CB
+
TOP VIEW
S-CB
+
TOP VIEW
S-CB
+
TOP VIEW
HEATING ZONE
EXTERNAL
SYSTEM
PUMP P3
EXTERNAL
BOILER
PUMP P1
EXTERNAL
BOILER
PUMP P1
EXTERNAL
BOILER
PUMP P1
HEATING
ZONE
EXTERNAL
SYSTEM
PUMP P3
