use suitable guaranteed products for heating systems
(see next section), that do not harm metals, plastics or
rubber. The manufacturer declines any liability for da-
mage caused to the generator by failure to properly
clean the system.
Make the respective connections, paying attention to the symbols provided on the unit.
Frost protection system, antifreeze liquids, additives and inhibitors
If necessary, the use of antifreeze liquids, additives and inhibitors is allowed, only and exclusively
if their manufacturer guarantees that the products are suitable for use and do not cause damage
to the boiler's heat exchanger.or other components and/or materials of the boiler and system. It is
prohibited to use generic antifreeze liquids, additives or inhibitors that are not expressly suitable
for use in heating systems and compatible with the materials of the boiler and system
System water characteristics
ALHENA TECH H boilers are suitable for installation in heating systems with non-signifi-
A
cant entry of oxygen (ref. systems "case I" EN14868). A physical separator (e.g. plate heat
exchanger) must be provided in systems with continuous entry of oxygen (e.g. underfloor
systems without antidiffusion pipes or open vessel), or intermittent (less than 20% of sy-
stem water content).
The water inside a heating system must comply with the applicable laws and regulations,
the characteristics required by UNI 8065, and the indications of EN14868 (protection of
metal materials against corrosion) must be observed.
The filling water (first filling and subsequent replenishment) must be clear, with hardness
below 15°F and treated with suitable chemical conditioners against the initiation of corro-
sion, that are not aggressive on metals and plastics, do not develop gases and, in low-
temperature systems, do not cause proliferation of bacterial or microbial masses.
The water contained in the system must be checked regularly (at least twice a year during
the season of use, as required by UNI8065) and have: a possibly clear appearance, a har-
dness lower than 15°F for new systems or 20°F for existing systems, a PH higher than 7
and less than 8.5, an iron content (Fe) less than 0.5 mg/l, a copper content (Cu) less than
0.1 mg/l, a chloride content lower than 50mg/l, an electrical conductivity lower than 200
μS/cm, and must contain chemical conditioning agents in a concentration sufficient to pro-
tect the system at least for one year. Bacterial or microbial loads must not be present in
low temperature systems.
Only use conditioners, additives, inhibitors and antifreeze liquids declared by the producer
suitable for use in heating systems and that do not cause damage to the heat exchanger
or other components and/or materials of the boiler and system.
Chemical conditioners must ensure complete deoxygenation of the water, contain specific
protective agents for yellow metals (copper and its alloys), anti-scaling agents for limesto-
ne, neutral PH stabilizers and, in low-temperature systems, specific biocides for use in he-
ating systems.
Recommended chemical conditioners:
SENTINEL X100 and SENTINEL X200
FERNOX F1 and FERNOX F3
The unit is equipped with a frost protection system that activates the boiler in heating mode
when the system flow water temperature falls below 6°C. The device is not active if the
power and/or gas supply to the unit is turned off. If necessary, to protect the system use a
suitable antifreeze liquid that meets the above requirements and provided for by UNI 8065.
318
cod. 3541V622 - Rev 00 - 05/2022
ALHENA TECH H
EN