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24
24V terminal strip, other than those approved/supplied by the
manufacturer.
7 .13
Check/control water chemistry
9
WARNING:
D
o not use petroleum-based cleaning or sealing
compounds in heating system. Damage to elastomer seals
and gaskets in the system could occur, resulting in substantial
property damag
e.
Water pH between 7.0 and 8.0
− Maintain a water pH over 7.0 for a stainless steel heat exchanger
and below 8.0 if there are aluminium components in the heating
system. Check with litmus paper (swimming pool test strip)
or have the system chemically an
alyzed by water treatment
company.
− If pH differs from above, consult the local water treatment
company for treatme
nt needed.
Hardness less than 9 grains
− It is recommended that water hardness be below 9 grains.
− Consult the local water treatment companies for unusually hard
water areas (above 9 grains hardness).
Chlorine concentration less than 50 ppm
− Do not fill boiler or operate with water containing chlorine in
excess of 50 ppm.
− Do not use the boiler to directly heat a swimming pool or spa
water.
Clean system to remove sediment
−
During installation, es
pecially when replacing existing equipment,
it is recommended to thoroughly flush the system (without the
boiler connected) to remove sediment. The high-efficiency heat
exchanger can be damaged by build up or corrosion due to
sediment.
− Flush system until water runs clean and you are sure piping is
free of sediment.
7 .14
Freeze protection (when used)
9
WARNING:
NEVER use automotive or standard glycol
antifreeze, even ethylene glycol made for hydronic systems.
Use only glycol fluids certified by a glycol manufacturer
as suitable for use with stainless steel, verified in glycol
manufacturer’s li
terature.
Test/replace glycol fluid
− For systems using glycol fluids, follow glycol manufacturer’s
instructions to verify the inhibitor level and that other fluid
characteristics are satisfactory.
− Do not exceed 40 % of the system volume with glycol fluids.
NOTICE:
Glycol must be replaced periodically due to degradation
of inhibitors over time. Follow all glycol manufacturer’s instructions.
9
Throroughly clean and flush any system that has used glycol
before installing the new
boiler. Provide the boiler owner with
a material safety data sheet (MSDS) on the glycol used (if
requested).
− Determine glycol fluid quantity using total system water content,
following the glycol manufacturer’s instructions. Remember to
include expansion tank water content.
NOTICE:
Boiler capacities can be reduced up to 20% when glycol
is used.
− Local codes may require a backflow preventer or actual
disconnect from city water supply.
7 .15
Casing removal
To access the components inside, remove the casing as indicated
below:
- locate and unscrew the 2 screws (
A
- figure beside) that attach
the door to the casing
- push the two tabs in the lower corners (
C
) to disengage the door
from the casing
- lift the door upwards to remove it from the top tabs (
B
), set door
aside.
Removal of the side panels
− Locate and remove the 2 screws (
D
) that secure the side panel
to the appliance.
− Gently prise the side panel forward to release it from the securing
tabs on the appliance rear.
NOTICE:
If the side panels have been removed, reassemble them
in the original position by referring to the adhesive labels on the
side walls.
NOTICE:
If the front panel is missing, it must be replaced.
NOTICE:
The noise absorbing panels inside the front and side
walls ensure an airtight seal for the air supply duct.
NOTICE:
It is ESSENTIAL to correctly reposition the panels after
reassembly to ensure limited air leakage.
B
C
A
D
D
7 .16
Initial filling of the system and air purge
NOTICE:
The initial filling of the system and each later refill must
be done with the electrical supply ON and the boiler in OFF mode.
NOTICE:
On initial powerup and every time power is cycled, the
automatic pump purge occurs.
Once the hydraulic connections have been carried out, fill the
heating system.
- For existing systems, the entirety of the system mush be drained
and flushed with a pH neutral solution. Refer to section “11.3
Initial flushing of the system” page 44 for details.
- See the Application Guide (available on HVAC Partners) for
system piping recommendations.
- Follow all local codes and regulations for installation and piping
of boiler.
This operation must be carried out when the system is cold by
following the steps below:
− Ensure both supply and return service valves are open.
− Open the cap of the automatic air vent valve (
A
) behind the
circulator pump by two or three turns to allow a continuous venting
of the air, leave the plug of the valve (
A
) open permanently with
the operation of the boiler.
− Locate the installed silicone tube to the manual air vent valve (
D
)
and insert the open end into a bucket to collect the water that
eventually comes out after the air purge.
− Open the manual air vent valve (
D
).
9
WARNING:
Water flushing through the manual air vent valve
(D) can cause instant and severe burns when opening the air
vent valve on the heat exchanger. Open this valve only when
the water in the system is cool.
− Make sure the cold water inlet tap is open.
− Open the filling tap (
B
).
− Switch ON the 120V electrical supply to the boiler. Operation
mode should be left in OFF.
−
Wait until only water comes out continuously from the manual air
vent valve, close the valve (
D
).
− Check the pressure value on the screen: when the pressure
indicated by the sensor is between 15-21 psi (1-1.5 bar) close
the filling tap (
B
). To get the display screen to show the pressure
value refer to INFO MENU in “11.10 Access to the INFO menu”
page 47
− Cycle the line power supply off and after a few seconds back on
while leaving the boiler in OFF operation mode. This will initiate
pump purge to start the
venting cycle.