Risk Of Freezing; Water Quality - Mitsubishi Electric Climaveneta i-BX-004-013M Installation, Operation And Service Manual

WATER CONNECTIONS
Components
The following components should be installed for correct
installation of the unit:
1. Two pressure gauges with a suitable scale (inlet and out-
let);
2. Two vibration damper joints (inlet and outlet).
3. Shut-off valves at the inlet and outlet.
4. Two thermometers (inlet and outlet);
5. Return filter on the unit, supplied as standard (compulso-
ry), as close as possible to the unit and positioned to
allow easy access for routine maintenance.
6. All the pipes must be insulated with suitable material to
prevent the formation of condensate and heat loss.
The insulating material must be a vapour barrier.
Make sure that the control and shut off devices protrude
from the insulation.
7. At the lowest points in the system, install drain valves for
easy emptying.
8. At the highest points in the system, install automatic or
manual air vent valves.
9. The unit is fitted as standard with an expansion vessel
(configuration with integrated hydronic unit); make sure
this is correctly sized for the water content of the system

Risk of freezing

The unit must be prevented from freezing at outside air tem-
peratures around 0°C.
The following are recommended:
• use suitable percentages of antifreeze (see "Ethylene gly-
col solutions")
• protect the piping with heating sheaths,
• empty the system, making sure no water remains at the
lowest points in the circuit or there are closed valves
where water may stagnate.
Ethylene glycol solutions
Water and ethylene glycol solutions used as a heat carrier in
the place of water reduce the performance of the unit.
Multiply the performance figures by the values given in the
following table.
The heat pumps must be fitted with a filling/top-up sys-
tem connected to the return line and a drain valve in the
lowest part of the system.
Systems containing antifreeze or covered by specific
legislation must be fitted with low-loss headers.

Water quality

The water used in the system and domestic hot water cir-
cuits must comply with the following characteristics:
14 i-BX-(Y)_i-BX-N-(Y) EN
and the expected operating temperature, otherwise
install an additional expansion vessel.
10. The connection piping should be supported in such a
way as to avoid it weighing on the unit.
The correct operation of the components that help ensure
the safety of the appliance and the system should be
checked regularly:
• make sure the filters are clean
• check operation of the flow switches installed.
• Make sure that the frost protection heaters on the heat
exchanger are powered when the unit is OFF
Water flow to the heat pump must conform to the values
shown in the section on "General Technical Data".
The flow of water must be maintained constant during oper-
ation.
The water content of the unit must be such as to avoid dis-
turbing operation of the refrigerant circuits.
It is recommended to use non-toxic food grade antifreeze,
compliant with the standards in force in the countries where
the unit is used, if domestic hot water production is also fea-
tured.
The antifreeze used must be corrosion inhibited and com-
patible with the water circuit components.
Freezing point (°C)
0 -5
Percentage of ethylene glycol by weight
0 12%
cPf 1 0,985
cQ 1 1,02
cdp 1 1,07
cPf: cooling capacity correction factor
cQ: flow rate correction factor
cdp: pressure drop correction factor
PH 6-8
Electrical conductivity less than 200 mV/cm (25°C)
Chlorine ions less than 50 ppm
Sulphuric acid ions less than 50 ppm
Total iron less than 0.3 ppm
Alkalinity M less than 50 ppm
Total hardness less than 50 ppm
Sulphur ions none
Ammonia ions none
Silicon ions less than 30 ppm
I A
-10 -15 -20
20% 28% 35% 40%
0,98 0,974 0,97 0,965
1,04 1,075 1,11 1,14
1,11 1,18 1,22 1,24
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