SAFETY
• This appliance must be used only by adult and capable people,
having received the technical information or instructions to
handle this appliance properly and safely.
• Children should be supervised to ensure that they do not play
with the appliance.
• Do not let any foreign body into the water inlet and outlet piping
of the air to water heat pump.
2.3
Important notice
• The supplementary information about the purchased
products is available through the QR printed in the
front cover. In case that no access to the website or
files are not readable, please contact your Hitachi
dealer or distributor.
• PLEASE READ THE MANUAL AND DOWNLOADED
FILES THROUGHOUT THE QR CAREFULLY BEFORE
STARTING TO WORK ON THE INSTALLATION. Failure
to observe the instructions for installation, use and
operation described in this documentation may
result in operating failure including potentially
serious faults, or even the destruction of the air to
water heat pump system.
• Verify, in accordance with the manuals which appear
in the unit, that all the information required for the
correct installation of the system is included. If this is
not the case, contact your distributor.
• Hitachi pursues a policy of continuous improvement
in product design and performance. The right is
therefore reserved to vary specifications without
notice.
• Hitachi cannot anticipate every possible
circumstance that might involve a potential hazard.
• This air to water heat pump has been designed for
standard water heating for human beings only. Do
not use this for other purposes such as for drying
clothes, heating foods or for any other heating
process (except swimming pool).
• No part of this manual may be reproduced without
written permission.
• If you have any questions, contact your service
contractor of Hitachi.
• Check and make sure that the explanations of each
part of this manual correspond to your air to water
heat pump model.
• Refer to the models codification to confirm the main
characteristics of your system.
• Signal words (NOTE, DANGER and CAUTION) are used
to identify levels of hazard seriousness. Definitions
for identifying hazard levels are provided in initial
pages of this document.
• The operation modes of these units are controlled by
the unit controller.
• This manual should be considered as a permanent
part of the air to water heat pump. It gives a common
description of and information for this air to water
heat pump which you operate as well as for other
models.
• Keep the water temperature of the system above the
freezing temperature.
• Water temperature (max/min): 5 ºC / 60 ºC
• Water pressure (max/min): 1 bar / 3 bar
• This equipment must be connected to the water
main.
• lf the domestic cold water entry pressure is higher
than the equipment's design pressure (10 bar), a
pressure reducer must be fitted with a nominal value
of 7 bar.
EN
PMML0578 rev.0 - 04/2022
!
CAUTION
Do not pass cables through the ventilation hole.
!
DANGER
Pressure Vessel and Safety Device: This heat pump is equipped
with a high pressure vessel under PED (Pressure Equipment
Directive). The pressure vessel has been designed and tested
before shipment according to PED. Also, in order to prevent the
system from an abnormal pressure, a high pressure switch,
which needs no field adjustment, is utilized in the refrigeration
system. Therefore, this heat pump is protected from abnormal
pressures. However, if abnormally high pressure is applied to
the refrigeration cycle including the high pressure vessel(s),
it will result in serious injury or death due to explosion of
the pressure vessel. Do not apply a pressure higher than the
following pressure to the system, by modifying or changing the
high pressure switch.
!
CAUTION
This unit is designed for commercial and light industrial
application. If installed in house hold appliance, it could cause
electromagnetic interference.
Start-up and Operation: Check to ensure that all the
stop valves are fully opened and no obstacle exists at
the inlet/outlet sides before start-up and during the
operation.
Maintenance: Periodically check the high pressure side
pressure. If the pressure is higher than the maximum
allowable pressure, stop the system and clean the heat
exchanger or remove the cause.
Maximum Allowable Pressure and High Pressure
Cut-out Value:
Maximum
Refrigerant
Allowable Pressure
(MPa)
R32
4.15
NOTE
The label for the vessel under PED are attached on the high
pressure vessel. The pressure vessel capacity and vessel category
are indicated on the vessel.
Ventilation hole
High Pressure
Switch Cut-out
Value (MPa)
4.00 ~ 4.10
2