Heat pump water heater – TECHNICAL INFORMATION FOR INSTALLERS
4.7 Hydraulic connections
Before using the product, we recommend filling its tank with water and draining it completely so as to remove the
residual impurities.
Connect the water heater inlet and outlet to pipes or pipe fittings that can withstand the operating pressure and
temperature of the hot water, which may reach 75 °C. It is not advisable to use materials that cannot withstand such
temperatures. The two dielectric couplings (supplied with the product) must be applied to the inlet and outlet
water pipes, prior to perform the connection.
Screw a "T" fitting identified by a blue collar onto the appliance's water inlet pipe. It is mandatory to screw on said
fitting a cock for draining the product with a tool on one side, and a suitable device against overpressure on the other
side.
BEWARE! It is mandatory to fit a safety valve onto the appliance's water inlet
pipe.
In countries which acknowledge EN 1487 It is mandatory to fit a safety valve
onto the appliance's water inlet pipe. The device must comply with the EN
1487:2002 standard and must have a maximum pressure of 0.7 Mpa (7 bar).
Moreover, it must at least include the following components: a cut-off valve, a
non-return valve, a control mechanism for the non-return valve, a safety valve
and a water pressure shut-off device.
The accessory part codes are:
1/2" hydraulic safety device (for products with 1/2" diameter inlet pipe) ' code 877084;
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3/4" hydraulic safety device (for products with 3/4" diameter inlet pipe) ' code 877085;
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Syphon 1" ' code 877086.
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Some countries may require the use of alternative safety devices, as required by local law; the installer must check
the suitability of the safety device he tends to use. Do not install any shut-off device (valve, cock, etc.) between the
safety device and the heater itself.
The device's relief outlet must be connected to a relief pipe with a diameter no less than that of the appliance's
connection (1/2"), with the aid of a siphon creating an air gap of at least 20 mm to allow for visual inspection; this is to
prevent any harm to persons and animals or damage to objects should the device activate and for which the
manufacturer shall not be held liable. Use a flexible pipe to connect the pressure safety device inlet to the cold water
system pipe, using a cut-off valve if necessary. Additionally, a water discharge pipe must be fitted to the outlet in case
the drainage tap is opened.
Avoid overtightening the pressure safety device and do not tamper with it. It is normal for water to trickle from the
pressure safety device during the heating phase; for this reason, it is necessary to connect the outlet, which must
always be left exposed to the atmosphere, to a drainage pipe that slopes downwards and towards an area not subject
to frost. It is advisable to also connect the condensate outlet to the same pipe, through the connection located on the
lower side of the water heater.
The appliance must not operate with water hardness levels below 12 °F; on the other hand, it is advisable to use a
suitably calibrated and monitored water softener in the event of particularly hard water (>25 °F); in this event, the
residual hardness must not fall below 15 °F.
If the mains pressure is close to the calibrated valve values, a pressure reducer must be installed as far as possible
from the appliance.
FIG 10. Caption: A:hot water outlet pipe / B: cold water inlet pipe / C: safety assembly / D: interception tap / E:
dielectric couplings (apply on inlet and outlet water pipes).
WARNING! It is advisable to carefully wash the system's pipes in order to remove any residues of screw thread,
welding or dirt which may hamper the correct operation of the appliance.
5. INITIAL START-UP
Once the appliance is connected to the hydraulic and electric systems, the water heater must be filled with water from
the domestic water supply network. In order to fill the water heater, it is necessary to open the central tap of the
domestic network supply and the nearest hot water tap, while making sure that all the air in the tank is gradually
expelled.
Visually inspect for possible water leaks from the flange and pipe fittings and gently tighten them, if necessary.
After verifying that there is no presence of water on electrical parts, connect the product to the mains.
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