Mitsubishi Electric EHWT17D-MHEDW, Справочник данных

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<Figure 7.6.6>
<UK model>
EHWT17D-MHEDW
<Other models>
The expansion vessel on the sanitary water side shall
be installed as necessary in accordance with your lo-
cal regulations.
7.6.5 Safety Device Connections
The expansion relief valve on the secondary hot water side, and the temperature
and pressure (T&P) relief valve (*A), both need appropriate discharge pipework.
There must be no valve fitted between the expansion relief valve and the tank.
*A EHWT17D-MHEDW is equipped with T & P relief valve on the tank (2).
Other models are equipped with Pressure relief valve, fitted to the DHW
pipework (3).
Note : 1. Do not secure the screws excessively when connecting the Discharge
pipe, otherwise it may result in damage to the cylinder unit.
<For UK>
The right side panel has a plate (*B) so that connection can be made to the fac-
tory fitted temperature and pressure relief valve. If you wish to make the connec -
tion in a different position you will have to cut a hole in the side panel yourself.
However it remains necessary that the drainage parameters outlined in the ap-
propriate Building Regulations are complied with.
*B Unscrew the plate on the right-side panel, connect the Pressure relief valve
to the discharge pipework, and refit the plate. Always replace the plate so
that no gaps exist between the plate and side panel and the plate and drain
pipe to avoid heat loss.
In accordance with Building Regulations a tundish must be fitted into the
pipework within 500 mm of the safety device (also see Figure 7.6.7). Due to
the distance between the two safety devices it may be necessary to fit each
safety device with its own tundish before you run the pipework together to a
safe discharge (see Figure 7.6.6).
Note : 2. Alternatively the discharges from the expansion relief valve and
T&P relief valve may commonly discharge to a singular tundish,
so long as this tundish is located within 500 mm of the T&P relief
valve in UK. When connecting discharge pipes to the safety de-
vices, beware not to strain the inlet connections.
Diagram
part No.
Description Connection
size
Connection
type
1
Expansion relief valve
(part of inlet control group)
15 mm Compression
2
T&P relief valve 15 mm /G 1/2 Compression/
Female
3 Pressure relief valve G 1/2 Female
<Table 7.6.3>
For UK use PAC-WK02UK-E kit, for other countries please see below;
• Any discharge pipework should be capable of withstanding discharge of hot
water. Discharge pipework should be installed in a continuously downward
direction. Discharge pipework must be left open to the environment.
Always refer to local regulations when installing discharge pipework.
Install discharge pipework in a frost-free environment.
It is necessary to provide appropriate drainage from the pressure relief
valve situated on top of the cylinder unit to prevent damage to the unit and
the surrounding area from any steam or hot water released. Relief valves
MUST NOT be used for any other purpose.
Cold water inlet
Tundish
DHW
DHW
Cold water inlet
Piping diagram for 2-zone temperature control
Connect the pipe work and locally supplied parts according to the relevant circuit diagram shown in Section 3. Technical Information, of this manual.
For more details on wiring, refer to “7.4.3 Wiring for 2-zone temperature controls”.
Note: Do not install the thermistors on the mixing tank. This could affect correct monitoring of flow and return temperatures through each zone.
Install the Zone2 flow temp. thermistor (THW8) near the mixing valve.
B-230
Water to Water Heat Pump (WTW)
7
Cylinder
unit/
Hydrobox/GSHP/WTW