3
technical information
Unit Compatibility
Cylinder unit
Outdoor unit
PUHZ-W50-85
Packaged model
PUHZ-HW112-140
PUHZ-RP35-140
PUHZ-HRP71-125
Split model
PUHZ-SW40-120
PUHZ-SHW80-140
PUHZ-FRP
Water circuit diagram
<EHST20C-*M*HB/ *M*B> (Split model system)
10
26
Drain
25
24
1
Flare connections
<EHST20C-VM6SB> (Solar split model system)
32
33
26
Drain
25
24
1
Flare connections
11
EHST20C-
EHST20C-
EHST20C-
VM6HB
YM9HB
VM6B
37
29
Cold water
9
Pa
26
27
Drain
11
28
12
13
23
15
16
14
8
7
M
6
2
21
4
5
3
22
19
18
20
Cylinder unit
<Figure 3.6>
33
37
Cold
29
water
9
10
Pa
26
11
Drain
28
12
13
23
14
7
8
M
6
2
21
4
5
3
22
19
18
20
Cylinder unit
<Figure 3.7>
EHST20C-
EHST20C-
EHST20C-
EHST20C-
YM9B
VM6EB
YM9EB
VM6SB
<Table 3.8>
A
B
DHW
30
Local system
*1
31
30
29
Water
Drain
supply
A
B
DHW
27
30
Local system
*1
31
30
29
Water
Drain
supply
EHPT20X-
EHPT20X-
EHPT20X-
EHPT20X-
VM2HB
VM6HB
YM9HB
VM6B
A.
Refrigerant pipe
B.
Water pipe
1.
Plate heat exchanger
2.
Flexible hose
3.
Booster heater 1,2
4.
Drain cock (booster heater)
5.
Pump valve
6.
Water circulation pump 1
7.
3-way valve
8.
Manual air vent
9.
Manometer
10. Pressure relief valve (3 bar)
11. Automatic air vent
12. Expansion vessel (except EHST20C-*M*EB)
13. DHW tank
14. Drain cock (DHW tank)
15. Flexible hose
16. Immersion heater (only for EH*T20*-*M*HB)
18. Strainer valve
19. Flow switch
20. Drain cock (primary circuit)
21. THW1
22. THW2
23. THW5
24. TH2
25. Outdoor unit
26. Drain pipe (field supply)
27. Cold water inlet pipe
28. DHW outlet connection
29. Back flow prevention device (field supply)
30. Isolating valve (field supply)
31. Magnetic filter (field supply) (recommended)
32. Solar panel (field supply)
33. Solar hydraulic kit (kit to be compatible for use
with FTC 4 (field supply)
37. Pressure relief valve (10 bar) (accessory)
*1 Refer to Page 14.
Note
• To enable draining of the cylinder unit an
isolating valve should be positioned on both
the inlet and outlet pipework. No valve
should be fitted between the pressure relief
valve (item 37) and the cylinder unit (safety
matter).
• Be sure to install a strainer, on the inlet
pipework to the cylinder unit.
• Suitable drain pipework should be attached
to all relief valves in accordance with your
country's regulations.
• A backflow prevention device must be
installed on the cold water supply pipework
(IEC 61770)
• When using components made from
different metals or connecting pipes made
of different metals insulate the joints to
prevent any corrosive reaction taking place
which may damage the pipework.
EHPT20X-
YM9B