Domestic Hot Water System Design; Boiler Schematic - Saunier Duval ISOMAX F 28 E Installation And Operating Instructions Manual

DOMESTIC HOT WATER SYSTEM DESIGN

Copper tubing or plastic Hep
the domestic hot water system. Unnecessary
pressure losses should be avoided.
A flow restrictor limiting the flow through the boiler
to a maximum of 16 l/min is fitted to the boiler.
The boiler will operate with a minimum supply
pressure of 0,7 bar, but under reduced flow rate.
Best operating comfort will be obtained from a sup-
ply pressure of 1 bar.

BOILER SCHEMATIC

1 - Domestic thermistor
2 - Three way valve
3 - Gas valve
4 - Gas valve ignition module
5 - Temperatur sensor for accumulation vessel
6 - Accumulation vessel
7 - Burner
8 - Ignition electrode
9 - Combustion chamber
10 - Heating safety valve (3 bar)
11 - Main heat exchanger
12 - Air pressure switch
13 - Flow detector
14 - DHW pump
15 - Non return valve
16 - Bypass
17 - Domestic heat exchanger
18 - Heating pump
19 - Heating expansion vessel
20 - Heating thermistor
21 - Overheat safety thermostat
22 - Flame sensor electrode
23 - Fan
24 - Domestic safety valve (6 bar)
25 - Loss of water sensor
26 - Domestic expansion vessel
27 - Pressure/temperature relief (7 bar)
28 - Domestic safety valve (10 bar)
A - Heating return
B - Cold water inlet
C - Heating flow
D - Domestic hot water outlet
E - Gas
D1 - Discharge from HTG safety valves
D2 - Discharge from DHW safety valves
D3 - Discharge from temp/press (to tundish)
Valve
Minimum
Minimum
outlet size
size of
size of
discharge
discharge
to tundish
pipe D2
from
tundish
G 1/2 15 mm 22mm
28 mm
35 mm
G 3/4 22 mm 28 mm
35 mm
42 mm
G 1 28 mm 35 mm
42 mm
54 mm
8
0 may be used for
2
19
Maximum Resistance
resistance created by
allowed each elbow or
expressed as a bend
length of
straight pipe
i.e. no elbows
or bends
up to 9 m 0.8 m
up to 18 m 1.0 m
up to 27 m 1.4 m
up to 9 m 1.0 m
up to 18 m 1.4 m
up to 27 m 1.7 m
up to 9 m 1.4 m
up to 18 m 1.7 m
up to 27 m 2.3 m
'Hard Water Areas'
In areas where the water is 'hard', more than
200mg/litre, it is recommended that a proprietary
scale reducer is fitted in the cold water supply to
the boiler.
23
11
21
9
7
22
8
20
18
2
16
17
14
15
25
13
10 28
A B C
D1 D1 D2 D1
Diagram 6
Discharge from HTG+
domestic prv on jig
D2
D1
Diagram 6a
12
27
6
3
4
1
D E
D3 D1
Discharge from DHW
safety valves
D3
Tundish
5
26
24
Gully