Pressure Gauge; Expansion Vessel; Pump Specifications; Circulating Pump - Vaillant ecoMAX SERIES Instructions For Installation And Servicing

3.11.4 Pressure gauge

This is factory fitted to the boiler and indicates the pri-
mary circuit pressure to facilitate filling and testing.

3.11.5 Expansion vessel

ecoMAX boilers incorporate a 10 litre expansion vessel
which is suitable for a sealed heating system with a
maximum water content of 100 litres.
If the nominal capacity of the built in expansion vessel is
not sufficient for the heating system (for instance in
case of modernization of old open systems) an additio-
nal expansion vessel can be installed external to the boi-
ler. It should be fitted in the return pipe as close as pos-
sible to the boiler in accordance with BS 5449: Part 1.
Guidance on the sizing of an additional expansion vessel
is given in Table 3.4.
Initial system pressure (bar)
Pressure relief valve setting (bar)
Total water content of system litres
25
50
100
125
150
175
200
225
250
275
300
325
350
375
400
425
450
475
500
For system volumes other than those
given above, multiply the
system volume by the factor across
Table 3.4 Sizing of additional expansion vessel
Instructions for installation and servicing ecoMAX
Vessel Volume [L]
1.0 1.5
3.0
2.7 3.9
5.4 7.8
10.9 15.6
13.6 19.5
16.3 23.4
19.1 27.3
21.8 31.2
24.5 35.1
27.2 39.0
30.0 42.9
32.7 46.8
35.7 50.7
38.1 54.6
40.9 58.5
43.6 62.4
46.3 66.3
49.0 70.2
51.8 74.1
54.5 78.0
0.109 0.156
General requirements 3

3.12 Pump specifications

3.12.1 Circulating pump

The circulating pump is included in the boiler. The pump
head available for the heating system is shown in fig. 3.9.
Circulating pump (ecoMAX 635 and 835 only):
The ecoMAX 635 and 835 boilers are fitted with a modu-
lating circulating pump. The pump head available for the
heating system is shown in figure 3.10.
400
300
200
Position II
100
0
0 200 400 600
Fig. 3.9 Pump specifications ecoMAX 613/2, 618/2, 622/2,
824/2, 828/2
400
300
200
53 %
100
0
0 200 400 600
Fig. 3.10 Pump specifications ecoMAX 635, 835
3.12.2 System by–pass
An automatic system by–pass is included within the boi-
ler. The boiler is suitable for use in systems with ther-
mostatic radiator valves and no additional by–pass is
required.

3.12.3 Venting

The boiler is fitted with an automatic air vent. Additional
provision should be made to enable the heating system
to be vented during filling and commissioning either by
automatic air vents or manually.

3.13 Condensate trap

The boiler is fitted with a condensate trap incorporating
a water trap of 75 mm.
Position III
800 1000 1200 1400 1600
Volumeflow [ l/h ]
85 %
70 %
60 %
800 1000 1200 1400 1600 1800
Volumeflow [ l/h ]
1800
100 %
1900
15 15