Vaillant ecoMAX pro 18E, Instructions For Use Installation And Servicing

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Instructions for Use, Installation and Servicing ecoMAX pro
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6.1 Draining Tap
A draining tap must be provided at all the lowest points
of the system, which will allow the entire system and hot
water system to be drained.
Draining taps shall be to the current issue of BS 2879.
6.2 Safety Valve
A safety valve need not be fitted to an open-vented
system. See also section 6.9.1.
6.3 Pump
The pump should be fitted on the flow pipe from the
boiler and have isolating valves each side.
A variable duty pump should be set to give a
temperature difference of no greater than 20°C
between the flow and return, with the thermostat set at
“MAX”, which is about 80°C, to give a flow rate as shown
in table 2.
See chart for pressure loss of the boiler, fig 6.1 or 6.2.
High resistance micro bore systems may require a higher
duty pump.
6.4 Bypass
A system bypass will be required fitted at least 1.5
metres away from the boiler, refer to the current issue of
central heating system specifications (CHeSS).
Fig 6.1
12625
Fig 6.2
12626
6 Water system
Model Minimum flow rate
ecoMAX pro 18 E 773.8 litres/hr
ecoMAX pro 28 E 1289 litres/hr
This is equal to 20°C differential at
maximum heat input.
TABLE 2