Condensate Pipework; Internal Connections - Benchmark 27i System Compact Installation, Commissioning And Servicing Instructions

PRE-INSTALLATION
AVAILABLE PUMP HEAD
In order to save as much energy as possible and the
minimise the possibility of water circulation noise, a low
characteristic should be chosen.
The pump map can be selected within 2.1C in the Boiler settings menu
list:
• 0 (pump variable speed setting)
• 1 (constant pressure low)
• 2 (constant pressure low/middle)
• 3 (constant pressure middle/high)
• 4 (constant pressure high)
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0 200 400 600
The factory setting is:
4 (constant pressure high)
CONSTANT PRESSURE HEAD
If the constant pressure head option (1 - 4) is chosen, the differential
pressure between the CH flow and return will be kept at the
corresponding value. When the CH system is cold and the radiator TRVs
are fully open, the pump will be running faster to try and maintain the
pressure differential. When the TRVs start to close and the resistance of
the CH system increases, the pump speed reduces to maintain the
pressure.
The setting (1 - 4) to be selected is dependent upon the resistance and
heat load of the CH system. The higher these are, the higher the pressure
constant
4.4

CONDENSATE PIPEWORK

NOTICE:
▶ Where a new or replacement boiler is being installed,
access to an internal "gravity discharge" point should
be one of the factors considered in determining boiler
location.
▶ The condensate pipe must be nominally
22mm Ø plastic pipe.
▶ The condensate pipework must fall at least 52mm per
metre towards the outlet and should take the shortest
practicable route.
▶ Ensure there are no blockages in the pipe run.
Key to condensate illustrations
1 Condensate discharge from boiler
2 Soil and vent stack
3 Minimum 450mm and up to three storeys
4 Visible air break at plug hole
5 Sink or basin with integrated overflow
6 75mm sink waste trap
7 Condensate pump
* Condensate trap of 75mm already incorporated into the boiler
14
4
3
2
1
800 1000 1200 1400
Flow Rate (l/hr)
6720813276-13.1Wo

4.4.1 INTERNAL CONNECTIONS

In order to minimise risk of freezing during prolonged cold spells, the
following methods of installing condensate drainage pipe should be
adopted, in order of priority.
Wherever possible, the condensate drainage pipe should be routed and
terminated so that the condensate drains away from the boiler under
gravity to a suitable internal foul water discharge point such as an
internal soil and vent stack. A suitable permanent connection to the foul
waste pipe should be used.
1
22mm Ø
1600
Fig. 4 Disposal to soil vent stack
Alternatively if the first option is not possible an internal kitchen or
bathroom waste pipe, washing machine waste pipe etc. can be used.
Ensure that the condensate drain pipe is connected "down stream" of
the waste trap.
1
22mm Ø
Fig. 5 Disposal to a waste pipe
Greenstar i System Compact
2
3
4
100mm
5
75mm
min.
6
ErP - 6 720 813 280 (2015/07)