Grant Vortex VTXBH15/26 User Manual

Section 4: Installation Page 15
UNDERFLOOR:
• Flow temperature 50°C
• Return temperature 40°C
• Di󰀨erential 10°C
In underoor systems, it is essential that the return temperature
must be maintained at or above 40°C to prevent internal corrosion
of the boiler water jacket.
Refer to Section 2.4 for the size and type of the connections and
Section 5 for the position of the connections.
OPEN VENTED SYSTEMS:
! NOTE !
The presence of ‘pumping over’ in an open vented heating
system connected to the Grant Vortex boiler will invalidate
the product guarantee.
Open vented systems must be correctly designed and installed.
The open safety vent pipe must be positioned to prevent ‘pumping
over’ (i.e. the discharge of water from the open safety vent pipe
into the feed and expansion cistern under the pressure created by
the circulator). For detailed information on the correct design of
open vented heating systems, and the correct location of the open
safety vent pipe, refer to the CIBSE Domestic Heating Design
Guide and OFTEC Technical Book 4 (Installation).
4.5 PIPEWORK MATERIALS
The Grant Vortex boiler is compatible with both copper and plastic
pipe. Where plastic pipe is used it must be of the oxygen barrier
type and be the correct class (to BS 7291-1) for the application
concerned.
On either sealed or open-vented systems; where plastic pipe is
used a minimum of ONE metre of copper pipe (or as per pipe
manufacturers instructions) MUST be connected between both
the boiler ow and return connections and the plastic pipe.
! NOTE !
Do not connect plastic pipe directly to the boiler.
Grant UK does not accept any responsibility for any damage,
however caused, to plastic piping or ttings.
SEALED SYSTEMS
If plastic pipe is to be used, the installer must check with the
plastic pipe manufacturer that the pipe to be used is suitable for
the temperature and pressures concerned.
Plastic pipe must be Class S to BS 7291-1.
! WARNING !
When plastic pipe is used, the system MUST incorporate
a low pressure switch to shut o󰀨 power to the boiler if
the system pressure drops below 0.2 bar. A suitable low
pressure switch kit is available to purchase from Grant UK
(product code: MPCBS62).
UNDERFLOOR PIPEWORK
Plastic pipe may be used on underoor oor systems where the
plastic pipe is tted after the thermostatic mixing valve. Copper
tube must be used for at least the rst metre of ow and return
primary pipework between the boiler and the underoor mixing/
blending valves.
4.6 CONNECTIONS
4.6.1 FLOW AND RETURN CONNECTIONS
Refer to Section 5.
4.6.2 CONDENSATE CONNECTION
The condensate trap is supplied loose in the burner box and
needs to be tted as shown in Figure 6-2.
Refer to Section 6 for details of the condensate disposal pipework.
4.6.3 DRAIN COCK
A drain cock is supplied in the accessories pack and should be
tted at the bottom on the front of the boiler to allow the boiler to
be drained.
To enable draining of the system, a suitable drain cock must be
tted at the lowest point of the heating system.
4.7 PREPARATION FOR INSTALLATION
1. Grant Vortex Boiler House models are supplied in two
separate cartons; one containing the boiler and the other
containing the burner and condensate drain trap. The dual
thermostat (15-26 and 26-46 models) is also included with
the burner.
The dual thermostat is factory tted on the 46-70 models.
The ow pipe and push t connector are supplied with the
26-46 model (under the removable cover).
2. Carefully remove the packaging from the boiler and unpack
the carton containing the remaining items.
4.8 INSTALLING THE BOILER
1. Having decided upon the position of the boiler and type of
ue, prepare the wall as described in Section 9. Ensure
that the ue terminal position complies with the necessary
clearances.
2. Make the water connections as described in Section 5. If
access will be restricted, make any connections to the boiler
before placing it in its nal position. Refer to Section 7 if the
boiler is to be used on a sealed system.
! NOTE !
If using a balanced ue system - install the balanced ue
system before connecting the heating system pipework to
the boiler. Once the ue system is tted then complete the
water connections and ll the heating system.
3. Ensure the requirements are met for the disposal of
condensate as described in Section 6.
4. Connect the power supply as described in Section 8.
5. Connect the ue and ensure there is an adequate air supply
as described in Section 9.
4.9 FILLING THE HEATING SYSTEM
Refer to Section 7.2 (Filling the Sealed System)

Grant Vortex VTXBH15/26 Specifications

General

Brand	Grant
Model	Vortex VTXBH15/26
Category	Boiler
Language	English