Baxi Assure FGHR User manual

United Kingdom
en
Fitting Instructions
Assure FGHR

2
The Assure FGHR unit is approved for use with the
following boiler models:-
Baxi Assure Combi
Baxi Assure System
Baxi 600 Combi
Baxi 600 System
Baxi 800 Combi
Baxi 800 System
Baxi Assure 500-2 Combi
Baxi Assure 500-2 System
Baxi 600-2 Combi
Baxi 600-2 System
Baxi 800-2 Combi
Baxi 800-2 System
Contents
Section Page
1.0 Introduction 3
2.0 Introduction 4
3.0 Introduction 5
4.0 Introduction 6
5.0 Introduction 11
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and civil claims for damages.

3
1.0 Introduction
1.1 Description
1. The Assure FGHR is a Passive Flue Gas Heat Recovery
Device as listed in the Government’s Product Characteristics
Database (PCDB).
2. The Assure FGHR uses heat from the ue gases to
pre-heat incoming cold mains water, thus reducing gas
consumption during the production of Domestic Hot
Water.
3. The ue can be to the rear or vertical.
1.2 Contents of pack (Fig. 1)
The pack contains:
i) Assure FGHR
ii) Wall Frame (incorporates boiler
wall bracket)
iii) Collar - Rear Flue
vi) Wall Fixing Screws Pack
v) Template
vi) Literature
vii) SAP Label for Boiler
viii) Inlet & Flow Pipes
1.3 Flues
1. To ensure full boiler output the following equivalent ue
length should not be exceeded:-
all models - 3 metres
Consult the boiler instructions for details of the equivalent
values of any bends.
2. The 60/100 concentric horizontal or vertical ue system
(Flue Group A) approved for the boilers listed on p. 2
MUST be used.
3. Flue kits 5118576 (Vertical), 7210434 (Horizontal Direct
Rear), 720642701, 720598701 & 720599401 (Horizontal
Rear with Elbow - black, brown & white) are compatible.
4. The Assure FGHR MUST NOT be used with the 80/125
ue system or Plume Displacement Kits. Where pluming
may cause a nuisance it is permissible to use Flue Terminal
Deector part no. 5111068 (Black), 720644201 (White) or
720644301 (Brown).
5. If the installation is at a height of more than 18 metres the
direct rear ue MUST NOT BE USED. The following ‘high
rise’ ues are compatible with these installations:
7778067 Horizontal Flue 1.8m A/S
7743932 Horizontal Flue 685mm A/S
7778230 Flue Extension 2m A/S
1.4 Accessories
In accordance with Water Authority Regulations to prevent
backow into the water supply the following item should be
employed and is available as an accessory:
Expansion Vessel & Check Valve Kit 720066401
Other accessories:
Internal Fitting Kit 7215374
IFOS (In Flue Outdoor Sensor) 7724181
i) ii)
iii)
iv)
vii)
v)
vi)
viii)
Fig. 1

4
2.0 Technical Data
DHW Circuit bar
Pressures
Max Inlet - 3*
Min Operating - 0.2
*if required t a pressure reducing
device to achieve this
DHW Circuit l/min
Flow Rates
Max Flow Rate - up to 15*
(*depending on boiler model)
Min Flow Rate - 2.5
Connections stainless steel
Cold Water Mains Inlet - 15 mm
Pre-heated Mains Outlet - 15 mm
Dimensions (Fig. 2) mm
Casing Height - 345 mm
Casing Width - 390 mm
Casing Depth - 280 mm
Flue Centre to Wall - 107 mm
Weights kg
Packed Weight - 14.5 kg
Installation Lift Weight - 12.0 kg
Weight - Full - 19.5 kg
Clearances mm
Above Casing - 175 mm
Below Casing - 50 mm
Front (For Inspection) - 450 mm Min
Front (In Operation) - 5 mm Min
L.H. Side - 5 mm
R.H. Side - 5 mm
General
DHW H/Exch. - Stainless Steel
Flue Connection - Stainless Steel
Casing - White Paint - Steel
Mains Storage Capacity - 7.0 litres
Heat Exchanger - 0.5 litres
Maximum Water Temperature - 60 °C
107 mm
345 mm
195 mm
390 mm
280 mm
Serial No. Position
Distance from Top
Edge of Lower Plate
to Flue Hole Positions
(rear ue options)
Fig. 2
Fig. 3
481 mm
314 mm

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3.0 Important Information & Operation
3.1 Important Information
1. The Assure FGHR must only be tted with one of the
range of boilers specied (see p.2). It must be installed in
accordance with these instructions, and by a competent
person.
2. The current Gas Safety (Installation & Use) Regulations
must be observed, along with all relevant Building
Regulations/Standards, Water Regulations/Standards and
the B.S. Codes of Practice listed in the boiler instructions.
3. A dedicated wall frame (Section 1.2, item ii) is supplied
to mount the Assure FGHR and boiler on - this MUST be
used and tted in accordance with these instructions and
as shown on the template supplied.
4. When installing direct rear ue 7210434 the collar
(Section 1.2, item iii) must also be used and the hole for
the ue must be cut Ø150 mm. Also Internal Fitting Kit
7215374 should be acquired and the foam seal from this
kit employed.
5. The Assure FGHR must be tted on a at vertical
surface.
6. The Assure FGHR is in eect part of the ue system
and should be considered as such.
IMPORTANT: These instructions must be read in
conjunction with those supplied with the boiler.
3.2 Operation
1. There are no moving parts in the Assure FGHR and it
does not need any electrical supply. It is connects to the
boiler ue adaptor and is mounted on a special wall frame
on which the boiler is also hung.
2. A gas-to-water heat exchanger extracts heat from the
discharged products of combustion (hot ue gases) during
boiler operation. This heat is used to pre-heat the
incoming cold mains before it is heated for domestic hot
water purposes.
3. In central heating mode the cylinder captures the heat
from the hot ue gases which is stored for later use.
4. Additionally, as the ue gases leaving the Assure FGHR
contain considerably less moisture, the amount of pluming
is reduced.

6
4.0 Installation
4.1 Installation - Pipe Assembly
1. It is essential that the pipes supplied are identied
correctly & joined and connected accordingly (Fig. 4):
• Pipe A - DHW Upper Pipe
• Pipe B1 - DHW Lower Pipe (see table 1 for boiler
applications)
• Pipe B2 - DHW Lower Pipe (see table 1 for boiler
applications)
Note: Pipe B2 is 13 mm longer than B1
• Pipe C - Mains In Upper Pipe
• Pipe D - Mains In Lower Pipe
2. Pipes A & C connect to the Assure FGHR unit.
Pipe B1 or B2 connects to the cold water inlet.
Pipe D connects to mains cold water.
3. Before soldering Pipe A to B1 or B2 and Pipe C to D
ensure that the nuts are tted to A and C.
4. Note the identifying indentations in Pipes C & D - Pipe
A must not be connected to Pipe D. Pipes B1 & B2 are
identied by a label.
5. Ensure that the horizontal legs of Pipes A & B1 or B2 are
oset slightly as illustrated (when viewed from above)
before soldering (Fig. 5).
6. An oset of 3° ensures that Pipe B1 or B2 will connect
correctly to the cold inlet tap and allow Pipe A to clear
the boiler adaptor.
B1
CA
D
Mains Cold Water
To Combi Cold Water Inlet
C & D identifying
indentations
B2
B1 & B2 identifying
labels
B1 or
B2
A
Offset pipes by 3°
Pipe Identication Fig. 4
Pipes A & B1 or B2 oset
Fig. 5
Table 1
Pipe B1 must be used on:
Baxi Assure Combi
Baxi 600 Combi
Baxi 800 Combi
Pipe B2 must be used on:
Baxi Assure 500-2 Combi
Baxi 600-2 Combi
Baxi 800-2 Combi

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4.0 Installation
4.1 Installation - Pipe Assembly (cont.)
7. When installing the Assure FGHR in conjunction with
a System boiler the lower pipes, B1, B2 & D, may be
dispensed with and the upper pipes, A & C, shortened.
8. An example of shortening pipes A & C is shown in
Fig. 6. The characteristics of each installation, position of
existing pipework etc. will inuence how much pipes can
be shortened.
9. See Figs. 7 & 8 for dimensions that will assist when
shortening pipes A & C and routing of system pipework.
NOTE: The illustrations in Sections 4.2, 4.3 & 4.4 show
the full pipe assemblies.
CA
Pipe Shortening Examples
System Boiler Applications
Fig. 6
120 mm
75 mm
235 mm
55 mm
Fig. 7
Fig. 8
View from side
View from front

8
4.0 Installation
4.2 Installation - Vertical Flue 5118576
IMPORTANT: Follow the Installation & Servicing
Instructions supplied with the boiler to the point at
which the wall plate is tted, but do not mark the ue
position. The Assure FGHR must be tted on a at
vertical surface.
1. Align the Assure FGHR template on the wall (Fig. 9)
and mark the positions of suitable xing points on the
upper and lower plates of the wall frame.
2. Drill & plug the xing points, secure the frame and hang
the boiler on the lower plate (Fig. 10). Prime the boiler
trap by pouring 300 ml of clean cold water into the
central spigot. Do not allow any water to spill into the
air chamber.
3. After identifying the FGHR inlet and ow pipes
(Fig. 11 ), manoeuvre them into place behind the boiler.
4. Undo the screws securing the top ue adaptor and
remove the adaptor. Retain the screws & adaptor for reuse.
Extract the blanking cap and discard, recycling where
possible. Ret the adaptor and secure with the screws
previously removed (Fig. 12).
5. The Assure FGHR can now be tted (Figs. 13 & 14).
Locate the slots in the rear on the upper plate and ue
connection on the underside of the Assure FGHR in the
boiler adaptor, taking care to not displace the seals.
6. The ue system can now be installed (Fig. 15). The ue
adaptor on top of the Assure FGHR is similar to that on
the boiler.
7. Connect the ow & inlet pipes to the ttings on the
underside of the FGHR unit ensuring that the sealing
washers are in place.
8. Continue with the installation and commissioning of
the boiler.
Rear Flue - Drill Hole Ø125mm
Upper Plate
Lower Plate
Fig. 9
Template
Upper Plate
Lower Plate
Priming
Fig. 10
1 3
2
1
2
Flow Pipe
Inlet Pipe
Fig. 11
Fig. 12
Fig. 13 Fig. 14
Fig. 15
Vertical Flue
tted to FGHR

9
4.0 Installation
4.3 Installation - Horizontal Direct Rear Flue
7210434
IMPORTANT: Follow the Installation & Servicing
Instructions supplied with the boiler to the point at
which the wall plate is tted, but do not mark the ue
position. The Assure FGHR must be tted on a at
vertical surface.
1. Align the Assure FGHR template on the wall (Fig. 16)
and mark the positions of suitable xing points on the
upper and lower plates of the wall frame.
2. Drill & plug the xing points. Cut the hole for the ue
Ø150 mm. Measure the wall thickness and add 17 mm.
Adjust the telescopic ue to length after locating and
securing it in the sliding collar with the screws supplied.
Tape and secure the ue (Fig. 17).
3. Apply the self-adhesive foam from kit 7215374 to the
rear face of the sliding collar (Fig. 18). Wrap the foam
around the ue twice. Engage the ue & collar in the
channels on the frame (Fig. 19).
4. Insert the ue into the Ø150 mm hole and secure the
frame assembly to the wall, ensuring the ue is uppermost
in the hole by pushing up the sliding collar. Hang the boiler
on the lower plate (Fig. 20). Prime the boiler trap by
pouring 300 ml of clean cold water into the central spigot.
Do not allow any water to spill into the air chamber.
5. After identifying the FGHR inlet and ow pipes (Fig. 21),
manoeuvre them into place behind the boiler.
6. Undo the screws securing the rear ue adaptor and
remove the adaptor. Retain the screws & adaptor for reuse.
Extract the blanking cap and discard, recycling where
possible. Ret the adaptor and secure with the screws
previously removed (Fig. 22).
7. The Assure FGHR can now be tted (Fig. 23). Locate
the slots in the rear of the FGHR on the tabs of the
ue collar & upper plate. Lower the FGHR to engage
the ue connection on the underside with the boiler
adaptor, taking care to not displace the seals.
8. As the FGHR is lowered the ue & collar assembly
will slide down the channels to the lowest position.
9. Connect the ow & inlet pipes to the ttings on the
underside of the FGHR unit ensuring that the sealing
washers are in place.
10. Continue with the installation and commissioning of
the boiler.
Rear Flue - Drill Hole Ø125mm
Upper Plate
Lower Plate
Fig. 16
Template
Upper Plate
Lower Plate
Fig. 17
Wall
Thickness
+17 mm
Flue in Sliding
Collar
Wall Thickness +17 mm
Foam Seal
Fig. 18
Fig. 19
Fig. 20
Fig. 21
1
3
2
1
2
Flow Pipe
Inlet
Pipe
Keep Flue
Uppermost in
Hole
Priming
Fig. 22
Fig. 23
Locate Slots in
FGHR on Tabs
Direct Rear Flue
tted to FGHR

10
4.0 Installation
4.4 Installation - Horizontal Rear Flues with Elbow
720642701, 720598701 & 720599401
IMPORTANT: Follow the Installation & Servicing
Instructions supplied with the boiler to the point at
which the wall plate is tted, but do not mark the ue
position. The Assure FGHR must be tted on a at
vertical surface.
1. Align the Assure FGHR template on the wall (Fig. 24)
and mark the positions of suitable xing points on the
upper and lower plates of the wall frame.
2. Drill & plug the xing points and cut the hole for the ue
Ø116 mm. Secure the frame and hang the boiler on the
lower plate (Fig. 25). Prime the boiler trap by pouring
300 ml of clean cold water into the central spigot. Do not
allow any water to spill into the air chamber.
3. After identifying the FGHR inlet and ow pipes (Fig. 26),
manoeuvre them into place behind the boiler.
4. Undo the screws securing the top ue adaptor and
remove the adaptor. Retain the screws & adaptor for re-
use. Extract the blanking cap and discard, recycling where
possible. Ret the adaptor and secure with the screws
previously removed (Fig. 27).
5. The Assure FGHR can now be tted (Figs. 28 & 29).
Locate the slots in the rear on the upper plate and ue
connection on the underside of the Assure FGHR in the
boiler adaptor, taking care to not displace the seals.
6. The ue system can now be installed (Fig. 30). Follow the
method described in the boiler Installation & Service Manual.
The ue adaptor on top of the Assure FGHR is similar to
that on the boiler.
7. Connect the ow & inlet pipes to the ttings on the
underside of the FGHR unit ensuring that the sealing
washers are in place.
8. Continue with the installation and commissioning of the
boiler.
Rear Flue - Drill Hole Ø125mm
Upper Plate
Lower Plate
Fig. 24
Template
Upper Plate
Lower Plate
Priming
Fig. 25
Flow Pipe
Inlet Pipe
Fig. 26
1 3
2
Fig. 27
1
2
Fig. 28 Fig. 29
Fig. 30
Rear Flue with Elbow
tted to FGHR