Baxi Assure Horizontal SHRU Manual

These instructions are to be left with theuser. The Assure HorizontalSHRU should only be installed by
a competent plumber who has the expertise to be guided by this manual.
Please read the entire manual before commencing the installation process.
Installation and Maintenance Manual
Waste Water Heat Recovery Unit
Assure Horizontal SHRU

2
3Installation Instructions F10-60/170714
Contents
3
4
4
4
5
5
5
1. Introduction
2. Product Technical Data
2.1. Dimensions
2.2. Technical Specifications
3. Pre-installation Requirements
3.1. Principle of Operation
3.2 Installation Configuration
3.3. Requirements for Recognition within SAP Calculations 6
6
6
7
3.3.1. Dwelling Evaluation
3.3.2. Drainage Connections
3.3.3. Plumbing Connections
3.3.4. Installation Location 7
8
8
9
10
12
14
14
15
15
4. Installation
4.1. Package Contents
4.2. Installation Procedure
4.2.1 Installation - Method 1
4.2.2 Installation - Method 2
5. Maintenance
6. Warranty
7. Safety
7.1. Tested for Drinking Water Consumption
8. 7.2. Legionella Prevention 15

3
4Installation Instructions F10-60/170714
1. INTRODUCTION
Thank you for purchasing the Assure Horizontal
SHRU.
This unit allows the heat contained in the shower or
bath waste water to be recovered and transfers this
heat to the cold water before it goes to the shower
mixer tap and/or water heater device.
There is no contact between the water supply and
the drain water.
The transfer of heat is achieved through a double-
walled copper heat exchanger in accordance with
the regulations EN 1717.
When utilizing the Assure Horizontal SHRU, the cold
water feeding into the mixer valve or heater device is
pre-heated to approximately 20 - 25°C, an increase of
approximately 15°C (depending on the type of
configuration and flow of the shower). The result is
a significant energy saving.
IMPORTANT!
Please note that this manual contains important
information, read it carefully before starting the
installation or use of the product.
-Installation and associated work on this
equipment must be carried out by a competent
professional.
-Non-compliance with the recommendations for
installation and use may void any warranty.
-Keep this manual in a safe place for easy
reference when required throughout the life of the
product.
-This product does not have a waste trap. It is a
requirement of the installation to fit an in line trap
upstream from the product itself.
NCM/SAP recognition
For the recognition of the Assure Horizontal SHRU
energy saving performance within the National
Calculation Method (NCM) for energy rating of
dwellings known as SAP
(Standard Assessment Procedure) it is vital to
comply with the following:
a) This instruction manual
b) The System Design Checklist
c) The Installation Checklist
d) The Certificate of Installation
b, c & d are supplied as a single document and
are available at: www.ncm-pcdb.or-g.uk/sap
(under ‘Technical Documents’). A signed copy
of each should:
1. Be left with the user pack
2. Retained by the installer
3. A copy sent to Baxi (See company details on
Page 16).
(Note: Building control officers may also request a
copy)
A NCM (SAP) identifier label is permanently fixed
to the Assure Horizontal SHRU unit and a second
label attached to a nearby boiler or service
cupboard. The ‘model qualifier’ denotes the system
installation configuration System A, B or C. For the
permanent label, the model qualifier will state
“Refer to installation certificate, if unknown assume
System B”. The actual system configuration will be
recorded on the system design checklist,
installation checklist/ certificate of installation and
the second NCM (SAP) identifier label.

4
5Installation Instructions F10-60/170714
2. PRODUCT TECHNICAL DATA
2.1. Dimensions (in millimetres)
2.2. Technical Specification
Unit ValueDescription
Heat exchanger material - copper
Body material - ABS
Weight kg 5.0
Temperature range ºC 0 - 60
L/min 25.0
Maximum mains water inlet pressure Bar 6.0
Heat exchanger pressure drop at 9.2 L/min —
mains water Bar 0.36
Heat exchanger pressure drop at 12.5 L/min —
mains water Bar 0.65
130
96
540
53
487
456 84
M 1/2"
M 1/2"
90
0-20
Ø40
83 428 29
25
46
Maximum shower flow

5
6Installation Instructions F10-60/170714
2.3. Performance
Shower Flow
Rate at 40ºC
System A System B System C
Recovered
Energy
Recovered
Energy
Recovered
Energy
9.0 L/m 23.9% 4.48 kWh 20.2% - 22.7% -
9.2 L/m 23.6% 4.56 kWh - - - -
11.0 L/m 22.4% 5.22 kWh 19.30% - 21.2% -
12.5 L/m 21.8% 5.72 kWh - - - -
3. PRE-INSTALLATION REQUIREMENTS
3.1. Principle of Operation
The Assure Horizontal SHRU is a Waste Water Heat Recovery Unit (WWHRU).
The Assure Horizontal SHRU recovers the heat contained in the shower/bath drain water and transfers this heat
to the cold mains water prior to reaching the shower mixer tap and/or Domestic Hot Water heater (DHW). The
DHW heater could be a combination boiler, an unvented cylinder, a heat interface unit on a district heating
scheme* or a thermal store.*
(*) mains pressure DHW delivery
The Assure Horizontal SHRU must be located horizontally on a suitable base below the shower/bath, with the
desired separation.
The mains cold water is connected to the Assure Horizontal SHRU inlet and the preheated water from the Assure
Horizontal SHRU is connected in one of the following 3 configurations
System A: To the shower mixing valve (mains cold water) inlet and the DHW heater inlet. This will
provide the maximum amount of recovered energy.
System B: To the shower mixing valve (mains cold water) inlet ONLY. We recommend this
configuration if the connection to the DHW heater involves too much work or it is too far.
System C: To the DHW heater inlet ONLY.
SAP calculation recognises the performances of Systems A, B & C. System A will provide the highest
efficiencies (see section 2.3 for different system performances). Note kWh calculations are estimates
and are not calculated by SAP.
gency KIWA Nederland B.V.
3.2. Installation Configuration

6
7Installation Instructions F10-60/170714
3.3. Requirements for Recognition within SAP Calculations
3.3.1. Dwelling Evaluation
3.3.2. Drainage Connections
The following dwelling requirements must be satisfied in order for the WWHRS to be recognised in
SAP calculations:
• Supply water pressure and flow rate must be sufficient to ensure satisfactory DHW
performance after installation of the Assure Horizontal SHRU.
•
•
The domestic hot water system (DHW) must be a mains pressure system;
If not installed in System B configuration, the DHW heater must accept a
pre-heated water inlet (Max. 30°C).
•The shower(s) must use a thermostatic mixing valves.
•The Assure Horizontal SHRU must be installed within the dwelling heated envelope.
NOTE: Whilst the Assure Horizontal SHRU can be connected to instantaneous electric
showers, such combinations are not recognised in SAP calculations.
The length of the drain pipe between the shower and the Assure Horizontal SHRU must be minimised,
preferably to less than 3 metres.
With reference to Approved Document – Part H (2002) of the Building Regulations, an appropriate
method for preventing the ingress of foul sewer gases as a result of the WWHRS installation must be
devised. An aeration valve is not required.

7
8Installation Instructions F10-60/170714
3.3.3. Plumbing Connections
The pipework between the Assure Horizontal SHRU preheated water outlet and the water heater and/or shower
cold water inlet(s) (depending on installation configuration) must be:
•Labelled to indicate that no other services can be interconnected, to prevent the future
connection of any other service points, such as taps.
•Insulated in accordance with the specification for DHW primary circulation pipes
defined in ‘Domestic Building Services Compliance Guide - 2013 Edition’.
•The WWHRS preheated water outlet is only connected to the water heater and shower cold
water inlet(s), but not any other service points, such as taps.
•If shut-off valves are specified for the Assure Horizontal SHRU inlet and/or outlet, they must
be of the ‘full flow’ (non-restricting) type.
3.3.4. Installation Location
The location must allow access to all parts and easily allow any maintenance, such as cleaning. The
installation location for the Assure Horizontal SHRU should not normally exceed 25°C. The Assure
Horizontal SHRU installation should ensure compliance with Approved Document Part H (2002) of the
Building Regulations.
4. INSTALLATION
4.1. Package contents
1
23
4
5
5

8
8Installation Instructions F10-60/170714
3.3.3. Plumbing Connections
The pipework between the Megaflo Horizontal SHRU iZi preheated water outlet and the water heater
and/or shower cold water inlet(s) (depending on installation configuration) must be:
• Labelled to indicate that no other services can be interconnected, to prevent the future
connection of any other service points, such as taps;
• Insulated in accordance with the specification for DHW primary circulation pipes
defined in ‘Domestic Building Services Compliance Guide - 2013 Edition’.
• The WWHRS preheated water outlet is only connected to the water heater and shower
cold water inlet(s), but not any other service points, such as taps.
• If shut-off valves are specified for the Megaflo Horizontal SHRU iZi unit inlet and/or outlet,
they must be ‘full flow’ (non-restricting) shut-off valves.
3.3.4. Installation Location
The location must allow access to all parts and easily allow any maintenance, such as cleaning.
The installation location for the Megaflo Horizontal SHRU iZi should not normally exceed 25°C.
The Megaflo Horizontal SHRU iZi installation should ensure compliance with Approved Document
Part H (2002) of the Building Regulations.
4. INSTALLATION
4.1. Package contents
1
23
4
5
5
5
3
2
4
1
5
9Installation Instructions F10-60/170714
Nº Description Material Connection Quantity
1Shower/bath drain water input connection ABS Ø40mm Female 1
2 Shower/bath drain water output connection PVC Ø40mm Male 1
3 Mains water input connection Brass 1/2” Male 1
4 Mains water output connection Brass 1/2” Male 1
5 Adjustable foot Steel/Plastic - 4

9
4.2 TWO METHODS OF INSTALLATION
4.2.1 Installation above the slab / coupled to the shower tray. Page 10-11
4.2.2 Installation under the slab / under the shower tray or bathtub with
desired separation.
Page 12-14

10
EE
SECTION
E-E
α
4.2.1 INSTALLATION - METHOD 1
1
2
3Put the shower tray over the Assure Horizontal SHRU and align it. Remove the
tray for implementing the next steps.
555555
1
2
4
3
!!
Always ensure that the pipe connecting the drain and Assure Horizontal SHRU has
an inclination (α) between 1% and 2%.
Using a spirit level and the adjustable feet (5), adjust the unit’s height and
position it horizontally in its final location. The internal bore of the Assure
Horizontal SHRU already has a slope of 2% to ensure the correct flow of
waste water from the shower.

11
555555
12
4
3
4
5
6
Connect the mains cold water to the unit’s inlet (3), and preheated water outlet
(4) from the unit to the cold side of the shower mixer tap and/or domestic water
heater (depending on installation configuration). Use both of the provided Male
1/2’’ fittings and proceed to seal in accordance with best plumbing practices.
Connect the Assure Horizontal SHRU drain water outlet (2) to the drain pipe.
We recommend that the installer performs a leak test on the mains water circuit
and on the drain water circuit to ensure the integrity of the inlet and outlet
connections.
Assemble the waste trap and shower tray.

12
Ensure that there is enough space for an easy installation of
Assure Horizontal SHRU.
Ø40mm
Install a 90° elbow Ø40mm. Ensure that elbow is fully inserted
past the seal in the unit.
If necessary, use a section of appropriately rated PVC of the
desired length.
4.2.2 INSTALLATION - METHOD 2
1
2
3

13
Using suitable screws, fix the Assure Horizontal SHRU to the slab.
Make sure that the unit is installed horizontally. The internal bore of the
Assure Horizontal SHRU already has a slope of 2% to ensure the correct flow
of waste water from the shower.
Connect the mains cold water to the unit’s inlet (3), and preheated water
outlet (4) from the unit to the cold side of the shower mixer tap and/or
domestic water heater (depending on installation configuration). Use both of
the provided male 1/2’’ fittings and proceed to seal in accordance with best
plumbing practice.
Connect the Assure Horizontal SHRU drain water outlet (2) to the drain pipe.
555555
12
4
3
!!
4
5
6

14
We recommend that the installer performs a leak test on the mains water
circuit and on the drain water circuit to ensure the integrity of the inlet and
outlet connections.
Install the shower tray and the shower waste trap.
Draw_16
WEIGHT:
A3
SHEET 1 OF 1 SCALE:1:10
DWG NO.
TITLE:
REVISION
DO NOT SCALE DRAWING
MATERIAL:
DATE
SIGNATURE
NAME
DEBUR AND
BREAK SHARP
EDGES
FINISH:
UNLESS OTHERWISE SPECIFIED:
DIMENSIONS ARE IN MILLIMETERS
SURFACE FINISH:
TOLERANCES:
LINEAR:
ANGULAR:
Q.A
MFG
APPV'D
CHK'D
DRAWN
5. MAINTENANCE
• Installed with cold inlet pressure above 6 bar.
• Use of the system without a waste trap.
• Inadequate cleaning of the waste trap.
• Installation of the Assure Horizontal SHRU not in accordance with these instructions..
• Unauthorized repairs and modifications.
7
8
The Assure Horizontal SHRU has been designed to require minimal maintenance other than
regular cleaning of traps and filters removing all hair and dirt, thus preventing blockages.
To maintain efficiency it is recommend you periodically dissolve soap residue on the inside
copper pipe with your usual drain cleaner and/or to clean the unit with a pipe cleaning brush
and hot water
6. WARRANTY
The Assure Horizontal SHRU warranty is valid for 2 years after the installation date.
During the warranty period if the product has a defect in design, material or workmanship it
should be returned to the place of purchase.
The warranty will be invalidated if product failures are caused by the following:
To assist with maintenance it is strongly recommended to install a waste trap before the Assure SHRU
to prevent the ingress of material that may diminish the effectiveness of the unit.

15
11Installation Instructions F10-60/170714
The Assure Horizontal SHRU complies with the requirements of the United Kingdom Water Supply
European regulations EN 1717 (“Protection against pollution of potable water in water installations
and general requirements of devices to prevent pollution by backflow”) require that double walls must
be used to separate drain water and drinking water. The copper coil heat exchanger is made by
squeezing two copper pipes against each other. This creates a very robust and consistent structure,
in which the contact between the pipes does not depend on water pressure.
7. SAFETY
7.1. Tested for Drinking Water Consumption
7.2. Legionella Prevention
The Assure Horizontal SHRU design also complies with the Directive Legionella Prevention:
•The unit has no dead spaces and is subject to high flow rates which prevent water from
stagnation.
•Drain water does not remain in the unit for long periods of time since the construction
guarantees that it is fully drained after the shower is turned off.
•After showering, fresh water cools down below 25ºC, as recommended by the WHO.
•The Assure Horizontal SHRU is always installed relatively close to the shower mixer which
minimizes the distance between the unit and waste trap.
•The copper coil itself contributes to reducing Legionella-related risks.

Baxi Customer Support
0344 871 1545
baxi.co.uk
Baxi
Brooks House,
Coventry Road,
Warwick, CV34 4LL
e&oe
All descriptions and illustrations provided in this document have been
carefully prepared but we reserve the right to make changes and
improvements in our products which may affect the accuracy of the
information contained in this leaflet. All goods are sold subject to our
standard Conditions of Sale which are available on request.
7775228-01 (12/20)