Baxi MULTIFIT Evacuated Tube Collector Manual

Evacuated Tube Collector
10 Tube Additional Pitched Roof Kit
Kit Part No. 5130243
THESE INSTRUCTIONS CONTAIN INFORMATION FROM THE FOLLOWING BOOKLETS:
Baxi SolarfloTM Installation Guide (Part No. 5130226), Commissioning Guide (Part No. 5130227) and
Pitched Roof Kit Instructions (Part No. 5130229).
Please leave these instructions with the
User for Safe Keeping
The User Guide Booklet
(Part No. 5130228) shoud be read
in conjunction with these
instructions.
KIT INSTRUCTIONS
Window

2© Baxi Heating UK Ltd 2011
Content
© Baxi Heating UK Ltd 2011.All rights reserved. No part of this publication may be reproduced or
transmitted in any form or by any means, or stored in any retrieval system of any nature (including
in any database), in each case whether electronic, mechanical, recording or otherwise, without prior
written permission of the copyright owner, except for permitted fair dealing under Copyrights,
Designs and Patents Act 1988.
Applications for the copyright owner’s permission to reproduce or make other use of any part of
this publication should be made, giving any details of the proposed use to the following address:
The Company Secretary, Baxi Heating UK Limited, Brooks House, Coventry Road, Warwick. CV34 4LL
Full acknowledgement of author and source must be given.
WARNING: Any person who does any unauthorised act in relation to a copyright work may be
liable to criminal prosecution and civil claims for damages.
1.0 Introduction to Solar 3
2.0 Solar Collector Specifications 4
3.0 Pump Station Specifications 5
4.0 Solar Controller 6
5.0 Ancillary Components 7
6.0 General 8
7.0 Installation of Collector Sensor 10
8.0 Installation of Pump Station 11
9.0 Installation of Solar Controller 13
10.0 Site Requirements 17
11.0 Installation of Solar Collector 19
12.0 Commissioning of System 25
13.0 Commissioning of Hydraulic Station 28
14.0 Commissioning of Solar Controller 29
15.0 Commissioning Record 42
16.0 Maintenance 45
17.0 Fault Finding 46
18.0 Spares 49
19.0 Warranty 51
Section Page
Installation Options
The additional 10 tube pitched roof kit is intended for use
when it is not possible to achieve a correctly sized system via
the standard kits, due to roof obstructions such as a inroof
opening window.
The 10 tube pitched roof kit is only recommended for use with
the 20 tube pitched roof kit part no. 5130214.
This additional kit is not intended for use as a East West kit.

3
© Baxi Heating UK Ltd 2011
1.0 Introduction to Solar
1.1 Description
Thank you for purchasing a high quality Baxi SolarfloTM Solar
Thermal Domestic Hot Water System.
The sun is the ultimate source of most of our renewable
energy supplies. Energy from the sun is clean and abundant.
There is a widely held opinion that the UK does not have
enough sun to make solar systems worthwhile. In fact parts of
the UK have annual solar radiation levels equal to 60% of those
experienced at the equator.
However, this energy is not received uniformly throughout the
year. Some 70% of UK annual radiation is received over the
period April to September and 25% is received in the months
of June and July.
Solar water heating technology captures energy from the sun
and transfers this to a water heater to raise the water
temperature therefore reducing the reliance on fossil fuel
energies such as gas, oil and electricity. Up to 60% of a
dwelling’s annual hot water requirement can be provided by a
solar water heating system.The balance is provided by
traditional means via a second heat exchanger connected to a
fossil fuel boiler or electrical heating by electric boiler or
immersion heater.
The Baxi SolarfloTM water heating system provides all the
principal components required for an efficient solar water
heating system.The sun’s energy is captured by a series of solar
collectors through which a special heat transfer fluid is pumped.
As the fluid passes through the collector its temperature is
raised.The heated fluid is circulated through a heat exchanger
coil in the base of the solar storage cylinder transferring the
heat gained to the stored water, gradually raising its
temperature. The cooled fluid then returns to the collector to
be heated again. Heating by the solar coil is controlled by a
solar differential temperature controller that ensures the system
will only operate when there is useful solar heating gain at the
collector. As the sun’s energy input to the collector is variable
supplementary heating by a conventional boiler or electric
immersion heater should be provided.The optional cylinders
that can be supplied with the Baxi SolarfloTM package provide a
supplementary heat exchanger coil and immersion heater as
standard.
1.2 General
Avoid the use of hacksaws if at all possible. Using the correct
pipe cutting tools will reduce the amount of debris in the
system prior to flushing.
Read in conjunction with Solar Collector Guide.
Fig. 1- Schematic
Cold Feed
Reheat
Sensor
Combi Valve
Drain Points
Flow Meter
Return
Sensor
10 Tube Kit

2.0 Solar collector specifications
4© Baxi Heating UK Ltd 2011
C
AD
B
Table of dimensions (mm)
20 tube 10 tube
A 1418 1209
B 1996 1996
C 1475 737.5
D9797
Fig. 2
2.1 Technical Data
20 tube 10 tube
Gross area: 2.83m21.45m2
Net area: 2.00m21.076m2
Weight: 54.8 kg 27.4 kg
Fluid Volume: 3.8 litres 1.9 litres
Pressure: 8 bar 8 bar
Absorption: 95% 95%
Emission: 5% 5%
Stagnation temp: 286°C 286°C
Glass: 65mmØ Low-iron - transmission 0.92
Light transmittance: >90.8% ± 2%
All dimensions shown in mm
0
2468
10
5
20
15
25
30
35
40
Pressure Drop (mbar)
Flow Rate (l/min)
0
10 tubes
20 tubes
Coefficients of efficiency (20 & 10 tubes)
(determined in the sun simulator SUSI 1)
= o - a1.(tm - ta)/G - a2.(tm - ta)2/G
Based on: aperture area absorber area
o = 0.773 0.830
a1 = 1.43 W/m2K 1.53 W/m2K
a2 = 0.0059 W/m2K 0.0063 W/m2K
Fig. 3

3.0 Pump station specifications
3.1 Technical Data
Dimensions
(Height/Width/Depth) 375/250/190mm
Flow and return connections
(compression fittings) 22mm
Maximum working temperature: 120°C
Maximum working pressure: 6 bar
Pressure Relief Valve setting: 6 bar
Circulating Pump: Grundfos UPS 25-60
/ Wilo ST 25/6
Circulating Pump voltage: 230/240 V ~
Power consumption Setting 1: 40W
Setting 2: 60W
Setting 3: 80W
Maximum Pump Head: 6 metres
Maximum Pump Capacity: 4.5 m3/h / 3.5 m3/h
Flow meter scale: 2 to 15 l/min
Features
Air Separator
Adjustable Control Valves
Drain Point
Temperature Gauges
Flow Gauge
5
© Baxi Heating UK Ltd 2011
Fig. 4

4.0 Solar controller
4.1 Technical Data
Housing Material 100% recyclable ABS
Dimensions
L x W x D in mm 175 x 134 x 56
weight 360 g
Ingress protection IP40 according to VDE 0470
Electrical values
Operating voltage 230/240V ~ 50 Hz
Interference grade N according to VDE 0875
Max. conductor
cross-section
240V-connections 2.5 mm2fine-strand/single-wire
Temperature sensor /
temperature range PTF6 - 25°C to 200°C
PT1000, 1,000 kat 0°C
Test voltage 4 kV 1 min according to
VDE 0631
Switching voltage 230V / 240V
Capability per one
switch output 1A / 230VA for cos j = 0.7-1.0
Total capability of
all outputs 2A / 460VA maximum
Fuse protection fine-wire fuse 5 x 20mm, 2A/T
(2 amperes, slow)
Features
Menu driven operation
System monitoring
Solar gain measurement
Suitable for flat plate and evacuated tube type collectors
Auxiliary heat source control
Can be used in a number of system configurations see Fig. 15
NOTE:This controller is suitable for S plan and Y plan systems.
However, in the event of an installation having a ‘Y’ plan boiler
system that is to be controlled by the solar controller, a relay is
required (not supplied).This is available as a Baxi Spares Item,
Code No. 5122765.
6© Baxi Heating UK Ltd 2011
Fig. 5

7
© Baxi Heating UK Ltd 2011
5.0 Ancillary components
5.1 Expansion Vessel
Membrane expansion tanks for solar primary heating circuit.
Manufactured according to the Directive PED 97/23/CE
(approved noZ-DDK-MUC-02-396876-04).
Factory set charge pressure 2.5 bar.
Butyl membrane suitable for solar primary heating fluid, DIN
4807-3 approval.
Maximum working temperature +110°C.
Maximum percentage of glycol 40% (Pre-mixed).
Connection: 3/4” BSP male parallel
Expansion vessel supplied with wall mounting bracket and self
sealing vessel connection that will allow removal of the vessel for
maintenance without losing solar heat transfer fluid.
Under the following circumstances, a protection vessel should be
used in the Return Leg of the solar loop from the pump station.
The following distances should be observed:
20 tube collectors should have a Protection Vessel fitted if the
expansion vessel is less than 8 metres away from its nearest
collector.This should be sited at a suitable point between the
expansion vessel and nearest collector.
30 tube collectors should have a Protection Vessel fitted if the
expansion vessel is less than 12 metres away from its nearest
collector.This should be sited at a suitable point between the
expansion vessel and nearest collector.
Instances where a protection vessel should be included
20 tube system 30 tube system
Pipe Diameter Distance to nearest collector
15mm <8m <12m
22mm <4m <6m
The size of the protection vessel should be at least the combined
volume of the following:
Total Collector volume + total pipe work volume from collector
to protection vessel.
For positioning on protection vessel (Fig. 7).
5.2 Solar Heat Transfer Fluid
Pre-mixed (40% glycol / 60% water) Solar thermal transfer fluid.
Based on1,2 - propylene glycol with corrosion inhibitors.
DO NOT dilute or mix with water.
Non-toxic, odourless, bio-degradable.
The use of chemical resistant gloves and suitable eye
protection is required when handling.
A full safety data sheet is available on request.
Supplied in 20litre container.Weight of container full - 21kg.
5.3 Thermostatic Blending Valve
Can be set to control the hot water delivered to the user outlets
to a safe working temperature enabling the solar cylinder to store
water at a higher temperature.
Connections: 22mm compression
Max working pressure (static): 14 bar
Max working pressure (dynamic): 5 bar
Min working pressure (dynamic): 0.2 bar
Max inlet pressure ratio: 2:1
Min flow required for stable control: 5 l/min
For pressure drop diagram and dimensions see Figs. 8 & 9
NOTE: For optimum operation the cold connection must be
taken from a balanced cold water feed. For details of balanced
cold water feed please refer to the cylinder manufacturer’s
instructions.
Ø300mm
392mm
3/4”
Expansion vessel
Fig. 6
Flow l/s
Pressure Loss kPa
0.2 0.3 0.4 0.5 0.7 1.0 1.4 2
30
40
50
70
100
120
140
160
180
200
22mm
28mm
60mm
81mm
92mm
22mm
22mm Hot
Mix
Cold
Fig. 9
Fig. 8
Fig. 7

6.0 General
6.1 Safety Information
In order to reduce the number of fatalities and major accidents
attributable to work at height, the Health and Safety Executive
has introduced comprehensive regulations and guidance that
should be followed by all businesses working at height.
We consider in the following paragraphs some of the main
features of the regulations and guidance.This is, however, only a
limited summary and it is recommended that all businesses
planning on undertaking solar water heating installations obtain
a copy of the regulations and guidance issued by the Health
and Safety Executive and carefully consider the contents.
The regulations and guidance state that you are required to
carry out a risk assessment for all work conducted at
height and to put in place arrangements for:
• Eliminating or minimising risks from work at height.
• Safe systems of work for organising and performing work
at height.
• Safe systems for selecting suitable work equipment.
• Safe systems for protecting people from the consequences
of work at height.
The regulations and guidance highlight a hierarchy for safe
work at height:
•Avoid the risk by not working at height if practicable.
•Prevent falls, where it is not reasonably practicable to
avoid work at height; you are required to take suitable and
sufficient steps to prevent the risk of a fall including
selecting the most suitable work equipment
(in accordance with the regulations).
•Mitigate the consequences of a fall; where the risk of a
person or object falling still remains, take suitable and
sufficient measures to minimise the distance and
consequences of any fall.
Collective protection measures, such as guard rails on scaffold,
should be given priority over personal protection measures,
such as safety harnesses.
Within the regulations’ framework, you are required to:
1) Assess the risk to help you decide how to work safely.
2) Follow the hierarchy for safe work at height (i.e. avoid,
prevent and mitigate).
3) Plan and organise your work properly, taking account of
weather conditions and the possibility of emergencies.
4) Make sure those working at height are competent.
5) Make use of appropriate work equipment.
6) Manage the risks from working on or around fragile surfaces
and from falling objects.
7) Inspect and maintain the work equipment to be used and
inspect the place where the work will be carried out
(including access and egress).
When preparing to install a solar water heating system, it is
required that you perform a risk assessment in relation
to work at height and plan how you will organise your work,
taking into account the site, the weather conditions
and the experience and competence of colleagues or
contractors who may be working at height with you.
8© Baxi Heating UK Ltd 2011

6.0 General
9
© Baxi Heating UK Ltd 2011
6.2 Risk Assessments
The HSE has published a number of very useful free
publications that advise how to undertake risk assessments.
Two of these that you should obtain are:
Five Steps to Risk Assessment.
A Guide to Risk Assessment Requirements.
The five steps outlined in the HSE leaflet are:
Step 1: Look for the hazards
This will mean looking at the site and identifying significant
hazards.These could be features such as a steep roof, a fragile
surface where the collectors may be mounted, uneven ground
or obstructions where access to the roof might be required.
Step 2: Decide who may be harmed and how
This might mean considering the particular risks that young
workers or trainees might face and thinking about the
residents of the household or visitors who could be hurt by
your activities.
Step 3: Evaluate the risks and decide which precautions should
be made You should consider how likely it is that each hazard
will cause harm, decide which precautions you might take and
then assess, after you have taken those precautions, whether
the remaining risk will be high, medium or low. Where you
identify remaining risks, you should consider which further
action you could take to control the risks so that harm is
unlikely.
Step 4: Record your findings
If you have fewer than five employees you do not need to
write anything down, though it is useful to keep a written
record of what you have done. If you employ five or more
people you must record the significant findings of your
assessment.You must also tell your employees about your
findings.You need to be able to show that a proper check was
made, that you considered who might be affected, that you
dealt with all the obvious significant hazards, that the
precautions you propose are reasonable and that the
remaining risk is low.
Step 5: Review your assessment if necessary
Each solar water heating installation may bring its own
challenges and present its own particular hazards.You should
therefore be careful not to rely on a “standard” risk assessment
for installing a solar water heating system in a house, but
review the particular hazards for each new situation.The issue
of work equipment must be considered, but at the preparation
stage you should consider where scaffold or other access
equipment might be positioned and look out for any obvious
obstacles to this, such as a conservatory or porch.
In addition to the risks associated with work at height, you
should also consider the risks associated with lifting and
carrying solar collectors, using electric drills and using blow
lamps or blow torches for soldering.This is not an exclusive list
and so you should consider all aspects of the proposed
installation to assess whether there are additional risks that
need to be taken into account.

10 © Baxi Heating UK Ltd 2011
7.1 Installation
For the 10 tube addition, only one solar sensor is required.The
solar sensor should be placed in the last sensor pocket in
series. If one of the tube arrays is position such that more solar
gain would be achieved then the sensor should be located in
that manifold sensing pocket.
The Solar Collector temperature sensor should be installed in
the sensor pocket securely.The sensor with the black silicone
sheathing must be used in the solar collector pocket.
All materials used for installing temperature sensors (sensor
element, conducting compound, cables, sealing and insulating
materials) must be suitably temperature resistant (up to
200°C).
Solar Collector sensor may be extended (using the 13m
extension cable supplied).
The sensor may be extended up to 50m but 0.75mm
screened flex must be used.
7.0 Installation of collector sensor
Fig. 10

11
© Baxi Heating UK Ltd 2011
8.0 Installation of pump station
8.1 Identification of Components (Fig. 11)
The main components of the pump station are:
– Two isolating valves (Fig. 11, Item 1 & 2) with integral
thermometers which display the solar primary flow
and return temperatures.
– A safety group (Fig. 11, Item 3, supplied unconnected),
which protects the solar primary circuit.The pressure
relief valve and pressure gauge are integrated in the
safety group.
– A non-return valve in both feed and return prevents
the possibility of gravity circulation in the solar
primary circuit.
– A solar circulation pump (Fig. 11, Item 4).
– A flow gauge and regulator with fill & drain valve and
shut-off valve (Fig. 11, Item 5).
– An air separator.
The heat transfer fluid is circulated by the solar circulation
pump integrated in the hydraulic pump station (Fig. 11).
In most instances the 20 litre container of Tyfocor LS will be
sufficient quantity of transfer fluid to fill 30 metres of pipework
when connected to a capacity of 30 tubes.
The pump station has a solar controller (Fig. 11 Item 6)
integrated into the front insulation moulding.This is pre-wired
to the solar pump.
Fig. 11
21 3
4
5
6

12 © Baxi Heating UK Ltd 2011
8.0 Installation of pump station
8.2 Pipework installation - general
Connections supplied are suitable for pipe diameters up to
22mm. However for short pipe runs (up to 10m flow and
return) the use of 15mm diameter pipe is acceptable.
The height difference between the highest point in the
pipework (collector) and the pump station may be a maximum
of 15m (this is called the ‘static height’). If the static height is
greater than 15m a larger expansion vessel may be required.
Earthing pipework
All solar primary pipework between the solar collectors,
hydraulic station and solar cylinder must be earth bonded to
avoid electrical potential differences.This work must be carried
out by a qualified electrician.
Fit earthing clamps to the solar primary flow and return pipes
and connect the earth clamps to the earthing system of the
property using an earth bonding cable of min. 6mm2diameter.
Venting the pipework
The Baxi SolarfloTM hydraulic station includes an air
collector/separator and bleed point so an automatic air vent is
not necessary. Any section of solar pipework that falls and rises
again may require an additional air vent valve to relieve any
trapped air which may cause air locking in the system.The air
vent must be compatible with solar primary systems, i.e. be
resistant to glycol and temperatures up to 200ºC.
Insulating the pipework
External pipework should be insulated with high temperature
resistant materials and be protected against UV degradation.
Internal pipework, especially through unheated spaces such as a
loft space, should also be insulated with high temperature
resistant materials. The Baxi SolarfloTM is supplied with 2x2m
pre insulated flexible stainless steel tubes and with additional
lengths (30m) of stainless steel flexible tubes and high
temperature insulation.
8.3 Solar Expansion Vessel
Solar expansion vessel has a pre-set pressure of 2.5 bar and
must be adjusted to suit your installation.
The charge pressure at the solar expansion vessel should be
adjusted such that when not under load the charge pressure is
0.7 bar above the static system head (the height of the top of
the collector panels above the hydraulic station). A one metre
head represents 0.1 bar. However, the charge pressure should
be at least 1.5 bar.
The maximum static system head is 15m (1.5 bar).
Fig. 12

13
© Baxi Heating UK Ltd 2011
9.0 Installation of solar controller
PE
L
N
N
A1
N
A2
N
A3
WMM
T1
T2
T3
T4
T5
T6
mains 230/240 V area low voltage area (SELV)
PE Earthed connection
L Mains supply live conductor
N Mains supply neutral conductor
A1 Switch output to solar pump
N Neutral wire to solar pump
A2 Switch output 2 to second
system pump if used (east/west)
N Neutral wire switch output 2
A3 Switch output 3 to auxiliary
heating control
N Neutral wire switch output 3
For switch functions A2 and A3
see Fig. 15
Fig. 13
230V/240V~
Mains supply
L
N
E
Solar
differential
controller
Hydraulic Station
Fused Double pole
isolating switch
Solar coil
over-temp
cut-out
Fig. 14
9.1 General connection guidelines.
In the case of all connecting wires the outer sheath should be
stripped back to 80mm.The individual conductor sleeving
should be stripped approx. 10mm.
Flexible cables are inserted in the controller through
knockouts provided in the controller backplate.
Flexible cables must be secured against straining by suitable
strain relief bushes or devices.
Protect flexible cables from damage by hot pipework.
The controller must be earthed.
9.2 230/240V~ connections
For 230V connections you must follow the following points:
The mains supply to the controller should be via a suitable
fused double pole isolating switch with a contact separation of
at least 3mm in both poles. Additionally for unvented solar
cylinders the controller should be wired via the solar coil over
temperature cutout such that power is interrupted to the
controller and hydraulic station in the event of the unvented
cylinder overheating (see Fig. 14).
Controllers are intended for the operation in 230/240V~
/50Hz mains. Any motorised valves connected must be
suitable for this voltage.
All earth wires must be connected to terminals marked with
PE. Any bare wire earth conductors must be sleeved with
green/yellow sleeving.
The neutral terminals (N) are electrically connected and are
not switched.
All switch outputs (A1, A2 and A3) are 230/240V~ 1 Amp
max load outputs. If voltage free contacts are required, this
must be done via a relay (see Figs. 16 or 17 Block Wiring
Scheme C or E) order accessory Code No. 5122765.
NOTE:The Solar Differential Controller’s internal 1A switch
outputs are not suitable for Y plan systems.
NOTE:This controller is suitable for S plan and Y plan
systems. However, in the event of an installation having a ‘Y’
plan boiler system that is to be controlled by the solar
controller, a relay is required (not supplied).This is available as
a Baxi Spares Item, Code No. 5122765.
WMM Flow meter
T1 Temp.- sensor collector 1
T2 Temp.- storage tank 1
T3 Temp.- sensor collector
2/storage tank 2
T4 Temp.- sensor collector
return
T5 Temp.- sensor thermostat
or for 2nd temperature
differential controller
T6 Temp.- frost protection or
for 2nd temperature
differential controller
Fuse Rating:T 2A L 250V

9.0 Installation of solar controller
14 © Baxi Heating UK Ltd 2011
Collector
Type 0:
1 collector, 1 storage tank
Tcoll
Tr e t
FM
P
Storage tank
Tth
Tst
Collector
Type 2:
1 collector, 2 storage tanks
with 2 pumps
Tcoll
Tr e t
FM
P1
Storage tank1 Storage tank2
Tth
Tst1 Tst2
P2
Collector 1
Type 4:
2 collectors, 1 storage tank
with 2 pumps
Tcoll1 Tcoll2
P1 P2
Tr e t
FM
Storage tank1
Tth
Tst
System type Sensor terminal designation (see Fig. 13)
Type Description T1 T2 T3 T4 T5 T6
0 1 collector array, 1 storage cylinder Tcoll1 Tst1 - Tret Tth
2 1 collector array, 2 storage cylinder (pump-pump) Tcoll1 Tst1 Tst2 Tret Tth
4 2 collector array, 1 storage cylinder (pump-pump) Tcoll1 Tst1 Tcoll2 Tret Tth
NOTE:The solar gain flowmeter must be connected to sensor terminals marked WMM (see Fig. 13).
System type Output terminal designation (see Fig. 13)
Type Description A1 A2 A3
0 1 collector array, 1 storage cylinder P1 - Auxiliary heating
2 1 collector array, 2 storage cylinder (pump-pump) P1 P2
4 2 collector array, 1 storage cylinder (pump-pump) P1 P2
Fig. 15
9.3 Solar Gain measurement
For solar gain measurement it is necessary to fit the
flowmeter and collector return sensor (Tret) as shown in the
diagram in Fig. 15.The collector return sensor must be
securely attached to the return pipework using the securing
ties supplied and then covered by insulation.The solar gain of
the system is calculated on the basis of the temperature
difference between the collector flow and return and the
solar primary circulation flow rate.
The function must be switched “on” when commissioning
the Solar Controller. Refer to the Baxi SolarfloTM
“Commissioning, Maintenance & Servicing Guide” for further
details.
For System Types 2 and 4 the additional pump (P2) can be
ordered as an accessory, Part No. 5129362
Tcoll Temperature measuring point collector
Tth Temperature measuring point thermostat auxiliary
sensor
Tret Temperature measuring point collector return
Tst Temperature measuring point storage tank
PPump
FM Flowmeter

15
© Baxi Heating UK Ltd 2011
9.0 Installation of solar controller
9.4 Connection of temperature sensors
The sensor with black silicone sheathing must be used for
the solar collector sensor.
The controller uses precise platinum temperature sensors type
PT1000.The controller is supplied with 3 sensors.
Installation / cabling of temperature sensors:
Mount the sensors in the pockets provided in the collector
and storage tank.
The wires of the temperature sensors can be lengthened. Up
to 15m long you need a 2 x 0,5mm2cross-section, up to 50m
2 x 0,75mm2. In the case of long connections (collector)
shielded extension lead must be used.
DO NOT run sensor leads adjacent to mains carrying voltage
conductors (at least 50mm separation is recommended).
Temperature sensors are connected according to the
appropriate terminals, refer to Fig 13.
The sensors are polarity free.
Sensors MUST NOT be connected to the 230/240V~
terminals.
9.5 Control of Auxiliary heat input
When using the reheat function the operation of the auxiliary
heat input device can be controlled via output A3 from the
controller.
The reheat sensor cable should be connected to terminal T5
of the solar controller and the sensor element inserted into
the controls pocket at the auxiliary heater level.
NOTE: The maximum switching current of the controller
is 2 Amp in total, 1 Amp per output. If switching an electrical
immersion heater or using a 3 port valve system this MUST
be done via a relay (see Figs. 16 or 17 Block Wiring Scheme C
or E) order accessory code No. 5122765.
If using a boiler for auxiliary input, the output from the reheat
function should be integrated into the boiler control circuit.
3A Fused Supply
L
1
1
710 3
123E
2345678910TerminalBox(Notsupplied)
23 235 12376
NE LNESL LNE
DHW ON CH ON
Boiler Terminal Strip Programmer
1
Solar Cylinder Auxiliary Controls
692
12N
Room Stat
18
Solar
Controller
Boiler Immersion
3
12E
Solar O/Temp Cutout
382
PE L N
Solar Differential Controller
11
A1
12
NT1T2T4WMM
423
LNE
CH Pump
A1 N PE
11 12 E
Solar Pump
32101
G/Y BL BR GR
DHW 2 Port Valve
5
OR
329 1
G/Y BL BR GR
CH 2 Port Valve
5
OR
See Fig. 13
3A Fused Supply
L
1
1
710 3
123E
2345678910TerminalBox(Notsupplied)
23 235 1219
NE NESL LN1 2
Boiler Terminal Strip Programmable Room Stat
1
L
4
PL
Solar Cylinder Auxiliary Controls
13
12E
Solar O/Temp Cutout
8
382
PE L N
Solar Differential Controller
11
A1
12 7 2
N A3 N T1 T2 T4 T5 WMM
423
LNE
CH Pump
A1 N PE
11 12 E
Solar Pump
32101
G/Y BL BR GR
DHW 2 Port Valve
5
OR
329 1
G/Y BL BR GR
CH 2 Port Valve
5
OR
See Fig. 13
3 Amp Fused Supply
L
1
12345678910TerminalBox(Notsupplied)
23
NE
13 Amp Fused Supply
L
456
NE
183
12E
Solar O/Temp Cutout
756
LNE
Immersion Heater
A3 N 4
1 5 CoM
Auxiliary Immersion Heater Relay
7
No
382
PE L N
Solar Differential Controller
11
A1
12
N A3 N T1 T2 T4 T5 WMM
A1 N PE
11 12 E
Solar Pump
See Fig.13Relay
PL
4
Fig. 16
Block Wiring Schemes
A. Baxi SolarfloTM in conjunction with auxiliary heating by boiler - no reheat
control by solar controller.
B. Solarflo in conjunction with auxiliary heating by boiler - reheat control
via solar controller.
Note: If boiler has PL - Pump Live connection, pump must be connected to
this (4), if not Pump Live should be connected to SL (5).
C. Solar Cylinder with auxiliary heating by immersion heater.
NOTE:Arrows identify wires which go to wiring centre terminal block.

16 © Baxi Heating UK Ltd 2011
9.0 Installation of solar controller
3A Fused Supply
L
1
1
85 3
123E
2345678910TerminalBox(Notsupplied)
23 123 12387
NE LNESL LNE
DHW ON DHW OFF
Boiler Terminal Strip Programmer
5
Solar Cylinder Auxiliary Controls
7
492
12N
Room Stat
16
Solar
Controller
3
12E
Solar O/Temp Cutout
362
PE L N
Solar Differential Controller
11
A1
12
NT1T2T4WMM
423
LNE
CH Pump
A1 N PE
11 12 E
Solar Pump
3 2 5 NOT USED
G/Y BL BR GR
Cylinder Safety Valve
OR
329 7
G/Y BL WH GR
3 Port Mid PositionValve
5
OR
4
CH ON
See Fig. 13
3A Fused Supply
L
1
1
85 3
123E
2345678910TerminalBox(Notsupplied)
23 123 1219
NE LNESL LN1 2
Boiler Terminal Strip Programmable Room Stat
5
Solar Cylinder Auxiliary Controls
7
163
12E
Solar O/Temp Cutout
362
PE L N
Solar Differential Controller
11
A1
12
N A3 N T1 T2 T4 T5 WMM
523
LNE
CH Pump
A1 N PE
11 12 E
Solar Pump
3 2 5 NOT USED
G/Y BL BR GR
Cylinder Safety Valve
OR
329 7
G/Y BL WH GR
3 Port Mid PositionValve
5
OR
See Fig. 13
4
PL
4
L
Relay
A3 N 1
1 5 CoM
Relay
8
No
E. Auxiliary heating by boiler with 3 port mid position valve system
- reheat control by solar controller.
Key to abbreviations:
L-Live
N - Neutral
E-Earth
PL - Pump Live
SL - Switched Live
G/Y - Green and Yellow
BL - Blue
BR - Brown
GR - Grey
OR - Orange
WH - White
The wiring schemes assume the use of an unvented Solar
DHW cylinder.
NOTE: For open vented cylinders 1 to 6 connection is
required in the wiring centre.
These diagrams are presented for guidance only, terminal
numbers may differ between different manufacturers
equipment.
The various ancillary equipment manufacturers should be
consulted to confirm the correct operation of their products
within the system.
The Warranty only applies to equipment and controls supplied
with the Solarflo System.
D. Auxiliary heating by boiler with 3 port mid position valve system
- no reheat control by solar controller.
NOTE: Must use 2 port safety valve supplied with cylinder
NOTE: Must use 2 port safety valve supplied with cylinder
Fig. 17

17
© Baxi Heating UK Ltd 2011
10.0 Site Requirements
Noggin Rafter
Fig. 18
10.1 General assembly notes
These instructions relate to the installation of the Baxi SolarfloTM
Evacuated Tube Collector Pitched Roof Mounting. Parts are
provided for fixing to slate or tile roofs. Refer to the parts list
to ensure the correct components are in the pack. All other
equipment must be installed as detailed in the Baxi SolarfloTM
Installation Guide.
Use only Baxi SolarfloTM mounting systems. Use of other
brackets/mounting systems will invalidate the warranty and may
result in an insecure and dangerous evacuated tube collector
installation.
The mounting brackets must be fixed to the roof structural
members.They must never be fixed to roofing laths. If suitably
positioned structural members are not available or, if they are
of a section that may be weakened by the inserting of the fixing
screws, additional noggins should be inserted between the
structural members.These must be at least the same cross
section as the structural member.
Use only the corrosion resistant fastenings supplied. Holes
through any roof waterproofing materials should be sealed with
an appropriate UV and weather resistant sealant.
10.2 Structure
The collectors may only be mounted on sufficiently
load-bearing roof surfaces and substructures. It is essential that
the structural load-bearing capacity of the roof and the
substructure must be assessed before mounting the collectors.
Particular attention should be paid to the quality of the
(timber) substructure in terms of the stability of the screw
joints necessary for installing the collector mounting brackets.
Where roof structure is not strong enough noggins must be
inserted to accept anchor screws.The roof structure must be
able to take the wind and snow loads that can occur. The
assessment should also take into account any special features of
the particular site that could lead to increased loads (air jets or
eddy formations, etc).
10.3 Lightning protection / Equipotential bonding of
the building
It is not necessary to connect collector arrays to the lightning
protection of the building. For installations on metal
substructures at the installation site, authorised lightning
protection specialists must be consulted.The metal pipes of the
solar circuit must be earth bonded to the main earthing circuit
by means of a conductor (green/yellow) with a cross-section of
at least 6mm2.

10.0 Site Requirements
18 © Baxi Heating UK Ltd 2011
10.4 Connections
Ensure the sealing washer provided is inserted between the
male and female connections. All connecting pipe work and
fittings must be of a suitable metal; either copper, brass or
stainless steel. Soft soldered joints must not be used. Any seals
or sealing compounds must be resistant to temperatures of up
to 200°C and be resistant up to a 50% glycol/water mix.
When tightening the connections, always apply counter-
pressure with a wrench or another spanner to prevent
damage.
10.5 Collector inclination for Pitched Roof Mounting
The collector is suitable for angles between 0 - 90°.
The roof aspect should ideally face South, however
orientations between 30° East and 40°West of South are
acceptable. Fig. 19 shows the efficiency loss for varying angles
of inclinations and roof orientation (Portrait & Landscape).
10.6 Solar fluid
The Baxi SolarfloTM collector tubes MUST be protected with
the supplied fluid. Top-ups cannot be made with water, only
use the fluid supplied (Tyfocor LS). Systems found to have
lower glycol concentrations will not be covered by the
warranty.
10.7 Collector location
Under no circumstances should the collector be fitted where it
overhangs any part of the roof structure.
Minimum clearances must also be adhered to for servicing and
or replacement of parts (see Fig. 20).
10°10°
20°20°
30°30°
40°40°
50°50°
60°60°
70°70°
80°80°
90°
Angle of tilt
North
South
less than optimum by 0-5% 5-10% 10-20%
East
S.E.S.W.
West
90°
Fig. 19
120mm
200mm
170mm 170mm
200mm
Fig. 20

11.0 Installation of solar collector
19
© Baxi Heating UK Ltd 2011
11.1 Collector Orientation
The pitched roof mounted collector may be orientated
portrait or landscape to suit installation. Assess the location for
installation and determine which orientation is required.
11.2 Assembly of Kit
Prior to installation check that the following packs are available
Manufacturer’s
Part No
Manifold Pack 20 tubes 5130220
10 tubes
Sloping Roof Fixing Pack 5130223
Tube Box (10 off) 5130222
(ensure enough boxes for installation)
Connection Kit 5130224
Installation (Portrait)
Installation (Landscape)
1400 - 1700mm
600 - 1100mm (20 tubes)
800 - 1400mm (30 tubes) Form by hand to suit
Tile Shape
900 - 1100mm (20 tubes)
1200 - 1400mmb (30 tubes)
700 - 1400mm
Form by hand to suit
Tile Shape
Fig. 21
Fig. 22

11.0 Installation of solar collector
20 © Baxi Heating UK Ltd 2011
11.3 Bracket Fixing
Prior to fixing the mounting brackets to the roof structure,
adjust the assembly for your selected installation, portrait or
landscape.
1. Remove the rubber cover.
2. Untighten the two nuts which secure the angle bracket
(Fig. 23).
3. Adjust the angle bracket to the correct orientation (portrait
or landscape) for the installation (Figs. 23 & 24).
4. Resecure with the bolts and nuts.
5. Refit the rubber cover.
Form mounting bracket by
hand to suit Tile Shape
Portrait Roof Installation
Landscape Roof Installation
Example on how the
side rails will fix to the
mounting brackets
(portrait)
Example on how the
side rails will fix to the
mounting brackets
(Landscape)
Fig. 23
Fig. 24
Angle Bracket
Rubber Cover
Form mounting bracket by
hand to suit Tile Shape
Angle Bracket
Rubber Cover
Side Rail