Santon Premier Plus 120 User guide

PRE-PLUMBED UNVENTED MAINS PRESSURE WATER HEATER
120, 150, 170, 210, 250 and 300 LITRE CAPACITY INDIRECT MODELS
INSTALLATION AND SERVICING INSTRUCTIONS
IMPORTANT: PLEASE READ AND UNDERSTAND THESE INSTRUCTIONS
BEFORE COMMENCING INSTALLATION. PLEASE LEAVE THIS MANUAL
WITH THE CUSTOMER FOR FUTURE REFERENCE.

CONTENTS
INTRODUCTION.................................................................................................................................3
GENERAL REQUIREMENTS...................................................................................................................4
INSTALLATION – GENERAL..................................................................................................................9
INSTALLATION - DISCHARGE .............................................................................................................12
INSTALLATION - PRIMARY CIRCUIT ....................................................................................................15
COMMISSIONING .............................................................................................................................18
MAINTENANCE..................................................................................................................................19
USER INSTRUCTIONS.........................................................................................................................20
FAULT FINDING & SERVICING............................................................................................................22
SPARE PARTS......................................................................................................................................23
GUARANTEE ......................................................................................................................................25
ENVIROMENTAL INFORMATION.........................................................................................................25
COMMISSIONING CHECK LIST ..........................................................................................................26
SERVICE RECORD...............................................................................................................................27
TECHNICAL SUPPORT........................................................................................................................28
THE BENCHMARK SCHEME
Benchmark places responsibilities on both manufacturers and installers. The purpose is to ensure that customers are
provided with the correct equipment for their needs, that it is installed, commissioned and serviced in accordance with the
manufacturer’s instructions by competent persons and that it meets the requirements of the appropriate Building Regulations.
The Benchmark Checklist can be used to demonstrate compliance with Building Regulations and should be provided to the
customer for future reference.
Installers are required to carry out installation, commissioning and servicing work in accordance with the Benchmark Code
of Practice which is available from the Heating and Hotwater Industry Council who manage and promote the scheme. Visit
www.centralheating.co.uk for more information.
IMPORTANT NOTE TO USER: PLEASE REFER TO THE USER INSTRUCTIONS SECTION ON PAGE 20 FOR IMPORTANT
INFORMATION WITH RESPECT TO THE BENCHMARK SCHEME
2

INTRODUCTION
The PremierPlus SystemFit is a factory pre-plumbed and wired PremierPlus unvented water heater. The PremierPlus SystemFit
is manufactured in the UK from top quality materials and meets all the latest relevant safety and constructional standards.
The high grade Duplex stainless steel cylinder offers exceptional strength and corrosion resistance which is backed by a 30
year guarantee (see terms and conditions on page 25). Its performance, control system and insulation levels exceed the
latest requirements of Building Regulation Part L.
The PremierPlus SystemFit unvented water heater can be fed directly from the cold water mains supply to the property
without the need for separate feed cisterns or vent pipes. It is supplied tted with all its necessary inlet and safety controls for
compliance with Building Regulations. Also tted are a primary circulating pump, automatic bypass valve, a ow balancing
valve, 2 x 2 port motorised valves, primary lling loop and pressure gauge, a cylinder thermostat, thermal cut-out and
wiring centre. The pump, motorised valves and thermal controls are supplied pre-wired. A heating and domestic hot water
programmer, room temperature sensor, primary expansion vessel, automatic air vent and primary expansion relief valve
are supplied loose for installation at a convenient position within the property. An electric immersion heater is also tted to
enable the unit to be heated should the boiler be turned off.
The PremierPlus SystemFit primary circuit can be connected to a variety of gas or oil red boiler types, either open vented
or sealed system. It is not recommended for use with “system” boilers as these already incorporate their own circulating
pump and controls.
NOTE: If using a sealed heating system, adequate provision for expansion within the primary circuit MUST be provided
by tting the primary circuit expansion vessel supplied. Primary circuit expansion cannot be accommodated within the
PremierPlus SystemFit. Ensure the primary circuit expansion relief valve (supplied) is tted to the primary circuit.
The safety valves tted to the PremierPlus SystemFit protect the water heater only. Failure to provide adequate primary
system pressure relief when using a sealed heating system will invalidate the boiler manufacturer’s warranty. Consult the
boiler manufacturer’s installation instructions for further advice.
3

GENERAL REQUIREMENTS
IMPORTANT: THIS APPLIANCE CAN BE USED BY CHILDREN AGED FROM 8 YEARS AND ABOVE AND PERSONS WITH
REDUCED PHYSICAL SENSORY OR MENTAL CAPABILITIES OR LACK OF EXPERIENCE AND KNOWLEDGE IF THEY HAVE
BEEN GIVEN SUPERVISORY OR INSTRUCTION CONCERNING USE OF THE APPLIANCE IN A SAFE WAY AND UNDERSTAND
THE HAZARDS INVOLVED. CHILDREN SHALL NOT PLAY WITH THE APPLIANCE. CLEANING AND USER MAINTENANCE
SHALL NOT BE MADE BY CHILDREN WITHOUT SUPERVISION.
WARNING: Do not switch on if there is a possibility that the water in the heater is frozen.
COMPONENT CHECK LIST
Before commencing installation check that all the components for your PremierPlus SystemFit unit are contained in the
package. The following components are supplied with your PremierPlus Systemt unit:
• Factory tted immersion heater(s) and thermal controls
• Cold water combination valve (comprises pressure reducing valve, strainer, check valve) (supplied loose)
• Factory tted expansion core unit (comprises expansion valve and check valve)
• Potable water expansion vessel (supplied loose) factory tted temperature/pressure relief valve (set at 90°C/10 bar)
• Tundish
• Factory tted indirect thermostat and thermal cut-out
• 2 x 2-port motorised valve
• Primary circulating pump
• Lock-shield ow balancing valve
• Automatic bypass valve
• Primary circuit lling loop
• Primary circuit pressure gauge
• Automatic air vent
• Primary circuit expansion vessel (supplied loose)
• CH/DHW programmer and room temperature sensor (supplied loose)
SITING THE UNIT
The PremierPlus SystemFit unit must be vertically oor mounted. It can be placed anywhere convenient provided the discharge
pipe(s) from its safety valves can be correctly installed. Areas that are subject to freezing must be avoided. Ensure that the
oor is of sufcient strength to support the “full” weight of the unit (table 1, page 5). Pipe runs should be kept as short as
possible for maximum economy. Access to associated controls, immersion heaters and indirect controls should be possible
for servicing and maintenance of the system.
To aid installation the PremierPlus SystemFit is provided with lifting points located in the base and top mouldings. A oor
template is also provided to aid positioning.
If you choose to install the PremierPlus SystemFit in the highest point in the property (e.g. loft space), it is advisable to install
an additional automatic air vent (AAV) (not supplied - available as spare, part number 95 605 050) above the pump to enable
air to be removed from the system. The addition of the AAV is not required if siting the cylinder in a lower position.
WATER SUPPLY
Bear in mind that the water supply to the property will be supplying both the hot and cold water requirements simultaneously.
It is recommended that the maximum water demand is assessed and the water supply checked to ensure this demand can
be satisfactorily met.
NOTE: A high water pressure will not always guarantee high ow rates.
Wherever possible the PremierPlus Systemt supply pipe should be 22mm. We suggest the minimum supply requirements
should be 1.5 bar pressure and 20 litres per minute ow rate. However, at these values outlet ow rates may be poor if several
outlets are used simultaneously. The higher the available pressure and ow rate the better the system performance.
The PremierPlus SystemFit cylinder has an operating pressure of 3.5 bar which is controlled by the cold water combination
valve assembly. The cold water combination valve assembly can be connected to a maximum pressure of 16 bar.
4

OUTLET/TERMINAL FITTINGS (TAPS, ETC.)
The PremierPlus SystemFit can be used in conjunction with most types of terminal ttings, plumbing ttings and pipework.
However, the rated pressures of any ttings selected should be checked for compatibility before installation.
NOTE: Accessories, plumbing ttings and pipework should have a rated operating pressure of at least 6 bar.
Outlets situated higher than the PremierPlus SystemFit unit will give outlet pressures lower than that at the heater, a
10m height difference will result in a 1 bar pressure reduction at the outlet tting.
LIMITATIONS
The PremierPlus SystemFit cylinder should not be used in association with any of the following:
• Solid fuel boilers or any other boiler in which the energy input is not under effective thermostatic control, unless additional
and appropriate safety measures are installed.
• Ascending spray type bidets or any other class 1 back syphonage risk require that a type A air gap be employed.
• Steam heating plants unless additional and appropriate safety devices are installed.
• Situations where maintenance is likely to be neglected or safety devices tampered with.
• Water supplies that have either inadequate pressure or where the supply may be intermittent.
• Situations where it is not possible to safely pipe away any discharge from the safety valves.
• In areas where the water consistently contains a high proportion of solids, e.g. suspended matter that could block the
strainer unless adequate ltration can be ensured.
OPERATIONAL SUMMARY
Maximum PremierPlus pressure 16 bar
Operating pressure 3.5 bar
Expansion vessel pressure 3.5 bar
Expansion relief valve setting 6 bar
T&P relief valve setting 90°C/10 bar
Maximum primary circuit pressure 3 bar
Pressure drop (primary coil) 0.02MPa (0.02 bar)
Storage capacity See Table 1 below
Weight when full See Table 1 below
OUTLINE SPECIFICATIONS
Outer casing: White textured plastic coated corrosion resistant steel
Water container: Duplex stainless steel. 100% pressure tested to 1.5 MPa (15 bar).
Thermal insulation: CFC/HCFC free re retardant expanded polyurethane foam with zero ozone depletion potential. It has
a Global Warming Potential (GWP) of 3.1. Nominal thickness 50mm.
Pipe connections: All connections accept 22mm outside diameter pipe – compression nuts and olives supplied. Thread rate
is 3/4” BSP male parallel to accept standard 3/4” BSP female ttings if required.
Table 1 - Unit Weights & Standing Heat Loss
Nominal Capacity
(litres)
Weight of full unit
(kg) Weight of unit (kg) Standing Heat Loss
per day (kWh/24h) per year kWh/365d)
120 159 39 1.25 456.3
150 196 43 1.45 529.3
170 215 45 1.63 595.0
210 263 53 1.91 697.2
250 312 62 2.22 810.3
300 372 72 2.52 919.8
5

Fig 1 - General Dimensions
Table 2 - Dimensions and Performance
6
NOMINAL
CAPACITY
(litres)
DIMENSIONS (mm) COIL HEATING
TIME IMM
HEATER
(mins)
A B C D RATING
(kW)
HEAT
UP TIME
(mins)
HOT WATER
DRAW-OFF
(litres) TO
40°C
120 936* 382 728 650 15.4 24 108 121
150 1119 563 917 650 15.9 29 135 152
170 1245 691 1039 650 17. 3 30 157 173
210 1503 952 1300 650 19.2 34 199 215
250 1755 1139 1460 650 18.6 42 240 257
300 2069 1460 1805 650 18.8 49 273 310
Notes:
1. Heat up time from cold through 45°C, with a primary ow rate 15ltrs/min at 80°C +/- 2°C.
2. Direct heating times assume use of lower element only, from cold, through 45°C.
3. Cylinders tested to BS EN 12897:2006
* Top of pump extends 95mm above this height
340 284
284412
A
B
C
D
256
Dashed line denotes minimum space
requirement
Pipework layout will vary by model

Danfoss TP9000 Programmable thermostat with timed Domestic
Hot Water (DHW) control:
Programmer dimensions: 135mm (W) x 88mm (H) x 32mm (D)
Room temperature sensor dimensions: 60mm (W) x 45mm (H) x 21mm (D)
Power supply: 220V/240V ac, 50Hz
Switch action 2 x SPDT, Type 1B. Switch rating 220/240V ac, 50/60Hz, 3(1)A
Power reserve: Minimum 24 hours
Memory back up retained for life of product
Enclosure rating: IP30
Control temperature range: Selectable 5 to 30°C
Holiday mode with room temperature setback
Timing accuracy: +/- 1 minute/month
Maximum ambient temperature: 45°C
Honeywell 2 Port motorised valves:
Model No.: V4043H
Voltage rating: 230V ac, 50HZ
Power consumption: 6W
Primary water temperature range: 5 to 88°C
Maximum ambient temperature: 52°C
Automatic differential by-pass valve:
Model No.: RWC DIFF 200 005
Setting range: 0 to 0.05 MPa (0 to 0.5 bar) differential pressure
Maximum primary water temperature: 110°C
Maximum operating pressure 1.0MPa (10 bar)
Graph 1 - Bypass valve pressure vs volume
7

Primary circulating pump:
Model No: Grundfos
Working pressure: 1 MPa (10 bar) max.
Voltage rating: 230V ac, 50Hz
Starting capacitor: 2µF
Enclosure rating: IP42
Electrical data
SPEED
SETTING
SPEED
R.P.M.
INPUT
POWER (W)
FULL LOAD
CURRENT (A)
LOCKED ROTOR
CURRENT (A)
lll 1750 95 0.44 0.47
ll 1100 65 0.30 0.31
l 750 40 0.17 0.18
1
3
2
0.0
0.0
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2
0.5 2.5 3.0 3.5 4.02.01.51.0
1.0
2.0
3.0
4.0
5.0
6.0
H (m)
( /h)
3
m
(l/s)
Pump Curves
Graph 2 - Pump performance curves
8

INSTALLATION – GENERAL
PIPE FITTINGS
The connection points to the heating system are in 22mm copper pipe on 120, 150, 170 and 210 litre units. On units 250
litres and above the primary ow connection is 28mm, the ow connections to central heating (CH) zones 22mm and the
domestic hot water (DHW) return connection 22mm copper pipe. The use of appropriately sized COMPRESSION FITTINGS
is recommended when connecting to the PremierPlus SystemFit pipes. Solder ttings can be used, but extreme care must
be taken to ensure the plastic coating of the unit casing is not damaged by heat. Push t type ttings can be used for
connection to the copper pipes.
The inlet connection to the cold water combination valve is 22mm compression. The PremierPlus SystemFit outlet tting
is suitable for connection to 22mm o/dia pipe (compression nut and olive supplied). The outlet is also threaded 3/4” BSP
male parallel should threaded pipe connections be preferred.
COLD FEED
A 22mm cold water supply is recommended, however, if a 15mm (1/2”) supply exists which provides sufcient ow, this may
be used. More ow noise may be experienced from small bore pipes due to the increased water velocity through them.
A stopcock or servicing valve should be incorporated into the cold water supply to enable the PremierPlus SystemFit and its
associated controls to be isolated and serviced.
PRESSURE REDUCING VALVE (Fig 2 below)
The 3.5 bar pressure reducing valve can be connected anywhere on the cold water mains supply prior to the PremierPlus
SystemFit unit. There is no requirement to site it close to the unit, it can be located at a point where the mains supply
enters the premises if this is more convenient but you must install a non-return valve just after the reducing valve for ease
of maintenance.
Fig 2 - Pressure reducing valve Fig 3 - Pressure relief valve (6 bar)
PRESSURE RELIEF VALVE (Fig 3 above)
Should a balanced pressure cold water supply be required to cold water outlets such as thermostatic shower mixer valves
or combination taps, the cold water balanced draw off connection should be taken from between the pressure reducing
valve and the pressure relief valve (see Fig 3 above). Branches to cold drinking water outlets should be taken directly from
the mains supply.
EXPANSION VESSEL
The expansion vessel accommodates expansion that results from heating the water inside the unit. The expansion vessel is
pre-charged at 3.5 bar. The expansion vessel must be connected between the expansion valve (see Fig. 3 above) and the
PremierPlus SystemFit cylinder. The location of the expansion vessel should allow access to recharge the pressure as and
when necessary, this can be done using a normal car foot pump. It is recommended that the expansion vessel is adequately
supported. An expansion vessel wall mounting bracket is supplied for this purpose and should be tted.
TUNDISH
The tundish must not be installed directly over any electrical device.
9
Outlet to cylinder
Mains in
22mm compression connection
Take note of flow
direction
Pressure reducing valve
cartridge (3 bar)
22mm compression connection
Outlet to cylinder
From cold water
combination
valve
Take note of ow
direction
Pressure relief valve
discharge connection
Pressure relief valve
“TEE” (incorporates
check valve)

10
DRAIN TAPS
Drain taps are tted to both the primary system pipework and to the cold water inlet to facilitate draining the unit or indirect
heating circuit for maintenance purposes. It is recommended that the outlet point of the drain pipe work be at least 1 metre
below the level of the heater (this can be achieved by attaching a hose pipe to the drain tap outlet spigot).
HOT WATER OUTLET
Ideally the pipework from the PremierPlus SystemFit to the outlet ttings should be in 22mm pipe with short runs of 15mm
pipe to showers and basin taps. Small bore pipe can also be used to suit some taps, but runs should be of minimum length.
Pipe sizes may vary due to system design.
SECONDARY CIRCULATION
If secondary circulation is required it is recommended that it be connected to the PremierPlus SystemFit cylinder as shown
in Fig 4 below via a swept tee joint into the cold feed to the unit. A swept tee joint is available as an accessory (order code
no. 94 970 033).
The secondary return pipe should be in 15mm pipe and incorporate a check valve to prevent backow. A suitable WRAS
approved bronze circulation pump will be required. On large systems, due to the increase in system water content, it may be
necessary to t an additional expansion vessel to the secondary circuit. This should be done if the capacity of the secondary
circuit exceeds 10 litres.
Pipe capacity (copper):
15mm O.D. = 0.13 l/m (10 litres = 77m)
22mm O.D. = 0.38 l/m (10 litres = 26m)
28mm O.D. = 0.55 l/m (10 litres = 18m)
WARNINGS
i) Under no circumstances should the factory tted temperature/pressure relief valve be removed other than by authorised
Santon personnel. To do so will invalidate any guarantee or claim.
ii) The cold water combination valve must be tted to the mains water supply to the PremierPlus SystemFit unit.
iii) No control or safety valves should be tampered with.
iv) The discharge pipe should not be blocked or used for any other purpose.
Cold inlet
connection
Check
valve
Secondary
circulation
pump
Swept
tee
Cold
supply
Secondary
return
Fig 4 - Secondary circulation connection

11
Tundish
Balanced cold water draw-off 6 Bar Pressure Relief
Valve (combined Expansion Relief Valve/Check Valve)
3.5 Bar Pressur
e Reducing
Valve incorporating Pressure Reducing Valve, Strainer,and Check Valve. (Stop cock can be fitted here)
MCWS to Kitchen (unbalanced cold mains supply)
Incoming Cold Water Main
KEY MCWS =
Mains cold water supply
HWS =
Hot water service
SC =
Stop Cock / Isolating Valve
DOC = Drain Off Cock
Discharge pipe to atmosphere
Isolating/Regulating Valves, as required
Temperature/Pressure Relief Valve
HWS supply
Balanced HWS and
MCWS to bathrooms, showers, cloakrooms, etc
DOC DOC
DOC
DOC
SC
SC
PremierPlus SystemFit
Fig 5 - Schematic installation diagram showing pressure reducing valve, pressure relief valve and positioning of cold balance
draw off.

12
INSTALLATION - DISCHARGE
It is a requirement of Building Regulation G3 that any discharge from an unvented system is conveyed to where it is visible,
but will not cause danger to persons in or about the building. The tundish and discharge pipes should be tted in accordance
with the requirements and guidance notes of Building Regulation G3. The G3 Requirements and Guidance section 3.50 -
3.63 are reproduced in the following sections of this manual. For discharge pipe arrangements not covered by G3 Guidance
advice should be sought from your local Building Control Ofcer. Any discharge pipe connected to the pressure relief devices
(Expansion Valve and Temperature/Pressure Relief Valve) must be installed in a continuously downward direction and in a
frost free environment.
Water may drip from the discharge pipe of the pressure relief device. This pipe must be left open to the atmosphere. The
pressure relief device is to be operated regularly to remove lime deposits and to verify that it is not blocked.
G3 REQUIREMENT
“...there shall be precautions...to ensure that the hot water discharged from safety devices is safely conveyed to where it is
visible but will not cause danger to persons in or about the building.”
Notes:
Discharge pipe-work D2 can now be a plastic pipe but only pipes that have been tested to a minimum 110°C must be
used.
Discharge pipe D2 can now be plumbed into the soil stack but only soil stacks that can handle temperatures of 99°C or
greater should be used.
The following extract is taken from the latest G3 Regulations
Discharge pipe D1
3.50 Safety devices such as temperature relief valves or combined temperature and pressure and pressure relief valves (see
paragraphs 3.13 or 3.18) should discharge either directly or by way of a manifold via a short length of metal pipe (D1) to a
tundish.
3.51 The diameter of discharge pipe (D1) should be not less than the nominal outlet size of the temperature relief valve.
3.52 Where a manifold is used it should be sized to accept and discharge the total discharge form the discharge pipes
connected to it.
3.53 Where valves other than the temperature and pressure relief valve from a single unvented hot water system dischargeby
way of the same manifold that is used by the safety devices, the manifold should be factory tted as part of the hot water
storage system unit or package.
Tundish
3.54 The tundish should be vertical, located in the same space as the unvented hot water storage system and be tted as
close as possible to, and lower than, the valve, with no more than 600mm of pipe between the valve outlet and the tundish
(Fig. 6 & Table 3, page 14).
Note: To comply with the Water Supply (Water Fittings) Regulations, the tundish should incorporate a suitable air gap.
3.55 Any discharge should be visible at the tundish. In addition, where discharges from safety devices may not be apparent,
e.g. in dwellings occupied by people with impaired vision or mobility, consideration should be given to the installation of
a suitable safety device to warn when discharge takes place, e.g. electronically operated.
Discharge pipe D2
3.56 The discharge pipe (D2) from the tundish should:
(a) have a vertical section of pipe at least 300mm long below the tundish before any elbows or bends in the pipework (see
Diagram 1, G3), (Fig. 6, page 14); and
(b) be installed with a continuous fall thereafter of at least 1 in 200.
3.57 The discharge pipe (D2) should be made of:
(a) metal; or
(b) other material that has been demonstrated to be capable of safely withstanding temperatures of the water discharged
and is clearly and permanently marked to identify the product and performance standard (e.g. as specied in the relevant
part of BS 7291).
3.58 The discharge pipe (D2) should be at least one pipe size larger than the nominal outlet size of the safety device unless
its total equivalent hydraulic resistance exceeds that of a straight pipe 9m long, i.e. for discharge pipes between 9m and
18m the equivalent resistance length should be at least two sizes larger than the nominal outlet size of the safety device;
between 18 and 27m at least 3 sizes larger, and so on; bends must be taken into account in calculating the ow resistance.
(See Diagram 1, Table 1, G3), (Fig. 6 & Table 3, page 14) and the worked example.

13
Note: An alternative approach for sizing discharge pipes would be to follow Annex D, section D.2 of BS 6700:2006
Specication for design, installation, testing and maintenance of services supplying water for domestic use within buildings
and their curtilages.
3.59 Where a single common discharge pipe serves more than one system, it should be at least one pipe size larger than
the largest individual discharge pipe(D2) to be connected.
3.60 The discharge pipe should not be connected to a soil discharge stack unless it can be demonstrated that that the
soil discharge stack is capable of safely withstanding temperatures of the water discharged, in which case, it should:
(a) contain a mechanical seal, not incorporating a water trap, which allows water into the branch pipe without allowing
foul air from the drain to be ventilated through the tundish;
(b) be a separate branch pipe with no sanitary appliances connected to it;
(c) if plastic pipes are used as branch pipes carrying discharge from a safety device they should be either polybutalene
(PB) to Class S of BS 7291-2:2006 or cross linked polyethylene (PE-X) to Class S of BS 7291-3:2006; and
(d) be continuously marked with a warning that no sanitary appliances should be connected to the pipe.
Note:
1. Plastic pipes should be joined and assembled with ttings appropriate to the circumstances in which they are used as
set out in BS EN ISO 1043-1.
2. Where pipes cannot be connected to the stack it may be possible to route a dedicated pipe alongside or in close proximity
to the discharge stack.
Termination of discharge pipe
3.61 The discharge pipe (D2) from the tundish should terminate in a safe place where there is no risk to persons in the
vicinity of the discharge.
3.62 Examples of acceptable discharge arrangements are:
(b) to a trapped gully with the end of the pipe below a xed grating and above the water seal;
(c) downward discharges at low level; i.e. up to 100mm above external surfaces such as car parks, hard standings, grassed
areas etc. are acceptable providing that a wire cage or similar guard is positioned to prevent contact, whilst maintaining
visibility; and
(d) discharges at high level: e.g. into a metal hopper and metal downpipe with the end of the discharge pipe clearly visible
or onto a roof capable of withstanding high temperature discharges of water and 3m from any plastic guttering system
that would collect such discharges.
3.63 The discharge would consist of high temperature water and steam. Asphalt, roong felt and non-metallic rainwater
goods may be damaged by such discharges.
Worked example of discharge pipe sizing
Fig. 6, page 14: shows a G1/2 temperature relief valve with a discharge pipe (D2) having 4 No. elbows and length of 7m
from the tundish to the point of discharge.
From Table 3, page 14:
Maximum resistance allowed for a straight length of 22mm copper discharge pipe (D2) from a G1/2
temperature relief valve is 9.0m.
Subtract the resistance for 4 No. 22mm elbows at 0.8m each = 3.2m
Therefore the permitted length equates to: 5.8m
5.8m is less than the actual length of 7m therefore calculate the next largest size.
Maximum resistance allowed for a straight length of 28mm pipe (D2) from a G1/2 temperature relief valves equates to
18m.
Subtract the resistance of 4 No. 28mm elbows at 1.0m each = 4.0m
Therefore the maximum permitted length equates to: 14m
As the actual length is 7m, a 28mm (D2) copper pipe will be satisfactory.
WARNINGS:
• Under no circumstances should the factory tted temperature/pressure relief valve be removed other than by a competent
person. To do so will invalidate any guarantee or claim.
• The cold water combination valve assembly must be tted on the PremierPlus SystemFit water supply to the PremierPlus
SystemFit cylinder.
• No control or safety valves should be tampered with or used for any other purpose.
• The discharge pipe should not be blocked or used for any other purpose.
• The tundish should not be located adjacent to any electrical components.

14
Table 3 - Sizing of copper discharge pipe (D2) for common temperature relief valve outlet sizes
600mm maximum
300mm
minimum
Safety device
(e.g. Temperature
relief valve) Metal discharge pipe (D1) from
Temperature relief valve to tundish
Tundish
Discharge below
xed grating
(Building Regulation
G3 section 3.61 gives
alternative points
of discharge)
Fixed grating
Trapped
gully
Discharge pipe (D2 from tundish,
with continuous fall. See Building
Regulation G3 section 3.56,
Table 4 and worked example)
VALVE OUTLET
SIZE
MINIMUM SIZE
OF DISCHARGE
PIPE D1
MINIMUM SIZE
OF DISCHARGE
PIPE D2 FROM
TUNDISH
MAXIMUM
RESISTANCE
ALLOWED,
EXPRESSED AS
A LENGTH OF
STRAIGHT PIPE
(i.e. NO ELBOWS
OR BENDS)
RESISTANCE
CREATED BY
EACH ELBOW OR
BEND
G 1/2 15mm
22mm
28mm
35mm
UP TO 9m
UP TO 18m
UP TO 27m
0.8m
1.0m
1.4m
G 3/4 22mm
28mm
35mm
42mm
UP TO 9m
UP TO 18m
UP TO 27m
1.0m
1.4m
1.7m
G1 28mm
35mm
42mm
54mm
UP TO 9m
UP TO 18m
UP TO 27m
1.4m
1.7m
2.3m
NOTE: The above table is based on copper tube. Plastic pipes may be of different bore and resistance. Sizes and maximum
lengths of plastic should be calculated using data prepared for the type of pipe being used.
Fig. 6: Typical discharge pipe arrangement (extract from Building Regulation G3 Guidance section 3.5)

15
INSTALLATION - PRIMARY CIRCUIT
BOILER SELECTION
• The PremierPlus SystemFit models are suitable for use with most gas, oil red or electric boilers compatible with unvented
systems i.e. tted with a temperature control thermostat and thermal cut-out.
• If in doubt consult the boiler manufacturer.
• Solid fuel boilers or any other boiler in which the energy input is not under effective thermostatic control unless additional
and appropriate safety measures are installed should NOT be used.
• The boiler used can either be a sealed system or open vented type, maximum primary circuit pressure 3 bar.
• The primary ow from the boiler MUST be pumped. Gravity circulation will not work due to the special design of the
primary heat exchanger.
• The boiler ow temperature should usually be set to 82°C (maximum ow temperature to primary heat exchanger
90°C).
• The boiler cannot be vented through the PremierPlus SystemFit unit.
INDIRECT THERMAL CUT-OUT AND 2-PORT MOTORISED VALVE
To comply with Building Regulations and to prevent the PremierPlus SystemFit from overheating the 2-Port motorised valve
supplied tted to the primary ow to the indirect coil MUST NOT be removed or bypassed. This valve is factory wired in
series with the indirect thermal cut-out such that the primary ow to the heating coil is interupted should the PremierPlus
SystemFit unit overheat.
WIRING
All electrical wiring should be carried out by a competent electrician and be in accordance with the latest I.E.E. Wiring
Regulations.
The PremierPlus SystemFit indirect thermostat and thermal cut-out, primary circulating pump and motorised valves are
factory pre-wired. Further wiring will be required between the wiring centre, the programmer, room temperature sensor
and the boiler (Fig 8, page 17). Additional controls and wiring will be required if a second CH zone is to be tted to the
instalation.
The indirect thermal cut-out MUST NOT be bypassed.
HEATING SYSTEM CONTROLS
The controls provided with the PremierPlus SystemFit will ensure the safe operation of the unit within a central heating
system.
Connection to the various system components is made via the wiring centre tted to the front of the PremierPlus SystemFit,
refer to gure 8, page 17 and the terminal identication labels within the wiring centre to aid in connecting the various
external system components such as the mains supply, programmer and boiler. The wiring to the external components is
made using exible cable, this should be secured using the integral cable grips located in the wiring centre.
Provision is made for the connection of a second CH zone (connection pipe supplied blanked off). Additional controls will
be necessary to control the operation of the second CH zone, usually a second 28mm CH zone valve and a programmable
room thermostat. Connection terminals are provided and identied in the wiring centre to enable any wiring to be connected
to the same central position.
The mains supply must be via a double pole isolating switch with a contact separation of at least 3mm in both poles. The
supply must be fused 3 amp. A supply cable of 1.0 to 1.5mm2cross sectional area should be used.

16
Fig 7 - Adjustment details
PROGRAMMER AND ROOM TEMPERATURE SENSOR
The programmer and room temperature sensor are supplied loose such that they can be installed at a convenient location
within the property. These items are supplied with their own installation and user instruction leaet which should be
referred to for details of mounting, wiring and programming. NOTE: The room sensor is wired directly to the programmer
not to the wiring centre. The room sensor must be used, it is not possible to integrate a standard room thermostat with
the programmer. Temperature setting of the room temperature is also done at the programmer, there is no adjustment at
the room temperature sensor. Temperature setting of the stored water in the PremierPlus SystemFit is done at the indirect
thermostat housed within the indirect terminal housing on the front of the PremierPlus SystemFit unit.
Basic Programmer Features:
• 24 hour or 5/2 day operation
• Room temperature setting at programmer
• Set temperature over-ride facility
• 1 hour hot water boost facility
• Battery back up retains programmed information in the event of a power interuption
• Low temperature set back option for periods when the property is unoccupied, eg. holiday periods
• Independent time control of central heating and domestic hot water (Building Regulation Part L1 compliant)
NOTE: The programmer supplied will only provide control for one CH zone. Should a second CH zone be required, additional
controls will be needed (not supplied) to fulll the requirements of Building Regulation Part L1.
Thermal cut-out reset button
Spindle positions
= Minimum temp 10°C
= Maximium temp 72°C
= Approx 60°C
Rotate spindle clockwise
for temperature increase
and counter-clockwise
for temperature decrease
Temperature adjusting
spindle

17
Fig 8 - Schematic wiring diagram - Indirect circuit
KEY
Br BROWN
Bl BLUE
G GREY
O ORANGE
W WHITE
GY GREEN/YELLOW
DHW DOMESTIC HOT WATER
HTG HEATING
L LIVE
N NEUTRAL
EARTH
BOILER
(DHW)
ZONE VALVE
WIRING CENTRE
12345678910
L N
G
Br Bl O
GY
2
13
L N
L
N
PUMP
INDIRECT
THERMAL CONTROLS
(SUPPLIED FITTED)
FUSED (3 AMP)
MAINS SUPPLY
N.B. A DOUBLE POLE ISOLATING
SWITCH MUST BE INSTALLED IN
THE MAINS SUPPLY
NOTES
1. ALL EARTH CONNECTIONS MUST BE LINKED BACK TO THE EARTH TERMINALS IN THE WIRING CENTRE
2. ALL NEUTRAL CONNECTIONS MUST BE LINKED BACK TO THE NEUTRAL TERMINALS IN THE WIRING CENTRE
3. ASSUMES BASIC BOILER
4. THE 22MM MOTORISED VALVES DO NOT HAVE A WHITE WIRE
5. THE ABOVE DIAGRAM IS FOR GUIDANCE ONLY, SANTON ACCEPT NO LIABILITY FOR ANY LOSS OR DAMAGE ARISING FROM
ANY ERRORS OR OMISSIONS THAT MAY BE INADVERTENTLY CONTAINED WITHIN THIS DIAGRAM. THE VARIOUS EQUIPMENT
MANUFACTURERS SHOULD BE CONSULTED TO CONFIRM THE CORRECT OPERATION OF THEIR PRODUCTS WITHIN THE SYSTEM
11 13
12 14 15 16
N
N
N
N
(SUPPLIED FITTED)
(SUPPLIED FITTED)
PROGRAMMER - HEATING ZONE 1
& DOMESTIC HOT WATER
(SUPPLIED)
L N
HTG DHW
ON ON
4 3 5 6
ROOM SENSOR
(SUPPLIED)
N
(SUPPLIED FITTED)
HEATING ZONE 1VALVE
G
Br Bl O
GY
N
(SUPPLIED FITTED)
W
HEATING ZONE 2 VALVE
G
Br Bl O
GY
N
(NOT SUPPLIED)
W
PROGRAMMABLE
ROOM THERMOSTAT
FOR ZONE 2
(NOT SUPPLIED)
12

18
COMMISSIONING
At the time of commissioning, please ensure all relevant sections of the Benchmark Checklist, (Pages 26 and 27) of this
document are completed.
FILLING THE UNIT WITH WATER
• Check expansion vessel pre-charge pressure. The vessel is supplied precharged to 3.5 bar to match the control pressure
of the pressure reducing valve. The precharge pressure is checked using a car tyre gauge by unscrewing the plastic cap
opposite the water connection.
• Check all connections for tightness including the immersion heater(s). An immersion heater key spanner is supplied for
this purpose.
• Ensure the drain cock is CLOSED.
• Open a hot tap furthest from the PremierPlus SystemFit cylinder.
• Open the PremierPlus SystemFit stop cock to ll the unit. When water ows from the tap, allow to run for a few minutes
to thoroughly ush through any residue, dirt or swarf, then close the tap.
• Open successive hot taps to purge the system of air.
SYSTEM CHECKS
• Check all water connections for leaks and rectify as necessary.
• Turn off PremierPlus SystemFit water supply.
• Remove the pressure reducing valve head work to access the strainer mesh, clean and re-t.
• Manually open, for a few seconds, each relief valve in turn, checking that water is discharged and runs freely through
the tundish and out at the discharge point.
• Ensure that the valve(s) reseat satisfactorily.
INDIRECT (PRIMARY) CIRCUIT
Fill the indirect (primary) circuit following the boiler manufacturer’s commissioning instructions. To ensure the primary
heating system is correctly lled the 2-port motorised valves should be manually opened by moving the lever on the motor
housings to the MANUAL OPEN setting. When the primary circuit is full return the levers to the AUTO position. Vent any
trapped air. Check the primary system for leaks and rectify as necessary. Flush the primary system in accordance with the
boiler manufacturers instructions and add a suitable inhibitor when re-lling.
Switch on the electrical supply to the PremierPlus SystemFit indirect controls and the boiler. Programme the PremierPlus
SystemFit controller as detailed in the tting and user instruction leaet supplied with the controller. Set the controller for
hot water operation only (the +1HR ON Hot Water over-ride button can be used if the time is during a hot water OFF period).
Check that the heating 2-port motorised valve is closed and that the hot water 2-port motorised valve opens. The pump
should run and the boiler re (tap symbol appears in controller display). The primary ow to the PremierPlus SystemFit
should become hot, if it does not, check for a wiring or piping error.
Allow the PremierPlus SystemFit unit to heat up and check that the hot water thermostat and 2-port motorised valve operate
correctly. A storage temperature of approx. 60°C is recommended (see Fig 7, page 16 for adjustment details). If necessary
the temperature can be adjusted by inserting a at bladed screwdriver in the adjustment knob and rotating. The minimum
thermostat setting is 10°C. The adjustment range on the spindle represents a temperature range of 10° to 72°C.
Select the heating only function on the controller. NOTE: The room temperature is set at the controller, no adjustment is
possible at the room sensor unit. Check that the heating 2-port motorised valve opens and that the hot water 2-port motorised
valve is closed. The pump should run and the boiler re (a ame symbol appears in the controller display). The primary ow
to the PremierPlus SystemFit and the radiator circuit should become hot, if it does not check for a wiring or piping error.
If a second CH zone is tted, adjust the programmable room thermostat so that it is calling for heat. Check that the second
CH zone valve opens. The pump should run and the boiler re. The primary ow to the second CH zone should become
hot, if it does not check for a wiring or piping error.
Select the heating and hot water control function on the controller. Check that the heating 2-port motorised valve and the
hot water 2-port motorised valve open.
The minimum thermostatic setting is 10 °C. The maximum thermostatic setting is 72 °C.

19
NOTE: it may be necessary to cool the PremierPlus SystemFit down to allow the indirect thermostat to call for heat, it
may also be necessary to increase the required room temperature setting if the room temperature has already reached
that programmed. The pump should run and the boiler re (both a tap symbol and a ame symbol should appear in the
controller display). The primary ow to the Premier Plus SystemFit and the radiator circuit should become hot. If it does
not, check for a wiring or piping error.
When the heating and hot water temperatures are reached, the 2-port motorised valves should close, the pump stops
running and the boiler stops ring. NOTE: If a pump over-run boiler is tted, the pump may continue to run for a short
time after the boiler has shut down.
Check that no water is discharged from either the expansion valve or temperature and pressure relief valve during the heating
cycle. If the user temperatures or “On” and “Off” times have been adjusted for commissioning purposes, the controller
should be reset to the desired settings. The operation of the controller should be demonstrated to the user and the controller
installation and user instructions left with them for future reference.
AUTOMATIC SYSTEM BY-PASS
An automatic differential bypass valve is tted to the PremierPlus SystemFit. This has been factory set to an optimum position
for most domestic heating systems. However, in some systems it may require further adjustment. To do this:
Turn the adjustment spindle fully clockwise such that the 0.5 marking is level with the top of the valve body.
Turn on the system and set the controller to heating only. Balance the system in the normal manner.
With the boiler ring and the pump running, slowly turn the adjustment knob anti-clockwise until hot water can be felt on
the outlet side of the bypass valve. Turn the adjustment knob clockwise by half a turn.
MAINTENANCE
MAINTENANCE REQUIREMENTS
Unvented hot water systems have a continuing maintenance requirement in order to ensure safe working and optimum
performance. It is essential that the relief valve(s) are periodically inspected and manually opened to ensure no blockage
has occurred in the valves or discharge pipework. Similarly cleaning of the strainer element and replacement of the air in
the expansion vessel will help to prevent possible operational faults.
The maintenance checks described below should be performed by a competent person on a regular basis, e.g. annually to
coincide with boiler maintenance.
After any maintenance, please complete the relevant service interval record section of the Benchmark Checklist on page 27
of this document.
INSPECTION
The immersion heater boss can be used as an access for inspecting the cylinder internally.
SAFETY VALVE OPERATION
Manually operate the temperature/pressure relief valve for a few seconds. Check water is discharged and that it ows freely
through the tundish and discharge pipework. Check valve reseats correctly when released. NOTE: Water discharged may
be very hot!
Repeat the above procedure for the expansion relief valve.
STRAINER
Turn off the cold water supply, boiler and immersion heaters. The lowest hot water tap should then be opened to de-pressurise
the system. Remove the pressure reducing cartridge to access the strainer mesh. Wash any particulate matter from the strainer
under clean water. Re-assemble ensuring the seal is correctly tted. DO NOT use any other type of sealant.
DESCALING IMMERSION HEATER(S)
Before removing the immersion heater(s), the unit must be drained. Ensure the water, electrical supply and boiler are OFF before
draining. Attach a hosepipe to the drain cock having sufcient length to take water to a suitable discharge point below the
level of the unit. Open a hot tap close to the unit and open the drain cock to drain the unit.

IMMERSION HEATER REMOVAL
Open the cover(s) to the immersion heater housing(s) and disconnect wiring from immersion heater thermostat(s). Remove
thermostat capillary sensors from the pockets on the immersion heater. Unscrew immersion heater backnut(s) and remove
immersion heater from the unit. A key spanner is supplied with the cylinder unit for easy removal/tightening of the backnut(s).
Over time, the immersion heater gasket may become stuck to the mating surface. To break the seal, insert a round bladed
screwdriver into one of the pockets on the immersion heater and gently lever up and down.
Carefully remove any scale from the surface of the element(s). DO NOT use a sharp implement as damage to the element
surface could be caused. Ensure sealing surfaces are clean and seals are undamaged, if in doubt t a new gasket
(part number 95 611 822).
Replace immersion heater(s) ensuring the lower (right angled) element hangs vertically downwards towards the base of the
unit. It may be helpful to support the immersion heater using a round bladed screwdriver inserted into one of the thermostat
pockets whilst the backnut is tightened. Replace thermostat capillaries into pocket. Replace the immersion heater thermostat
by carefully plugging the two male spade terminations on the underside of the thermostat head into the corresponding
terminations on the element. Rewire, check, close and secure immersion heater housing cover(s).
EXPANSION VESSEL CHARGE PRESSURE
Remove the dust cap on top of the vessel. Check the charge pressure using a tyre pressure gauge. The pressure (with system
de-pressurised) should be 0.35MPa (3.5 bar). If it is lower than the required setting it should be re-charged using a tyre pump
(Schrader valve type). DO NOT OVER-CHARGE. Re-check the pressure and when correct replace the dust cap.
RE-COMMISSIONING
Check all electrical and plumbing connections are secure. Close the drain cock. With a hot tap open, turn on the cold water
supply and allow unit to rell. DO NOT switch on the immersion heater(s) or boiler until the unit is full. When water ows
from the hot tap, allow to ow for a short while to purge air and ush through any disturbed particles. Close hot tap and
then open successive hot taps in the system to purge any air. When completely full and purged, check system for leaks. The
heating source (immersion heater(s) or boiler) can then be switched on.
BENCHMARK LOG BOOK
On completion of any maintenance or service of the PremierPlus SystemFit, the Benchmark “Installation, Commissioning
and Service Record Log Book” should be lled in to record the actions taken and the date the work was undertaken.
USER INSTRUCTIONS
WARNINGS
IF WATER ISSUES FROM THE TEMPERATURE/PRESSURE RELIEF VALVE ON THE PREMIERPLUS SYSTEMFIT CYLINDER SHUT
DOWN THE BOILER. DO NOT TURN OFF ANY WATER SUPPLY. CONTACT A COMPETENT INSTALLER FOR UNVENTED WATER
HEATERS TO CHECK THE SYSTEM.
DO NOT TAMPER WITH ANY OF THE SAFETY VALVES FITTED TO THE PREMIERPLUS SYSTEMFIT. IF A FAULT IS SUSPECTED,
CONTACT A COMPETENT INSTALLER.
BENCHMARK
The PremierPlus SystemFit cylinder is covered by the Benchmark Scheme which aims to improve the standards of installation
and commissioning of domestic heating and hot water systems in the UK and to encourage regular servicing to optimise
safety, efciency and performance.
Benchmark is managed and promoted by the Heating and Hotwater Industry Council. For more information visit www.
centralheating.co.uk.
Please ensure that the installer has fully completed the Benchmark Checklist (page 26 and 27) of this manual and that you
have signed it to say that you have received a full and clear explanation of its operation. The installer is legally required
to complete a commissioning checklist as a means of complying with the appropriate Building Regulations (England and
Wales).
All installations must be notied to Local Area Building Control either directly or through a Competent Persons Scheme. A
Building Regulations Compliance Certicate will then be issued to the customer who should, on receipt, write the Notication
Number on the Benchmark Checklist.
This product should be serviced regularly to optimise its safety, efciency and performance. The service engineer should
complete the relevant Service Record on the Benchmark Checklist after each service.
20