EHC NEPTUNE NINDSL90L Installation and operating instructions

Installation & Maintenance
Instructions
MARCH 2017
The Electric Heating Company Ltd
Unit 40 Block 5 Third Road
Blantyre Industrial Estate
Blantyre Glasgow
G72 0UP
Tel: [phone]
Fax: [phone]
email: [e-mail]
www.electric-heatingcompany.co.uk

01 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS
PAGE CONTENT
1 Introduction
2 Storage, Handling & Supply Requirements
3 Component Table
4 Siting the unit
5 General Installation
7 Discharge Arrangement
9 Technical Specifications: Slimline -
Direct & Indirect
10 Technical Specifications: Direct & Indirect
11 Technical Specifications: Solar Indirect
12 Solar Coil Installation
13 S-Plan Wiring Schematics
14 Commissioning & Servicing
15 Fault Finding & User Instructions
16 - 17 Specification & Performance
18 Commissioning Record
19-24 Service Record
25-26 Guarantee - Terms & Conditions
27 Gaurantee Card
INTRODUCTION
The EHC Neptune Unvented cylinder is made from
Duplex Stainless Steel for excellent corrosion resistance.
The EHC Neptune has a strong rust-resistant steel case
and is highly insulated with environmentally friendly
foam.
The EHC Neptune is supplied complete with all the
necessary safety and control devices needed to connect
to the cold water mains. All are pre-adjusted. High
quality controls have been selected to combine high flow
rate performance with minimum pressure drop to make
the EHC Neptune perform well in all areas, even those
with poor water pressure.
IMPORTANT NOTE TO
THE INSTALLER
Read these instructions before commencing installation. Unvented cylinders are a controlled service as defined in the
latest edition of the building regulations and should only be fitted by a competent person.
The relevant regulations are: England and Wales – Building Regulation G3, Scotland – Technical Standard P3, N Ireland –
Building Regulation Part F
After installation the commissioning record must be completed and left, with these instructions, with the householder for
future reference.
IMPORTANT NOTE TO THE INSTALLER
Read these instructions before commencing installation. Unvented cylinders are a controlled
service as defined in the latest edition of the building regulations and should only be fitted
by a competent person.
The relevant regulations are: England and Wales – Building Regulation G3, Scotland – Technical
Standard P3, N Ireland – Building Regulation Part F
After installation the commissioning record list must be completed and left, with these
instructions, with the householder for future reference.

02
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS
STORAGE PRIOR TO INSTALLATION
The EHC Neptune should be stored in its original packaging
in an upright position in an area free from excessive damp.
Regulations G3+L.
HANDLING PRODUCT
The EHC Neptune should be carried upright where possible.
Assessments of risks for carrying the cylinder should be
conducted. Use more than 1 person for carrying where
appropriate. Always follow latest guidelines for lifting
techniques, to avoid injury and damage to the product.
WATER SUPPLY
The EHC Neptune operates at 3 bar (controlled by the inlet
control set) and is capable of delivering over 50 litres per
minute. The high quality inlet control set has been designed
to make the most of the flow rates available, however the
performance of any unvented system is only as good as the
mains water supply. The maximum possible water demand
should be assessed, taking into consideration that both
hot and cold services are supplied simultaneously from the
mains.
The water supply should be checked to ensure it can
meet these requirements. If necessary, consult the local
water company regarding the likely pressure and flow rate
availability.
If measuring the water pressure, note that a high static
(no flow) mains pressure is no guarantee of good flow
availability. In a domestic installation 1.5 bar and 25 l/min.
should be regarded as the minimum. The maximum mains
pressure that the inlet control set can accept is 12 bar.
Consideration should be given to upgrading existing
½” (15mm) cold mains pipework to a larger size if the
recommended minimum pressure/flow rate is not being
achieved.
ELECTRIC SUPPLY
The EHC Neptune requires 240 Volt electrical supply for
the immersion elements. The electrical supply to each
immersion heater must be fused at 13A via a double pole
isolating switch to BS 3456. The cable must be at least
2.5mm2heat resistant (85°C HOFR) sheathed flex complying
to BS 6141:1981 Table 8.
UNPACKING THE UNIT
The EHC Neptune comes complete with the fittings required
to complete the installation. Please see over for component
content list.
High flow rate inlet control set - 3 bar
PRV 6 bar Expansion Relief
Spare Part No. CB091
Temperature and pressure relief valve
Spare Part No. CB098
Acetal tundish 15 x 22 mm
Spare Part No. CB096
Incoloy long life
3 kW immersion heater
Spare Part No. CB099
Two port valve
Spare Part No. EC10008
Dual thermostat
Spare Part No. CB142
High limit thermostat
Spare Part No. CB135
Expansion Vessel
• 60- 250 ltr units - 18 ltr vessel
Spare Part No. CB144
• 300 ltr units - 25 ltr vessel
Spare Part No. CB145

COMPONENT CONTENT TABLE
Inlet Control Set ••••• Temp & Pressure Relief Valve • • • • • Tundish ••••• Expansion Vessel ••••• Immersion Heater • • • • • Two Port Valve • • • Dual Thermostat • • • Single High Limit Stat • Sensor Pocket Retaining Bungs • Installation & Maintenance Instructions •••••
Slimline Direct Models (Electric)
Slimline Indirect Models
Direct Models (Electric)
Indirect Models
Solar Indirect Models
Direct Models (Electric)
Indirect Models (Single Coil)
Solar Indirect Models (Two Coils)
03 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

SITING THE UNIT
The EHC Neptune can supply outlets above it or at some
distance from it. Site the unit to minimise “dead leg”
distances, especially to the point of most frequent use.
Outlets above the EHC Neptune will reduce the outlet
pressure available by 0.1 bar for every 1m of height
difference. The unit should be protected from frost.
Particular care is needed if sitting in a garage or outbuilding.
All exposed pipework should be insulated. EHC Neptune
must be installed VERTICALLY on a flat base capable
of supporting the weight of the cylinder when full. See
technical specification section (page 16) for weights. The
minimum recommended cupboard size is 650mm square.
NOTES:
The pressure reducing
valve, non-return valve
and expansion relief valve
are combined together in
the inlet control set.
On 60 – 180 litre sizes
there is no dedicated
secondary return boss
and the secondary return
circuit should be tee’d into
the cold feed pipe just
above the drain elbow.
SCHEMATIC DIAGRAM
Access for maintenance of the valves should be considered.
Consideration should be given to position of discharge
pipes (tundish), drain valves - shall be positioned away from
electrical components.
The immersion heaters are 375mm long and care should be
taken to ensure that they can be withdrawn for servicing
if required. The discharge pipework from the safety valves
should fall continuously and terminate safely.
IMMERSION
HEATER
COLD
MAIN
ISOLATING
VALVE
PRESSURE
REDUCING
VALVE
NON
RETURN
VALVE
EXPANSION
RELIEF
VALVE
TUNDISH
TEMPERATURE
& PRESSURE
RELIEF VALVE
BALANCED
COLD
CONNECTION
COLD
INLET VIA
DRAIN
NON
RETURN
VALVE
BRONZE
PUMP
SECONDARY RETURN CIRCUIT
( 210, 250 & 300 L SIZES )
DUAL
STAT
2 PORT
VALVE
BOILER
FLOW
BOILER
RETURN
HOT OUTLET
EXPANSION
VESSEL
WITH WALL
BRACKET
04
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

GENERAL INSTALLATION
COLD MAINS PIPEWORK
Run the cold main through the building to the place where
the EHC Neptune is to be installed. Take care not to run the
cold pipe near hot water or heating pipework so that the
heat pick-up is minimized. Identify the cold water supply pipe
and fit an isolating valve (not supplied).
A 22mm BS1010 stopcock can typically be used but a 22mm
quarter turn full bore valve would be better as it does not
restrict the flow as much. Do not use “screwdriver slot” or
similar valves. Make the connection to the cold feed of the
cylinder and incorporate a drain valve. Position the drain
valve no higher than the cold inlet to ensure sufficient
draining of cylinder when required. Position the inlet control
just ABOVE the Temperature & Pressure Relief Valve (TPRV)
mounted on the side of the cylinder. This ensures that
the cylinder does not have to be drained down in order to
service the inlet control set. Ensure that the arrow points
in the direction of the water flow. Select a suitable position
for the expansion vessel. Mount it to the wall using the
bracket attached to the vessel. Use suitable fittings capable
of supporting full vessel weight (and with appropriate
consideration to wall material). Connect the expansion
vessel to the cold feed pipework between the inlet control
set and the cold inlet on the cylinder. Ensure that the top of
the vessel is accessible for servicing.
CONNECTING TO THE CYLINDER
All of the pipework connections on the cylinder are 22mm
compression and supplied complete with gland nuts and
olives, in the Accessory Kit box. Only connect 22mm Table X
copper tube to these connections.
Cut the tube with a pipe cutter and ensure no sharp edges or
burrs protrude. Slide both gland nut and olive onto the tube
and push tube fully home into the connection, ensuring the
tube end fully bottoms on the connection recess. Smear the
outer wall of the olive with plumbing paste and tighten gland
nut in the prescribed manner. Upon filling/commissioning,
ensure all connections are completely watertight. Note:
No control or isolation valve should be fitted between the
expansion relief valve and the storage cylinder. The relief
valve connections should not be used for any other purpose.
(expansion vessel not to scale)
Turn to
test
Cold
Mains In
Balanced Cold
Connection
Outlet to Cylinder
Expansion
Relief to
Tundish
Expansion
Relief
Connection
05 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

BALANCED COLD CONNECTION
If there are to be showers, bidets or monobloc taps in the
installation then a balanced cold supply is necessary. There
is a 22mm balanced connection on the inlet set.
HOT WATER PIPEWORK
Run the first part of the hot water distribution pipework
in 22mm. This can be reduced to 15mm and 10mm as
appropriate for the type of tap etc. Your aim should be
to reduce the volume of the hot draw-off pipework to a
practical minimum so that the time taken for the hot water
is as quick as possible. Where monobloc mixing taps and
showers are used, these should be installed to comply with
the Water Supply (Water Fittings) Regulations 1999. If these
devices are supplied with un-balanced supplies there should
be single check valves installed at both inlets, to stop over
pressurising of either supply.
PRIMARY COIL CONNECTIONS FOR INDIRECT UNITS
For Solar input models refer to pages 11-12 before making
any connections.
Connect the primary connections (Indirect only) using the
compression connections provided. The primary circuit must
be positively pumped. Gravity circulation is not suitable.
Either primary connection may be used as the primary flow,
reheat times are not effected. The primary circuit can be
open vented or sealed, with up to a maximum pressure of 3.5
bar. If you seal the primary circuit an additional expansion
vessel and safety valve is required. The boiler may be Gas,
Electric or Oil but must be under effective thermostatic
control. Uncontrolled heat sources such as some AGA’s, back
boilers, solid fuel stoves, etc. are NOT SUITABLE. Please
contact our Technical department for guidance. Connect the
two port zone valve ( indirect only ) into the primary flow
pipework. The direction of flow arrow should be towards the
primary flow connection.
SECONDARY CIRCULATION
The EHC Neptune can be used with secondary circulation.
An appropriate WRAS approved bronze circulator should
be used in conjunction with a non-return valve to prevent
backflow. On large secondary circulation systems it may
be necessary to incorporate an extra expansion vessel into
the circuit to accommodate the increased system water
volume. Secondary circulation should be avoided on Direct
electrically heated units being used on off-peak electricity
tariffs.
A secondary return boss is fitted as standard on 210, 250
& 300 ltr units. On smaller sizes, tee into the cold feed pipe
above the drain.
IMMERSION HEATERS
Only immersion heaters with a thermal cut-out may be used.
To help ensure this, the immersion heaters have a special
1 3/4” thread. They are rated at 3kW at 240V and are of a low
noise Incoloy construction.
They have both a thermostat and a high limit cutout. Please
order the correct replacement via ourselves; fitting non-
approved immersions may affect your guarantee. When
fitting, ensure the ‘O’ ring is positioned correctly on the head
of the immersion heater and lubricate before fitting. Fit it
by hand until almost home then tighten gently as the ‘O’
rings will seal easily. The electrical supply to each immersion
heater must be fused at 13A via a double pole isolating
switch to BS 3456. The cable must be 2.5mm2heat resistant
(85°C HOFR) sheathed flex complying to BS 6141:1981 Table
8. Do not operate the immersion heater/s until the unit
is full of water. Do not operate the immersion heater/s if
any sterilisation liquid is in the cylinder as this will cause
premature failure.
ELECTRICAL CONNECTIONS
Complete the wiring – use the appropriate wiring diagrams
on page 12- 13.
06
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

DISCHARGE ARRANGEMENT
Position the inlet control group so that the discharge from
both safety valves can be joined together via a 15mm end
feed Tee (see diagram above). Connect the Tundish and
route the discharge pipe. The discharge pipework must
be routed in accordance with Part G3 of schedule 1 of the
Building Regulations. The information that follows is not
exhaustive and if you are in doubt you should seek advice.
The two safety valves will only discharge water under fault
conditions. When operating normally water will not be
discharged. The tundish should be vertical, located in the
same space as the unvented hot water storage system and
be fitted as close as possible to, and lower than, the safety
device, with no more than 600mm of pipe between the valve
outlet and the tundish. The tundish should be positioned
away from electrical devices.
Any Discharge should be visible at the tundish. The tundish
should be located such that any discharge is visible. In
addition, where discharges from safety devices may not
be apparent, e.g. 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.
Diagram of a typical discharge pipe arrangement (extract from
Building Regulation G3)
Note: The discharge will
consist of scalding water and
steam. Asphalt, roofing felt
and non-metallic rainwater
goods may be damaged by
such discharges.
Note: D2 pipe from tundish
is now allowed to be
installed in soil stacks within
premises. This activity is not
recommended as discharge
from T&P may continue for
long periods of time. It is
the installer’s responsibility
to ensure the discharge
pipework can support the
discharge for prolonged
periods.
If used follow guidance on
mechanical seal without
water trap given in G3
Building Regulations.
As discharge can be in
excess of 90oC discharge
into plastic pipework is also
not recommended.
07 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

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.
B) Be installed with a continuous fall of at least 1 in 200
thereafter.
The discharge pipe (D2) from the tundish should be of metal
or other material that have been demonstrated to be capable
of withstanding temperatures of the water discharged.
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. discharge pipes between 9m
and 18m 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 flow resistance.
Refer to diagram 1, Table 1 and the worked example. An
alternative approach for sizing discharge pipes would be to
follow BS670 ce of services supplying water for domestic
use within buildings and their curtilages.
The discharge pipe (D2) should terminate in a safe place
where there is no risk to persons in the vicinity of the
discharge. Examples of acceptable discharge arrangements
are:
a. To a trapped gully with the end of the pipe below
the fixed grating and above the water
seal.
b. Downward discharges at a low level; i.e. up to 100mm
above external surfaces such as car parks, hard standings,
grassed areas etc. are acceptable providing that where
children play or otherwise come into contact with
discharges, a wire cage or similar guard is positioned to
prevent contact whilst maintaining visibility.
c. Discharges at a high level; e.g. in to metal hopper
and metal down pipe 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 systems that would collect such discharges.
d. Device to warn when discharge takes place.
WORKED EXAMPLE
The example below is for 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 1:
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 maximum
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 valve equates to:
14m. As the actual length is 7m, a 28mm (D2) copper pipe
will be satisfactory.
TABLE 1
Sizing of copper discharge pipe ‘D2’ for a temperature
relief valve with a G1/2 outlet size (as supplied).
Size of
discharge
pipework
Maximum length of
straight pipe
(no bends or
elbows)
Deduct the figure below
from the maximum length
for each bend or elbow in the
discharge pipe
22mm Up to 9m 0.8m
28mm Up to 18m 1m
35mm Up to 27m 1.4m
08
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

EHC NEPTUNE SLIMLINE DIRECT
EHC NEPTUNE SLIMLINE INDIRECT
B
A
120.00
“ F PTRV BOSS
1
2
D A B C G
22mm HOT
DRAW - OFF
22mm SECONDARY
RETURN (not always fitted.
See table)
22mm COLD FEED WITH
DIP PIPE TO DEFLECTOR
IN BOTTOM OF CYLINDER
SECOND IMMERSION HEATER
40.0˚
45.0˚
15.0˚ 30.0˚
50.0˚
25.0˚
40.0˚
45.0˚
35.0˚
15.0˚
50.0˚
10.0˚
CODE HEIGHT DIAMETER A B C D G ERP
BAND
LOAD PROFILE kWH/Annum
NDIRSL90L 1048 478 175 210 610 N/F 858 D M 1461
NDIRSL120L 1236 478 175 210 710 N/F 1046 D M 1461
NDIRSL150L 1424 478 175 210 810 N/F 1234 D L 1778
NDIRSL180L 1 674 478 175 210 910 N/F 1484 D L 2791
NDIRSL210L 1987 478 175 210 1100 1500 1797 D L 2837
F D A B C G
22mm HOT
DRAW - OFF
22mm SECONDARY
RETURN (not always fitted.
See table)
“ F PTRV BOSS
1
2
22mm COLD FEED WITH
DRY STAT POCKET
DIP PIPE TO DEFLECTOR
IN BOTTOM OF CYLINDER
120.00
CODE HEIGHT DIAMETER A B C D F G ERP
BAND
STANDING
LOSS W
NINDSL90L 1048 478 340 380 440 395 N/F 858 B44
NINDSL120L 1236 478 340 380 440 395 N/F 1046 B47
NINDSL150L 1424 478 380 420 520 520 N/F 1234 B54
NINDSL180L 1 674 478 380 420 520 610 N/F 1484 B57
NINDSL210L 1987 478 380 420 520 710 1500 1797 C66
TECHNICAL SPECIFICATIONS
09 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

EHC NEPTUNE DIRECT
EHC NEPTUNE INDIRECT
25.0˚
40.0˚
45.0˚
35.0˚
15.0˚
50.0˚
10.0˚
15.0 0
25.0 0
30.0 0
45.0 0
160mm 195mm
FD
22mm HOT
DRAW - OFF
“ F PTRV BOSS
22mm SECONDARY
RETURN (not always fitted.
See table)
22mm COLD FEED WITH
DIP PIPE TO DEFLECTOR
IN BOTTOM OF CYLINDER
1
2
SECOND IMMERSION
HEATER
CODE HEIGHT DIAMETER D F ERP BAND Load Profile kWH/Annum
NDIR120L 906 550 N/F 510 D M 1461
NDIR150L 1093 550 N/F 610 D M 1492
NDIR180L 1281 550 N/F 710 D L 2783
NDIR210L 1469 550 1000 810 D L 2827
NDIR250L 1719 550 1250 950 D L 2871
NDIR300L 2032 550 1500 1100 DXL 4543
22mm COLD FEED WITH
DIP PIPE TO DEFLECTOR
IN BOTTOM OF CYLINDER
22mm SECONDARY
RETURN (not always tted.
See table)
22mm HOT
DRAW - OFF
“ F PTRV BOSS
1
2
DRY STAT
POCKET
SECOND IMMERSION HEATER
(not always tted. See table)
F E D C B A
CODE HEIGHT DIAMETER A B C D E F ERP BAND STANDING LOSS
NIND120L 906 550 290 330 390 345 N/F N/F B44
NIND150L 1093 550 330 370 465 385 N/F N/F B51
NIND180L 1281 550 330 370 465 385 N/F N/F B55
NIND210L 1469 550 365 405 465 465 N/F 1150 C66
NIND250L 1719 550 365 405 465 560 950 1400 C77
NIND300L 2032 550 365 405 465 660 1100 1600 C88
All Dimensions are in mm and
are of the cased unit.
N/F = not fitted.
TECHNICAL SPECIFICATIONS
10
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

TECHNICAL SPECIFICATIONS
EHC NEPTUNE SOLAR INDIRECT
All Dimensions are in mm and are of the cased
unit.
N/F = not fitted.
DRY STAT
POCKET
DRY STAT
POCKET
22mm COLD
FEED WITH DIP PIPE
TO DEFLECTOR IN
BOTTOM OF CYLINDER
22mm SECONDARY RETURN
(not always fitted. See table)
½” F PTRV BOSS
22mm HOT DRAW-OFF
EF D C B A G H
25.0 015.0 0
40.0 045.0 0
35.0 0
50.0 0
CODE HEIGHT DIAMETER A B C D E F G H ERP BAND STANDING LOSS (W)
NSIND180L 1281 550 290 345 674 729 N/F 1080 390 725 B55
NSIND210L 1469 550 365 420 779 834 1150 1268 465 830 C66
NSIND250L 1719 550 365 420 950 1005 1400 1518 465 1000 C77
NSIND300L 2032 550 365 420 979 1034 1600 1832 465 1030 C88
11 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

EHC NEPTUNE SOLAR INSTALLATION
12
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS
INDIRECT TWIN COIL CYLINDER
GENERAL
When installing this product it is essential the overall
installation meets all current legislation including, in
particular, the high limit isolation requirements of Building
Regulation G3. This document is designed to assist in
achieving that aim.
WATER
The potable water connection and tundish discharge
connection are to be connected in exactly the manner
described in Pages 5 to 6 of this manual.
UPPER COIL
The upper coil is connected to the fossil fuel boiler as per the
instructions for the EHC Neptune Indirect single coil model
with the dual stat control and high limit thermostat inserted
into pocket D (diagram page 11). The wiring requirements are
as depicted on page 12-13.
LOWER COIL: SOLAR INSTALLATION
The flow and return from the solar heat source are to
be connected to the indirect coil. Either primary coil
connection may be utilised as the flow or return. The solar
primary circuit must have its own dedicated circulating
pump, thermal and safety controls which must be installed
as per the solar manufacturers instructions. The solar
control system used must be of the solar differential control
type and should be connected to the solar sensor.
The solar sensor, supplied as part of the solar controls
should be inserts into Pocket B and is held in-situ with the
black sensor pocket retaining bung provided.
It is necessary to connect the solar pump via the over-
temperature high limit cut-out (provided) to ensure the heat
input to the solar coil is interrupted if the cylinder overheats.
Some method to prevent thermosyphoning must also be
employed. Non-return check valves in the primary flow and
return pipework would be acceptable. If solar controls do not
offer appropriate isolation a 2 port zone valve (not supplied)
can be used with the pump and high limit stat as shown to
the right.
NOTE: If it is intended to fit a cylinder with a solar coil to be
used at a later date, the 2 coils should be connected in series
to make use of the solar coil, using the dual stat in Pocket D.
The Domestic Heating Compliance Guide document L1A
and L1B provides excellent advice in sizing both cylinder
designated solar areas and heat exchangers to the surface
area of the solar collectors. Using this guide EHC are able to
offer sizing advice for specification.
NB: The total detail of compliance guide document should
be consulted prior to specifying product or commencing
design.
E C 1 2
HIGH LIMIT CONTROL
Mains supply
double pole
fused spur
230/220 3amp L
N
E
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
B
LG O
B
R
G
Y
ZONE VALVE
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
B
LG O
B
R
G
Y
ZONE VALVE
L
N
PUMP
E
3
2
E C 1 2
HIGH LIMIT CONTROL
Mains supply
double pole
fused spur
230/220 3amp L
N
E
The schematic wiring diagrams below depict an IMIT high limit
control stat and the connections are numbered accordingly.
Where an alternative is supplied connect as per manufacturer’s
instructions.
Mains supply
double pale
fused spur
230/220 3amp
Mains supply
double pale
fused spur
230/220 3amp

SCHEMATIC WIRING
13 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

COMMISSIONING
SERVICING
FLUSHING & FILLING
Check that the pressure in the expansion vessel is 3 bar
(45PSI), i.e. the same as the setting of the pressure reducing
valve. The valve is of the car tyre (Schrader) type. Check
all the connections for tightness including any factory
made connections such as the immersion heater and the
temperature and pressure relief valve. Before filling, open
the hot tap furthest away from the EHC Neptune to let air
out. Open the cold main isolation valve and allow the unit to
fill. When water flows from the tap allow it to run for a short
while to flush through any dirt, swarf or flux residue. Close
the tap and open every other hot tap in turn to purge all
remaining air.
DIRECT UNITS
After filling with water and after sterilisation liquid has
been purged, switch on the power to the immersion heaters
and allow the unit to start to heat. The immersion heater
is supplied preset at 55°C. Turning fully to + sets to approx
65°C. Allow unit to heat up, adjust the thermostat so that
the heater switches off at 60°C. Record information on
Commissioning Record (Page 19).
INDIRECT UNITS
Consult the boiler manufacturer’s commissioning
instructions and fill the primary circuit. Ensure the lever on
the two port valve is set to the filling position. When full,
move the lever back. Switch the programmer to Domestic
Hot Water (DHW) and allow the unit to start to heat. Adjust
the dial of the dual thermostat to between 55°C and 65°C
as required. Allow unit to heat up, adjust the thermostat so
that the heater switches off at 60°C. Record information on
Commissioning Record (Page 19).
STORAGE TEMPERATURE
The recommended storage temperature for both direct
and indirect cylinders is 60-65°C. In hard water areas
consideration should be given to reducing this to 50-55°C.
In many healthcare applications the guidance on Legionella
control and safe water delivery temperatures will require
storing the water at 60-65°C, distributing at 50- 55°C
and using thermostatic mixing valves to control the final
temperature. For details consult the NHS Estates Guidance
on safe hot water temperatures.
SAFETY VALVE CHECKS
During heat-up there should have been no sign of water
coming from either the expansion relief valve or the
temperature/pressure relief valve. Now hold both of these
safety valves fully open, allowing as much water as possible
to flow through the tundish. Check that your discharge
pipework is free from debris and is carrying the water away
to waste efficiently. Release the valves and check that they
reseat properly. On Completion of commissioning, fill in the
Commissioning Record and leave with the house owner.
GENERAL
Servicing should only be carried out by competent installers
and any spare parts used must be purchased from the Electric
Heating Company. NEVER bypass any safety devices or
operate the unit without them being fully operational.
DRAINING
Isolate from the electrical supply to prevent the immersion
heaters burning out. Turn off the boiler. Isolate the unit from
the cold mains. Attach a hose to the draining tap ensuring that
it reaches to a level below the unit (this will ensure an efficient
syphon is set up and the maximum amount of water is drained
from the unit). First open the hot tap closest to the unit and
then open the draining tap.
WARNING: WATER DRAINED OFF MAY BE VERY HOT!
IMPORTANT: After draining the cylinder do not close the hot
tap until the cylinder has fully cooled, failure to follow this
instruction may result in damage to the cylinder and will
invalidate the guarantee.
ANNUAL MAINTENANCE
The EHC Neptune requires an annual service in order to
ensure safe working and optimum performance. It is essential
that the following checks are performed by a competent
installer on an annual basis. Commonly this is done at the
same time as the annual boiler service.
1) Twist the cap of the expansion relief valve on the inlet
control set and allow water to flow for 5 seconds. Release
and make sure it resets correctly. Repeat with the pressure/
/ temperature relief valve. In both cases check that the
discharge pipework is carrying the water away adequately. If
not, check for blockages etc. and clear.
WARNING: THE WATER DISCHARGED MAY BE VERY HOT!
2) Check that any immersion heaters fitted are working
correctly and that they are controlling the water at a
temperature between 55°C and 65°C.
3) Check the pressure in the expansion vessel is charged to 3
bar. Turn off the water supply to the unit and open a hot tap
first. The air valve on expansion vessel is a Schrader (car tyre
) type. Air or CO2may be used to charge the expansion vessel.
4) Unscrew the head on the inlet control set and clean the
mesh filter within.
5) The service history supplied with this unit should be
updated at each service.
YOUR GUARANTEE MAY BE VOID WITHOUT PROOF OF
ANNUAL SERVICING.
14
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

FAULT FINDING
SPARE PARTS
A full range of spare parts is available from Electric Heating
Company. Tel: [phone] see page 2 for part numbers.
USER INSTRUCTIONS
Your system is automatic in normal use and requires only
annual servicing. You should employ a competent installer
to perform the annual servicing. Normally this is timed to
coincide with the annual boiler service.
IF WATER IS FLOWING FROM THE SAFETY VALVES
THROUGH THE TUNDISH THIS INDICATES A FAULT
CONDITION AND ACTION IS NEEDED.
If this water is hot, turn the boiler and / or the immersion
heater off. Do not turn off the water until the discharge runs
cool. The discharge may also stop.
CALL OUT A COMPETENT PLUMBER TO SERVICE THE
UNIT.
Tell them you have a fault on an unvented cylinder. We stock
all the spare parts they may need (see page 2).
DRAINING
IMPORTANT: After draining the cylinder do not close the
hot tap until the cylinder has fully cooled; failure to follow
this instruction may result in damage to the cylinder and
will invalidate the guarantee.
FAULT POSSIBLE CAUSE SOLUTION
Water escaping from the case Compression fitting on hot - draw off not sealing Check/remake joint with sealing paste
Cold water at hot taps Direct - immersion heater not switched on or cutout has
triggered
Check / reset
Indirect - boiler not working Check boiler - consult boiler manufacturers' instructions
Indirect - motorised valve fault Check plumbing / wiring to motorised valve
Indirect - cutout in dual stat has operated Reset and investigate cause
Water discharges from expansion
relief valve
If continual - pressure reducing valve ( part of inlet control set)
may not be operating correctly
Check outlet pressure from inlet control set is 3 bar.
If continual - expansion relief valve seat may be damaged Remove cartridge - check seat and renew if necessary
If intermittent - expansion vessel charge may have reduced /
bladder perished
Check pressure in expansion vessel. Recharge to 3 bar if
necessary. If bladder perished replace vessel.
Unit is being back pressurised With cylinder cold check pressure in cylinder. If this is the same
as the incoming mains pressure then you are getting backfeed.
Install a balanced cold supply (see page 5)
Water discharges from temperature
& pressure relief valve
Unit has overheated - thermal controls have failed Switch off power to boiler and immersion heaters.
Leave water supply on. Wait until discharge stops.
Isolate water supply and replace if faulty
Milky / cloudy water Oxygenated water Water from any pressurised system will release oxygen bubbles
when flowing. The bubbles will settle out.
No hot water flow Cold main off Check and open stopcock
Strainer blocked in pressure reducing valve Isolate water supply and clean
Inlet control set may be fitted incorrectly Check and refit as required
Noise during hot water draw-off
-typically worse in the morning
Loose airing cupboard pipework Install extra clips
Hot or warm water from cold tap If tap runs cold after a minute or so the pipe is picking up heat
from heating pipework.
Insulate / re-route
15 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

SPECIFICATION
CYLINDER DETAILS & PERFORMANCE
PRODUCT CODE WEIGHT EMPTY WEIGHT FULL CAPACITY DEDICATED SOLAR VOLUME FOSSIL FUEL VOLUME HEAT-UP TIME 70% RE-HEAT TIME INDIRECT COIL SURFACE AREA INDIRECT COIL CAPACITY INDIRECT COIL kW RATING SOLAR COIL SURFACE AREA SOLAR COIL CAPACITY HEAT LOSS (kW/24Hr)
EHC NEPTUNE DIRECT SLIMLINE
NDIRSL90L 29 120 90 - - 80m -N/A N/A N/A N/A N/A 1.05
NDIRSL120L 38 160 120 - - 105m -N/A N/A N/A N/A N/A 1.12
NDIRSL150L 46 200 150 - - 125m -N/A N/A N/A N/A N/A 1.29
NDIRSL180L 54 235 180 - - 140m -N/A N/A N/A N/A N/A 1.37
NDRIRSL210L 60 270 210 - - 160m -N/A N/A N/A N/A N/A 1.64
EHC NEPTUNE INDIRECT SLIMLINE
NINDSL90L 36 130 90 -17m 22s 15m 12s 0.67 3.69 16.1 N/A N/A 1.05
NINDSL120L 44 165 120 - 25m 01s 16m 25s 0.67 3.69 19.0 N/A N/A 1.12
NINDSL150L 52 205 150 - 26m 24s 19m 37s 0.77 4.26 19.5 N/A N/A 1.29
NINDSL180L 60 240 180 -32m 14s 23m 05s 0.77 4.26 20.4 N/A N/A 1.37
NINDSL210L 68 280 210 -36m 36s 27m 40s 0.77 4.26 23.4 N/A N/A 1.64
EHC NEPTUNE DIRECT
NDIR120L 30 150 120 - - 110m -N/A N/A N/A N/A N/A 1.05
NDIR150L 35 185 150 - - 135m -N/A N/A N/A N/A N/A 1.23
NDIR180L 40 220 180 - - 160m -N/A N/A N/A N/A N/A 1.32
NDIR210L 45 255 210 - - 185m -N/A N/A N/A N/A N/A 1.58
NDIR250L 50 300 250 - - 225m -N/A N/A N/A N/A N/A 1.84
NDIR300L 55 355 300 - - 270m -N/A N/A N/A N/A N/A 2.10
EHC NEPTUNE INDIRECT
NIND120L 35 155 120 -23m 47s 18m 00s 0.67 3.69 18.35 N/A N/A 1.05
NIND150L 40 190 150 - 29m 36s 20m 35s 0.77 4.26 19.07 N/A N/A 1.23
NIND180L 45 225 180 - 31m 58s 22m 47s 0.77 4.26 20.28 N/A N/A 1.32
NIND210L 50 260 210 - 33m 05s 26m 16s 0.86 4.83 23.08 N/A N/A 1.58
NIND250L 55 305 250 - 41m 18s 28m 20s 0.86 4.83 24.40 N/A N/A 1.84
NIND300L 60 360 300 - 46m 01s 32m 52s 0.86 4.83 24.87 N/A N/A 2.10
EHC NEPTUNE SOLAR INDIRECT
NSIND180L 50 235 180 125 55 25m 15s 17m 02s 0.67 3.69 20.2 0.67 3.69 1.32
NSIND210L 55 270 210 145 65 28m 31s 15m 50s 0.77 4.26 23.4 0.86 4.83 1.58
NSIND250L 60 315 250 160 90 31m 42s 22m 42s 0.77 4.26 28.3 0.86 4.83 1.84
NSIND300L 65 370 300 200 100 36m 04s 21m 30s 0.86 4.83 29.2 0.86 4.83 2.10
16
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

TECHNICAL SPECIFICATIONS
Element Rating 3kW 240 V
Thread Type 1 3/4” BSP
Fuse Requirement 13A via Double Pole Switch
Control Thermostat for Element - Temperature Range 45oC - 65oC
High Limit Thermostat for Element - Temperature Set Point 85oC
Maximum Inlet Water Pressure 12 Bar
Operating Pressure 3.0 Bar
Expansion Valve Opening Pressure 6.0 Bar
Expansion Vessel Charge Pressure 3.0 Bar
Maximum Operating Pressure 7.0 Bar
Opening Pressure of T & P Valve 7.0 Bar
Opening Temperature of T & P Valve 90oC
Maximum Pressure on Primary Circuit (Indirect & Solar Coil) 3.5 Bar
PRESSURE SPECIFICATIONS
IMMERSION ELEMENT SPECIFICATIONS
17 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

Commissioning Date....................................................................
Customer Name............................................................................
Customer Phone Number ...........................................................
Cylinder Model Number ................................................................
Cylinder Serial Number ..............................................................
Engineer’s Name............................................................................
Company Name.............................................................................
Company Address .......................................................................
Telephone Number.......................................................................
Registered Operator ID Number,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Building Regulation Notification Number (if applicable)
.......................................................................................................
COMMISSIONING RECORD
PRIMARY INDIRECT SYSTEM INFORMATION
Primary circuit SEALED OPEN VENTED
Primary circuit flow temperature ............................................
Primary circuit expansion vessel size required .....................
Primary circuit expansion vessel pre-charge ........................
Primary flow temperature .......................................................
POTABLE WATER INFORMATION
What is the standing pressure at the cylinder? ....................
What is the dynamic pressure at the cylinder? ....................
What is the pre-charge in the potable vessel? ......................
Where is the Pressure Reducing Valve fitted?
.....................................................................................................
What is the PRV setting?..........................................................
Has the Expansion Relief Valve been tested? ......................
Has the T & P valve been tested? ...........................................
Does the discharge pipework meet building regulations?
..................................................................................................
Does the discharge pipework carry discharge away in a safe
manor? ....................................................................................
Have all safety features been checked? ............................
DOES THE INSTALLATION COMPLY WITH THE APPROPRIATE BUILDING REGULATIONS? YES NO
HAS THE SYSTEM BEEN COMMISSIONED IN LINE WITH INSTRUCTIONS? YES NO
HAS THE PRIMARY CIRCUIT BEEN DOSED WITH INHIBITOR? N/A YES NO
HAVE THE CORRECT CONTROLS BEEN INSTALLED? YES NO
HAS THE SYSTEM BEEN FULLY EXPLAINED TO THE CUSTOMER? YES NO
COMMISSIONING ENGINEER SIGNATURE.........................................................................................................................................
CUSTOMER SIGNATURE ..........................................................................................................DATE .................................................
18
EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS

SERVICE 1 Date..................................................................
Engineer’s Name............................................................................
Company Name.............................................................................
Telephone Number.......................................................................
Pressure in Potable Expansion Vessel......................................
Safety valves functioning YES NO
Actions ........................................................................................
Discharge pipe clear YES NO
Actions..........................................................................................
Temperature of hot water............................................................
Immersion heater connected YES NO N/A
Actions ........................................................................................
Signature......................................................................................
SERVICE 2 Date..................................................................
Engineer’s Name............................................................................
Company Name.............................................................................
Telephone Number.......................................................................
Pressure in Potable Expansion Vessel......................................
Safety valves functioning YES NO
Actions ........................................................................................
Discharge pipe clear YES NO
Actions..........................................................................................
Temperature of hot water............................................................
Immersion heater connected YES NO N/A
Actions ........................................................................................
Signature......................................................................................
SERVICE 3 Date..................................................................
Engineer’s Name............................................................................
Company Name.............................................................................
Telephone Number.......................................................................
Pressure in Potable Expansion Vessel......................................
Safety valves functioning YES NO
Actions ........................................................................................
Discharge pipe clear YES NO
Actions..........................................................................................
Temperature of hot water............................................................
Immersion heater connected YES NO N/A
Actions ........................................................................................
Signature......................................................................................
SERVICE 4 Date..................................................................
Engineer’s Name............................................................................
Company Name.............................................................................
Telephone Number.......................................................................
Pressure in Potable Expansion Vessel......................................
Safety valves functioning YES NO
Actions ........................................................................................
Discharge pipe clear YES NO
Actions..........................................................................................
Temperature of hot water............................................................
Immersion heater connected YES NO N/A
Actions ........................................................................................
Signature......................................................................................
SERVICE HISTORY
19 EHC NEPTUNE
UNVENTED HOT WATER CYLINDERS