elco Tudor NHREC Manual

Gas Condensing
Storage Water Heater
Model : Tudor NHREC
Installation & Operating
instructions
Code : L374 01-2021

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Thank you for choosing our condensing hot water heater to ensure your
domestic hot water production.
Please retain the device’s operating instructions in a
safe place for future reference.
PRODUCT CONFORMING TO EU DIRECTIVE 2012/19/EU
The crossed-out wheeled bin symbol on the appliance indicates that
the end-of-life product, to be treated separately from domestic waste,
must be returned to a waste sorting center for electrical and electronic
equipment or returned to the dealer, on the day of purchase of a new
equivalent device.
The user must ensure that the device at the end of its life is disposed of in
an appropriate collection center.
Selective sorting, which allows the recycling of the appliance at the end of
its life cycle, the treatment of it and the environmentally friendly disposal,
helps to avoid possible negative effects on the environment, health and
recycling of the materials that make up the product.
For more information on existing waste collection centers, contact the
local waste collection service or the store where you purchased your
appliance.

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1. RECOMMENDATIONS
a. General Recommendations
1. This manual forms an integral part of the appliance. It is to be kept safe and
accessible for consultation if necessary and must accompany the appliance in case
of transfer to another owner or user and / or transfer to another installation.
2. Carefully read the instructions and understand the advice provided. This will ensure the
safe installation, use and maintenance of the appliance.
Failure to do so may invalidate the warranty.
3. This appliance must only be used for its intended purpose. The manufacturer can
under no circumstances be held liable for damages resulting from improper,
incorrect or unreasonable use or from non-observance of the instructions contained
in this manual.
4. Installation, maintenance and other work must be carried out by a competent
person in accordance with the relevant regulations and the manufacturer's
instructions.
5. This appliance is designed to produce hot water for domestic use. It should be
connected to the distribution mains supply for domestic hot water in accordance with
the performance levels and power-rating of the appliance.
6. The manufacturer shall not be liable for damage to persons, animals or property
caused by improper installation.
7. Ensure that all packing materials are safely disposed of (staples, plastic bags,
expanded polystyrene, etc.), as they represent a sources of danger, especially for
children.
8. Do not touch the appliance if you have bare feet or with wet parts of the body.
9. In the event of faults and/or malfunctions, switch the appliance off and shut off the
gas valve. Do not attempt to perform any repairs yourself but contact an
authorised service technician.
10. For repairs, contact an authorised service technician and specify the use of only
original spare parts where possible. Failure to comply with the above may
compromise safety and disclaim all liability of the manufacturer.
11. The hot water temperature is controlled by thermostat which also serves as a safety
device (requiring manual reset) to prevent dangerous water temperatures. To avoid
any risk of scalding, do not exceed a maximum temperature of 50 °C at the tap
discharge via suitable mixers. To avoid the risk of legionella issues, the control
thermostat must be set to at least 60 °C.
12. Ensure that the electrical connection is as indicated in the relevant section-10
13. No flammable objects should be stored in the vicinity of the appliance.
14. If the appliance is out of service for more than one month, close the hydraulic
circuits connected to the water heater and drain the appliance. If the appliance is
left unused in winter for a long period in an unheated space, it is advisable to
drain it completely to avoid any risk of freezing. The manufacturer shall not be liable
for damage caused by freezing or leaking water from the installation.
15. The appliance must not be installed in damp areas (RH ≤ 80%) and must be protected
against splashing water to avoid damage to electrical and thermal components.

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16. Do not store any type of object against the appliance.
17. For reliable and safe performance and warranty recognition, carefully follow the
information in this manual and use only the spare parts and flue kits supplied by the
Manufacturer.
18. This appliance should not be operated by children and they must be attended at all
times.
b. Installer Recommendations
The appliance and its safety valve (supplied separately) must be installed in a frost-
free and properly ventilated room.
It is essential that the discharge of the safety valve is connected to a tundish,
suitably connected to a drain. Specific attention to system integrity should be made
if the water heater is installed above inhabited premises (e.g.- elderly persons care
home)
To allow maintenance operations, it is imperative to provide appropriate clearances
as detailed in figure - 5.
2. REGULATIONS
Gas or liquefied petroleum equipment installations must be carried out in
accordance with regulations.
This appliance may operate with a non-sealed or sealed combustion circuit of the
types B23, B23P, B33, C13, C33, C53 & C93
Categories: II2H3P G20-20mbar - G31-37mbar
NATURE OF
GAS
COMMON DESIGNATION NATURAL GAS PROPANE
REFERENCE GROUP H - G20
34.02MJ/m3
G31
46.34 MJ/m3
Net calorific value (15° / 1013 mbar)
NORMAL SUPPLY PRESSURE 20 37
a. European Directives and Standards
Directive 90/396/CEE as amended by 2009/142/CE - Gas Appliances;
Directives 2009/125/EC (ErP) & 2010/30EU (Energy Labelling)
Directive DESP 97/23/CE - Pressure equipment;
BS EN 89 (2000) « Devices for the production of hot water by storage for sanitary uses
using gaseous fuels »;
+ BS EN 89/ A3 (2006)
+ BS EN 89/ A4 (2007)
BS EN 298 (2003) - Automatic control and safety systems for burners and apparatus with or
without a fan using gaseous fuels ;
BS EN 437+A1 (2009) Test gas – Test pressure – Category of equipment;

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CEN/TR 1749 (2013) European scheme for the classification of gas appliances according to
the method of evacuation of the combustion products (types)
b. Installation Requirements
It is the Law that all gas appliances are installed by competent persons (Gas Safe
Registered), in accordance with the Gas Safety (Installation and Use)
Regulations 1998 (as amended). Health & Safety requirements must be taken into
account when installing any equipment. Failure to comply with the above may lead to
prosecution. It is in your own interest and that of safety, to ensure the Law is complied
with.
The installation of the appliance MUST be carried out by competent personnel and
comply with the I.E.E. Wiring Regulations, National & Local Building Regulations,
Water Bye-laws, Bye-Laws of the Local Water Undertaking, Fire Authority
Requirements any relevant requirements of the Local Authority, and Health and
Safety Executive.
Statutory Instruments
Water Supply (Water Quality England & Wales) Regulations 2016 - as amended
The Public Water Supplies (Scotland) Regulations 2014 - as amended
The Water Supply (Water Fittings) Regulation (Northern Ireland) 2009 - as amended
For gas fired equipment the installer should also refer to relevant IGEM
Publications:
IGE/UP/1 Soundness testing and purging of industrial and commercial gas
installations.
IGE/UP/1A Soundness testing and direct purging of small low pressure industrial and
commercial natural gas installations.
IGE/UP/2 Gas installation pipe work, boosters and compressors on industrial and
commercial premises.
IGE/UP/10 Installation of gas appliances in industrial and commercial premises.
Detailed recommendations are contained in the following British Standard Codes of
Practice:
BS 5440 Flueing and ventilation for gas appliances of rated input not exceeding
70kW net
BS 6644 Specification for the installation and maintenance of gas-fired hot water
boilers of rated inputs between 70 kW (net) and 1.8 MW (net).
BS 6880 Part 1, 2 & 3 Code of Practice for low temperature hot water heating
systems of output greater than 45kW.
BS 7074 Part 1: Application, selection and installation of expansion vessels and
ancillary equipment for sealed water systems.
Part 2: Code of Practice for low and medium temperature hot water heating systems.
BS 7671 Requirements for electrical installations. IET Wiring Regulations. 17th
edition.
BS 8550 Guide for the auditing of water quality sampling

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BS 8558 Guide to the design, installation, and maintenance of services supplying
water for domestic use within buildings. Note: this document is complimentary to BS
EN 806
BS 14743 Water conditioning equipment inside buildings. Softeners. Requirements
for performance, safety and testing
BS EN ISO 4126-1 Safety devices for protection against excessive pressure. Safety
valves.
BS EN 806 Specification for installations inside buildings conveying water for human
consumption
Note: - BS6700 - The Design, Installation, Testing and Maintenance of Services
supplying water for domestic use within buildings; is still referred to. However this
document has been superseded by BS EN 806
BS EN 1717 Protection against pollution of potable water in water installations and
general requirements of devices to prevent pollution by back-flow
Electrical Standards:- BS 3456 Part 201, EN 60335 Part 1
CP 342-2 Code of practice for centralised hot water supply. Buildings other than
individual dwellings.
The Health and Safety Commission (HSC) approved code of practice and
guidance document L8 - HSG274: Legionnaires disease. Technical Guidance.
Note: - due to the scope of this document, all non-domestic premises must
implement some form of water treatment.
CIBSE Publications
CIBSE Guide G Public Health Engineering
CIBSE TM13: Minimising the risk of Legionnaires’ disease.
CIBSE Guide H Building Control Systems.
CIBSE Guide Energy Efficiency in Buildings.
CIBSE Commissioning Code B: 2002.
Department of Health
Health Technical Memorandum (HTM) 04-01: The control of Legionella, hygiene,
‘safe’ hot water, cold water and drinking water systems.
Part A Design, installation and testing.
Part B Operational Management Department of Health (DH). Addendum
Pseudonomas aeruginosa - advice for augmented care units.
HTM 04-04 The Control of Legionella in Health Care Premises- Code of Practice:
2006
General Requirements
All connections to the local water main shall comply with Water Supply (Water
Fittings) Regulations 1999 (as amended). Compliance with the Regulations can be
demonstrated by certification from notified body organisations such as WRAS or
KIWA.
Unvented Systems
Building Regulations - use of unvented hot water storage systems with volumes
exceeding 15 litres. G3 (England & Wales), P3 (Scotland) & P2 (Northern Ireland)
The unvented system components allows the storage vessel to be fed directly from
the mains cold water supply, or from a booster pump set, without the need for feed

Page 7
and expansion tanks. The unvented system components should be approved and comply
with the Water Supply (Water Fittings) Regulations 1999 (as amended), including a suitably
sized temperature or temperature and pressure (T&P) relief valve, which locates directly
into the top portion of the storage vessel
3. WARNINGS
Notice regarding the development and publication of this manual:
➢ It contains the most recent descriptions and characteristics of the product.
➢ The contents of this manuals are subject to change without notice :
We reserve the right to make changes, without notice, to the features and elements contained
herein. We may not be held liable for any prejudice (including consequential damages)
caused by reliance on the material presented, including, but not limited to, typographical
errors and other publication errors.
4. CONDITIONS FOR APPLICATION OF THE
MANUFACTURER’S WARRANTY
Standard and current terms of warranty are detailed on our web site www.elco.co.uk
5. GENERAL INFORMATION
DHW condensing hot water heater - with a very simple and flexible operation, you
can always dispose of hot water at the desired temperature and the desired flow
(within the limits of the capacity of the appliance) while respecting the (regulatory)
thermal and environmental issues.
a. ERP CLASSIFICATION

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b. Characteristics
Figure 1a - general layout Plan view
Legend:
1. Gas Inlet
2. Combustion System
3. Ignition Electrode
4. Ionisation Electrode
5. Combustion Chamber
6. Concentric flue
7. Air Inlet
8. Flue Outlet
9. Cold Water Inlet Pipe (1”M)
10. Hot Water Outlet Pipe (1”M)
11. Control & Limit Probes (T°C)
12. Anodes (3/4’’F)
13. Insulation
14. Heat Exchanger Flue/Water
15. Enameled Steel Tank
16. Controller
17. Control Box
18. Lower Cylinder Removable
Case
19. Condensates Discharge (1/2’’M)
20. Drain (1’’ F)
21. Flue gas sampling point
22. Secondary return connection (1”F)
Figure 1b - SECTIONAL VIEW

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General technical characteristics - see. Figures -1a & 1b:
➢ Enameled tank (Sanitary conformity according to standard BS EN 89 &
WRAS) allowing operation with a maximum temperature of 95°C ;
➢ Rigid insulation in pre-lacquered steel A2 fire class ;
➢ Stainless steel concentric duct circuit (sealed) suitable for types C13, C33, C53
& C93;
➢ Stainless steel duct circuit (sealed) suitable for types B23, B23P & B33;
➢ Gas type G20/G31 ;
➢ Factory calibrated by model ;
➢ Premix Air / Gas burner ;
➢ Electronic control with back-lit display
➢ Integral Protech electronic anode protection system;
➢ Device certified to the European standard for gas storage water heaters, for
Sanitary use (BS EN 89).
It is imperative to read this documentation before commissioning. At your
request, our Post sale department can organise a commissioning visit
(optional).
6. TECHNICAL CHARACTERISTICS
a. CE marking
We hereby certify that the DHW gas fired condensing storage water heaters are in
conformity with the requirements of Directive: EU 2016/426
b. Type
Depending upon the type of equipment selected and site conditions, STANDARD
connections for the air supply and flue gas discharge C13, C33, C53 & C93 and B23, B23P & B33
according to CEN/TR1749 are proposed (refer to section 9)

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:
:
c. Technical Data
:
* Gas Consumption @ 1013.25 mbar, 15°C
Technical Specifications Unit NHREC
20
NHREC
40
NHREC
65
DHW Capacity: Liters 213 269 350
Heat input: kW 20.2 40.5 63.7
Heat output: kW 18.55 37.51 61.2
Efficiency (Gross): % 91.6 92.5 96.0
DHW Capacity Recovery Time (△T = 50 °C): min 41 31 20
Hot Water Production (△T = 50 °C): l/h 319 645 1052
l/min 5.3 10.7 17.5
Hot Water Production (△T = 55 °C): l/h 290 586 957
l/min 4.8 9.8 15.9
Gas Consumption (G20-20 mbar)*: m3/h 1.9 3.72 6,2
Gas Consumption (G31 – 37 mbar)*: kg/h 1.5 2.8 4.6
Flue Gas Temperature (maximum) °C 52 53 60
Flue Gas Flow rate g/s 8.5 17 28
Total Power Consumption 230 V ~ 50 Hz (IP 20): W 100 120 235
Minimum / Maximum Working Pressure: Bar 1 - 7
Maximum Working Temperature: °C 80
Dimensions (L x l x H):
mm
1146 x
796 x
1415
1146 x
796 x
1730
1146 x
796 x
1989
Dimensions in wooden box (L x l x H):
mm
1182 x
888 x
1446
1182 x
888 x
1761
1182 x
888 x
2018
Empty Weight: Kg 169 244 280

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d. Minimum dimensions and clearances
The figures 2 give the dimensions of the
appliance and the minimum clearance to be
observed for maintenance or dismantling:
Figure 5 - Minimum clearances
Figure 2a - dimensions
FRONT VIEW
Figure 2b - dimensions
TOP VIEW
500mm above
NHREC 20 40 65
A 1396 1711 1968
B 923 1133 1304

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e. Packaging / Storage / Transport / Unpacking
Each unit, after factory checks and tests, is packaged in a wooden box and stored in a
warehouse with optimum conditions for delivery.
This appliance must be stored in a covered, frost-free room with high and low ventilation.
When it is transported, it must be fixed vertically and strongly in its original packaging
until the place of installation.
In order to unpack the device for its installation on the site, here is the procedure to
follow:
Dismantling the wooden
box:
- Uncouple the cap : 1
- Remove the posts : 2 et 3
- Remove the 4 screws : 4
- Remove the posts : 5 et 6
In case of height problem, it is possible to remove both ‘U’ section bases
- Remove the console and the lower trim panels (see p39)
- Unscrew both U sections attached to the feet of the tank
- Remove the U section (CAUTION when tilting the tank)
Warning!
After unpacking the unit, make sure that it is
completely intact.
Packaging elements must be sorted and collected
according to their nature for environmental
protection.

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7. HYDRAULIC CONNECTION & GAS
a. Hydraulic Connection
Refer to figures below to visualise the schematics of some of the main features to link the
hydraulic connections. The correct installation of the tank is the responsibility of the
installer.
Ensure that each unit and the associated pipe work are suitably earthed.
Figure 7.1 - NHREC Open vented system
Figure 7.2 - NHREC Unvented system - optional cold water boosted supply

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Figure 7.3 - Two NHREC in parallel unvented
Figure 7.4 - NHREC with buffer vessel unvented

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Legend :
1. Cold water mains supply
2. Isolating valve
3. Strainer
4. Pressure reducing valve
5. Expansion vessel
6. Non return valve
7. Pressure relief valve
8. Drain valve
9. NHREC water heater
10. Re-circulating pump
11. Hot water outlets
12. Temperature & Pressure
relief valve
13. De-Stratification pump
14. Buffer vessel loading pump
15. Hot water buffer vessel
16. Pressure relief valve
Figures -7.1 - 7.4 represents the general idea on how to install and link appliances (in
parallel) in order to double the capacity of production. Also the schematic for an appliance
with a buffer vessel allowing an increased capacity of production and ensuring a better
quality of service and the availability of the DHW.
b. Tips & Recommendations
☞ The Gas entry is via the 3/4” connection on the bottom left of the tank:
➢ Ensure that a filter and isolating valve are accessible close to the appliance.
➢ The gas supply needs to have a union and valve close to the appliance.
➢ The gas supply must be in accordance with BS6644 and purged in accordance
with IGE/UP1
NOTE: The burner is preset to the correct flow. All tanks are factory set
VERIFY THE NATURE OF DISTRIBUTED GAS BEFORE ADAPTATION OF THE
APPLIANCE
☞ The cold water inlet situated on top of the tank is a 1’’ connection
Open vented systems - refer BS EN 806 & BS 6700
➢ Ensure that the feed and expansion tank is sized to provide sufficient cold water
storage and accommodate system expansion without the risk of overflowing.
➢ Ensure that the static headed created by the feed and expansion tank does not
exceed the maximum working pressure and that it provides sufficient head
pressure so that flow can be maintained at all outlets likely to be operating
concurrently. Minimum cold feed pipe size 1” (28mm)
➢ Ensure that the open vent pipe is adequately sized (minimum 11/4” - 32mm)
connecting the domestic hot water flow to the feed and expansion tank

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➢ The fitting of a 3/4” (20mm) safety pressure relief valve to the tank flow is
recommended. No isolating valves should be fitted between the water heater and
the connection points for the open vent and relief valve
Unvented systems - refer BS EN 806 & BS 6700
➢ Install a stop valve on the cold water supply. The installation of the filter is
strongly recommended in order to eliminate any solid particulates or debris.
➢ Ensure that the setting of the pressure reducing valve does not exceed the
maximum working pressure of the water heater.
➢ Install a cold water inlet valve group (option supplied by Elco) incorporating non
return valve, pressure relief valve and pressure reducing valve
➢ Install a suitably sized expansion vessel acknowledging the system volume
(option supplied by Elco) in accordance with BS EN 7074
➢ The fitting of the T&P valve must be in accordance with Building Regulation G3.
(option supplied by Elco)
☞ The hot water outlet situated on top of the tank is a 1’’ connection
Add an automatic air vent (AAV) on the hot water outlet and as close as
possible to the tank.
Do not increase the diameter of the hot water outlet pipe, as larger diameter
pipes increases heat losses.
It is strongly recommended that a thermostatic mixer/valve is installed
between the water heater and point of use to avoid any risk of scalding.
The appliance drain pipe should incorporate a 1’’ valve. The drain water needs
to be visible either through a tundish or directly to drain.
Refer to BS 8558 for guidance on system design and materials. Pipe work
connected to the appliance should be easily assembled and disassembled.
Ensure that all pipe work is suitably earthed, as close as possible to the
appliance.
Check that the inlet water pressure does not exceed 5 bar. For pressure above
this limit, install a pressure reducing valve.
The condensate discharge must comply with the Building Regulations and
Water Bye-laws. Appliance discharge must not be blocked or modified.
c. Principle of Operation (see Figure -1)
The appliance is equipped with a premix burner. The Gas/air mix passes though the
fan via the venturi. The gas valve ensures the gas flow in the venturi. The venturi
guarantees the optimal gas/air mix with the air flow monitored by the fan speed.
Combusted gases pass from the burner into the combustion chamber and through
the heat exchanger immersed in the stored water. The flue gases pass through the
spiral heat exchanger transferring heat until the dew point is reached, resulting in
condensation and the additional transfer of latent heat of condensation.
During condensation, latent heat is transferred to the water. Thus increasing the
efficiency performance. The condensate is discharged through the siphon.

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The control sensor monitors the DHW temperature in the tank. As the
temperature drops below the set-point value, the controller starts the ignition cycle
and the burner starts. Once the flame is proved, the fan modulates to full power
and the DHW temperature is raised. The temperature is continually monitored and
the fan speed is reduced as the DHW reaches the set-point temperature. When the
DHW temperature is at set-point value, the burner switches off.
8.
QUALITY OF WATER
The system is intended for the storage and the production of hot water (DHW).
Under no circumstances should this equipment be fired before the cold water
supply to the equipment has been confirmed as suitable. All installations of hot
and cold water supplies shall be thoroughly flushed and cleaned before being filled
and used. If an installation is not flushed and/or if the water is not of the correct
quality, it may invalidate the manufacturer’s warranty.
Refer to ICOM document Water Quality Consideration of Domestic Hot Water
Systems for Commercial Applications.
The water must comply with the regulations for drinking water for human consumption.
Note - If the water specifications differ from the specifications in the table, the tank
protection cannot be guaranteed.
9.
FLUE SYSTEMS & VENTILATION
a. Flue systems C13, C33 – Concentric Room Sealed
The combustion air supply and flue gas discharge are contained in a concentric duct
arrangement: the external duct conveys the combustion air from outside the building
to the appliance combustion system. The inner duct conveys the products of
combustion from the heat exchanger to outside the building. This appliance can also
be configured with 2 separate ducts (air supply and flue gas discharge). This can allow
greater distances between the appliance and the outside terminals. The concentric flue
components supplied with the appliance include seals and clamps to ensure system
integrity as the flue duct is pressurised.
The appliance connector (fig 9.2) and straight lengths are supplied with the Tudor
Water Heater. The point of termination needs to be in compliance with current
Regulations and within the limitations of the appliance combustion system. The flue
system must have a slope of at least 3° to assist the evacuation of the condensates.
The total length of the concentric flue installations should not exceed 25 meters. Any
elbow has an equivalent resistance to a one metre length.

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BS5440 – Fig
(fig 9.2)
Combustion Air Supply
Products of combustion
IMPORTANT Flue terminal locations must be in accordance with BS5440 Flueing and
Ventilation of Gas Appliances of Rated Input not exceeding 70kW Net. For multiple
appliance installations, reference should be made to technical documents BS6644 and
IGE/UP/10.
BS5440 – Table C2 Room Sealed Chimney Outlet Positions

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Room Sealed Flue System with Separate Pipe for Combustion Air and Products of
Combustion. Type C53
For specific guidance please contact Elco Heating Solutions.
Diameters & Lengths of pipes - 1 elbow = 1 m ESL (Equivalent straight length)
20 / 40 / 65
Ø mm min (m) Max (m)
C 13 Horizontal 100 / 150 1 25
C 33 Vertical 100 / 150 1 25
C 53 Air 100 1 25
Flue Gas 100 1 25
Components Supplied Fitted to the Tudor Water Heaters
➢ An adaptor with measuring plug
(see opposite) ;
➢ One straight pipe 100/150 Lg.
according to power
➢ One adjustable element ;
➢ One support Bracket.
Figure 9.2 - appliance adaptor (adaptor)

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Depending on the flue type
Figure 9.3 - Flue installation B23/B23P
Elements available for configuration
Chimney type B23 & B23P:
Mandatory
100Ø Adaptor Mesh B23P
+
100Ø Vertical Terminal
or
100Ø Horizontal Terminal
Depending on installation
100Ø 1000mm Length
100Ø 450mm Length
100Ø 250mm Length
100Ø Adj Length 300-500mm
100Ø Adj Length 500-800mm
100Ø 30° Bend
100Ø 45° Bend
100Ø 90° Bend
100Ø Support Brkt
100Ø Inverted Cap
100Ø Support Collar
Figure 9.4 - Flue installation C13
Elements available for configuration
Chimney type C13:
Mandatory
100/150Ø 90° Bend
+
100Ø Universal Support
+
100-150Ø Adj Horizontal Terminal
or
100/150Ø Horizontal Terminal
Depending on installation
100-150Ø 1000mm Length
100-150Ø 450mm Length
100-150Ø 250mm Length
100-150Ø Adj 300-500 or 500-800mm
100-150Ø 45° Bend
100-150Ø 90° Bend
Adj Universal Collar