DORCHESTER DR-LP 30, DR-LP 40, DR-LP 45, DR-LP 60, DR-LP 75 User guide

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Page 1

Dorchester DR-LP Range

of Hot Water Storage Heaters

Open Flue, Direct Gas Fired Hot Water Storage

Heaters with Permanent Pilot Ignition

for Domestic Hot Water Installations

Installation, Commissioning

and Servicing Instructions

DORCHESTER DR-LP 30, 40, 45, 60, 75, 95 Models

NOTE: THESE INSTRUCTIONS MUST BE READ AND UNDERSTOOD BEFORE INSTALLING, COMMISSIONING, OPERATING OR SERVICING EQUIPMENT.

THIS WATER HEATER IS FOR USE ON GROUP H NATURAL GAS (2

LPG (3

FAMILY) I3+. PLEASE ENSURE RELEVANT INFORMATION REQUIRED WITHIN

FAMILY) I2H OR

DOCUMENT IS FOUND RELATING TO SPECIFIC GAS TO BE FIRED BEFORE FIRING HEATER.

THIS WATER HEATER COMPLIES WITH ALL RELEVANT EUROPEAN DIRECTIVES.

PUBLICATION NO. 500001136 (0307 246) ISSUE ‘A1

JUNE 2010

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Table of contents

1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - 7

1.1 About the water heater - - - - - - - - - - - - - - - - - - - - - - - - - - - 7

1.2 What to do if you smell gas- - - - - - - - - - - - - - - - - - - - - - - - - 7

1.3 Regulations - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7

1.4 Target groups - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8

1.5 Maintenance - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 9

1.6 Forms of notation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 9

1.7 Overview of this document - - - - - - - - - - - - - - - - - - - - - - - - 10

2 Functioning of the water heater - - - - - - - - - - - - - - - - 11

2.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 11

2.2 Functional description of the water heater - - - - - - - - - - - - - - - - 12

2.3 Heating cycle of the water heater - - - - - - - - - - - - - - - - - - - - - 13

2.4 Protection for the water heater - - - - - - - - - - - - - - - - - - - - - - 13

2.4.1 Gas control - - - - - - - - - - - - - - - - - - - - - - - - - - 13

2.4.2 Thermocouple- - - - - - - - - - - - - - - - - - - - - - - - - 13

2.4.3 Water temperature protection - - - - - - - - - - - - - - - - - 13

2.4.4 Combustion products discharge safety device - - - - - - - - - 14

2.5 Safety of the installation - - - - - - - - - - - - - - - - - - - - - - - - - 14

2.5.1 Unvented installation - - - - - - - - - - - - - - - - - - - - - 14

2.5.2 Vented installation- - - - - - - - - - - - - - - - - - - - - - - 14

2.5.3 Temparature and Pressure valve (T&P valve) - - - - - - - - - 14

2.6 Indicators and Alarms - - - - - - - - - - - - - - - - - - - - - - - - - - 15

2.6.1 Volt Free Contacts - - - - - - - - - - - - - - - - - - - - - - 15

2.7 Options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 15

2.7.1 LPG- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 15

2.7.2 Unvented Supply - - - - - - - - - - - - - - - - - - - - - - - 15

2.7.3 Top to Bottom Circulation - - - - - - - - - - - - - - - - - - - 15

3 Installation - - - - - - - - - - - - - - - - - - - - - - - - - - - 17

3.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 17

3.2 Packaging - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 19

3.3 Environmental conditions- - - - - - - - - - - - - - - - - - - - - - - - - 19

3.3.1 Working clearances - - - - - - - - - - - - - - - - - - - - - - 19

3.3.2 Humidity and ambient temperature- - - - - - - - - - - - - - - 19

3.3.3 Maximum floor loading - - - - - - - - - - - - - - - - - - - - 20

3.4 Technical specifications - - - - - - - - - - - - - - - - - - - - - - - - - 20

3.5 Installation diagrams - - - - - - - - - - - - - - - - - - - - - - - - - - - 22

3.6 Water connections Unvented - - - - - - - - - - - - - - - - - - - - - - - 22

3.6.1 Cold water side - - - - - - - - - - - - - - - - - - - - - - - - 22

3.6.2 Top to bottom recirculating pump - - - - - - - - - - - - - - - 22

3.6.3 Hot water side- - - - - - - - - - - - - - - - - - - - - - - - - 23

3.6.4 Drain valve - - - - - - - - - - - - - - - - - - - - - - - - - - 24

3.6.5 Circulation pipe - - - - - - - - - - - - - - - - - - - - - - - - 24

3.7 Water connections Vented - - - - - - - - - - - - - - - - - - - - - - - - 24

3.7.1 Cold water side - - - - - - - - - - - - - - - - - - - - - - - - 24

3.7.2 Top to bottom recirculating pump - - - - - - - - - - - - - - - 24

3.7.3 Hot water side- - - - - - - - - - - - - - - - - - - - - - - - - 24

3.7.4 Circulation pipe - - - - - - - - - - - - - - - - - - - - - - - - 25

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3.8 Gas connection - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 25

3.9 Flue gas discharge - - - - - - - - - - - - - - - - - - - - - - - - - - - - 25

3.9.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - 25

3.9.2 Fitting the draught diverter - - - - - - - - - - - - - - - - - - - 26

3.9.3 Flue gas thermostat assembly - - - - - - - - - - - - - - - - - 27

3.10 Electrical connection - - - - - - - - - - - - - - - - - - - - - - - - - - - 27

3.10.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - 28

3.10.2 Mains power - - - - - - - - - - - - - - - - - - - - - - - - - - 29

3.11 Conversion to a different gas category - - - - - - - - - - - - - - - - - - - 29

3.11.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - 30

3.11.2 Conversion to a different gas category - - - - - - - - - - - - - 30

3.12 Checking the supply pressure and burner pressure - - - - - - - - - - - - 32

4 Filling and draining - - - - - - - - - - - - - - - - - - - - - - - 35

4.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 35

4.2 Filling the water heater - - - - - - - - - - - - - - - - - - - - - - - - - - 36

4.2.1 Filling unvented installations - - - - - - - - - - - - - - - - - - 36

4.2.2 Filling vented installations- - - - - - - - - - - - - - - - - - - - 36

4.3 Draining the water heater - - - - - - - - - - - - - - - - - - - - - - - - - 36

4.3.1 Draining unvented installations - - - - - - - - - - - - - - - - - 36

4.3.2 Draining vented installations - - - - - - - - - - - - - - - - - - 37

5 Controls- - - - - - - - - - - - - - - - - - - - - - - - - - - - - 39

5.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 39

5.2 Control panel - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 39

5.3 Explanation of the symbols - - - - - - - - - - - - - - - - - - - - - - - - 40

5.4 On/Off-switch - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 40

5.5 Control thermostat - - - - - - - - - - - - - - - - - - - - - - - - - - - - 40

5.6 Flue gas thermostat reset button - - - - - - - - - - - - - - - - - - - - - 40

6 Error states of the water heater- - - - - - - - - - - - - - - - - 43

6.1 Error states - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 43

7 Starting up and shutting down - - - - - - - - - - - - - - - - - 45

7.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 45

7.2 Starting up - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 45

7.3 Shutting down- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 46

7.3.1 Shut the water heater down for brief periods ("OFF mode") - - - 46

7.3.2 Isolate the water heater from the power supply - - - - - - - - - 46

7.3.3 Shut the water heater down for a longer period - - - - - - - - - 46

7.4 Heating cycle - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 46

8 Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - 49

8.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 49

8.2 Troubleshooting table for general errors - - - - - - - - - - - - - - - - - - 50

8.3 Troubleshooting table 'no hot water' - - - - - - - - - - - - - - - - - - - - 52

8.4 Troubleshooting table 'insufficient hot water' - - - - - - - - - - - - - - - - 53

9 Maintenance - - - - - - - - - - - - - - - - - - - - - - - - - - 55

9.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 55

9.2 Preparing for maintenance - - - - - - - - - - - - - - - - - - - - - - - - 55

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9.3 Water-side maintenance - - - - - - - - - - - - - - - - - - - - - - - - - 55

9.3.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - 55

9.3.2 Checking the anodes - - - - - - - - - - - - - - - - - - - - - 55

9.3.3 Descaling and cleaning the heater - - - - - - - - - - - - - - - 56

9.4 Gas-side maintenance - - - - - - - - - - - - - - - - - - - - - - - - - - 57

9.4.1 Introduction - - - - - - - - - - - - - - - - - - - - - - - - - - 57

9.4.2 Cleaning the burners - - - - - - - - - - - - - - - - - - - - - 57

9.4.3 Cleaning the injectors - - - - - - - - - - - - - - - - - - - - - 57

9.4.4 Checking the flue baffles - - - - - - - - - - - - - - - - - - - 57

9.5 Finalising maintenance- - - - - - - - - - - - - - - - - - - - - - - - - - 57

A DR-LP electrical diagram - - - - - - - - - - - - - - - - - - - - 59

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6 Instruction manual DR-LP

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1 Introduction

About the water heater

1.1 About the water heater

0063

1.2 What to do if you smell gas

This manual describes how to install, service and use an DR-LP-water heater. An DR-LP water heater is a gas-fired open water heater without a fan. The DRLP-water heater is fitted with a combustion products discharge safety device and falls into the water heater category B water heater's identification plate. The information in this manual is applicable to types DR-LP: 30, 40, 45, 60, 75, 95.

The construction and fittings of each water heater conform to the European standard for gas-fired storage water heaters for sanitary use (EN 89). The water heaters are compliant with the European Directive on Gas Appliances and thereby authorised to bear the CE mark.

Warning

Read this manual carefully before commissioning the water heater. Failure to read the manual and to follow the printed instructions may lead to personal injury and damage to the water heater.

Warning

Whenever there is a smell of gas:

No naked flames! No smoking!

Avoid causing sparks! Do not use any electrical equipment or switch, i.e. no telephones, plugs or bells!

. This information is located on the

11B S

Shut off the mains gas supply!

Open windows and doors!

Warn occupants and leave the building!

After leaving the building, alert the gas distribution company or installer.

1.3 Regulations Gas Safety Installations and Use Regulations 1998, (As amended). It is law

that all gas appliances are installed by competent persons, in accordance with the above regulations. Failure to install appliances correctly could lead to prosecution. It is in your own interest, and that of safety, to ensure that this law is complied with.

The installation of the boiler MUST be in accordance with the relevant requirements of the Gas Safety Regulations, Building Regulations, IEE Regulations and the Water Supply (water fittings) Regulations.

The installation should also be in accordance with any relevant requirements of the HSE, local gas region and local authority and the relevant recommendations of the following documents:

British Standards

• BS 6891: Specification for installation of low pressure gas pipework of up to 28 mm (R1) in domestic premises (2nd family gas). For larger installations see IGE/UP/2 below.

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• BS 6798: Specification for installation of gas-fired boilers of rated input not exceeding 70 kW net.

• BS 6644: Specification for installation of gas-fired hot water boilers of rated inputs between 60 kW and 2 MW (2nd and 3rd family gases).

• BS 6700: Specification for design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages.

• BS EN 806-2: Specification for installations inside buildings conveying water for human consumption. Part 2: Design.

• BS 5546: Specification for installation of hot water supplies for domestic purposes, using gas-fired appliances of rated input not exceeding 70 kW.

• BS 5440: Installation and maintenance of flues and ventilation for gas appliances of rated input not exceeding 70 kW net (1st, 2nd and 3rd family gases). Part 1: Flues. Part 2: Ventilation.

Institute of Gas Engineers and Managers 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 pipework, boosters and compressors on industrial and commercial premises.

• IGE/UP/10 Installation of gas appliances in industrial and commercial premises. Part 1: flued appliances.

CIBSE Publications:- "CIBSE Guide"

Section B4 : Water Service Systems.

1.4 Target groups The three target groups for this manual are:

• (end) users;

•installers;

• service engineers.

Symbols on each page indicate the target groups for whom the information is intended. See Table 1.1.

Table 1. 1 Symbols for each target group

Symbol Target groups

(End) user

Installer

Service and maintenance engineer

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Maintenance

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1.5 Maintenance A service should be carried out at least once a year, both on the water side and

on the gas side. Maintenance frequency depends, among other things, on the water quality, the average burning time per day and the set water temperature.

n Note

To determine the correct maintenance frequency, it is recommended to arrange for the service engineer to check the water heater on both the water and gas side, three months after installation. Based on this check, the best maintenance frequency can be determined.

n Note

Regular maintenance extends the service life of the water heater.

Both the end user and the service engineer are responsible for regular maintenance. They will need to establish clear agreements on this.

n Note

If the water heater is not regularly maintained, the warranty will become void.

1.6 Forms of notation The following notation is used in this manual:

n Note

Important information.

cCaution

Ignoring this information can lead to the water heater being damaged.

Warning

Failure to carefully read this information may lead to danger of personal injury and serious damage to the water heater.

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1.7 Overview of this document

Tab le 1.2 Content of document

Chapter Target groups Description

2 Functioning of the water heater

3Installation

4 Filling and draining

Table 1.2 provides an overview of the contents of this document.

This chapter describes how the water heater functions.

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This chapter describes the installation activity to be completed

before you actually start up the water heater. Instructions are also provided for the installation and/or service engineer on converting the water heater to other types of gas.

This chapter describes how to fill and drain the water heater.

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5 Controls

6 Error states of the water heater

7 Starting up and shutting down

8 Troubleshooting

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This chapter describes the water heater’s control panel and how to use it.

This chapter describes each status (state) that the water heater may be in and how to respond, if necessary.

This chapter describes how to start up the water heater and how to shut it down for a brief or long period of time. The general heating cycle of the water heater is also described.

This chapter is mainly intended for the installer and the service engineer. It describes water heater errors. These errors are indicated on the display. A table of possible causes and solutions is provided. End users may also refer to this additional information about the water heater.

9 Maintenance

This chapter sets out the maintenance tasks to be carried out during a service.

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2 Functioning of the

water heater

2.1 Introduction This chapter successively covers the following topics:

• Functional description of the water heater

• Heating cycle of the water heater

• Protection for the water heater

• Safety of the installation

• Indicators and Alarms

• Options

Introduction

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Functioning of the water heater

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2.2 Functional description of the water heater

Legend

a flue gas discharge

b draught diverter

c anodes

d flue tubes

e flue gas thermostat sensor

f flue gas thermostat

g flue baffles

h insulation layer

i hot water tank

j cleaning opening

k drain valve

l combustion chamber

m radiation shield/condensation

tray

n gas control

o hot water outlet

p safety thermostat sensor

q high-limit thermostat sensor

r control panel

s control thermostat

t high-limit thermostat

u control thermostat sensor

v safety thermostat

w cold water inlet

x piezo igniter

y thermo-couple

z pilot burner

A igniter electrode

B bar burners/burner tray

Figure 2.1 shows a cut-away view of the water heater.

f g

h i

m n

z A

IMD-0364

Figure 2.1 Cut-away view of the water heater

In this water heater the cold water enters the bottom of the it via the cold water inlet w. The heat of combustion is transferred to the water through the combustion chamber l and flue tubes d. The heated tap water leaves the heater through the hot water outlet o. Once the water heater is completely filled with water, it remains constantly under water supply pressure. As hot water from the water heater is consumed, it is continuously replenished with cold water.

The water heater is fitted with a igniter electrode A which ignites the pilot burner z. The gas that fuels the combustion flows via the gas control n into the manifold, in which Injectors are located. Via these injectors, the gas enters the bar burners B. Together the bar burners constitute the burner tray. As the gas is injected into the bar burners, the primary air required for combustion is also drawn in When the gas/air mixture starts to flow, it is ignited by the pilot burner.

(1)

. Additional air is drawn through the openings in the burner tray.

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Heating cycle of the water heater

The flue gases arising from combustion here are drawn upwards through the flue tubes d. Flue baffles g are located in the flue tubes. These slow down the flue gas exhaust, improving the heat transfer efficiency. The flue gases leave the water heater via the draught diverter b. A radiation shield/condensation tray m is fitted under the burner tray. This prevents overheating of the floor surface under the water heater and serves as a collection tray for condensate.

The insulation layer h prevents heat loss. The inside of the hot water tank is enamelled to protect against corrosion. The anodes c provide additional protection.

2.3 Heating cycle of the

water heater

2.4 Protection for the

water heater

2.4.1 Gas control

The water heater is regulated by a control thermostat. The control thermostat monitors the water temperature (T activated as soon as T value for T

As soon as T thermostat closes, causing the main valve on the gas control to open. The gas mixes with the air it draws along. This mixture is ignited by the pilot burner and the water becomes heated. As soon as T ceases, the thermostat opens again and the heating cycle stops.

The control thermostat has a certain margin both when closing and opening, referred to as the hysteresis. The hysteresis cannot be adjusted.

The water heater is protected by means of the following:

• the Gas Control

• the Thermocouple

• the Water Temperature Safeguard

• the Combustion products discgarge safety device

The gas control has 2 valves for safety purposes:

1. The main valve, which controls the gas supply to the burner tray and which is switched via the On/Off-switch circuit and the control, high-limit and flue gas thermostats. This circuit is powered by the supply voltage.

2. The safety valve, which controls the gas supply to the pilot burner and which is switched via the thermocouple circuit and the safety thermostat. This circuit is powered by the millivolt potential from the thermocouple that is located in the pilot flame. Whenever the safety valve closes, the main valve also closes.

can be adjusted using the control thermostat (40°C ... 70°C).

set

drops below T

water

falls below the specified threshold value (T

water

). The water heater's heating cycle is

water

set

there is a demand for heat and the control

set

exceeds T

water

, the heat demand

set

). The

2.4.2 Thermocouple

1. To prevent gas flowing when there is no combustion, a thermocouple is fitted. As a result of the presence of the (permanent) pilot flame, the thermocouple maintains a millivoltage potential which keeps the gas control's safety valve open.

2. If the pilot flame goes out, this voltage disappears and the gas control's safety valve closes, interrupting the gas supply to the burner tray.

2.4.3 Water temperature protection

To ensure a safe water temperature is not exceeded, the high-limit thermostat sensor is installed at the top of the water heater. In the event of stratification of the water temperature, the temperature at the top of the water heater can be considerably higher than the set temperature for the hot water.

In the event that both the control and maximum thermostats should fail, there is also a safety thermostat.

1. The gas flow is accelerated through the narrow opening in the injector. This creates a vacuum, which also draws in air, through the Venturi effect.

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Functioning of the water heater

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Table 2.1 explains how the high-limit and safety thermostats respond to the

sensors.

Tab le 2.1 Temperature protection

Protection Description

High-limit thermostat If the high-limit thermostat sensor q detects a temperature greater

than 84°C, the high-limit thermostat opens and the gas control's main valve circuit is broken, closing the valve. The heating cycle stops until the high-limit thermostat closes again. At this point the gas control opens again and the heating cycle is repeated. The high-limit protection also prevents excessive scale forming in the water heater.

Safety thermostat If the safety thermostat sensor p detects a temperature greater than 93°C, the

safety thermostat opens. The gas control's safety valve circuit is broken and the safety and main valve both close. Combustion immediately ceases and the pilot flame also goes out.

In order to re-start the water heater, the pilot flame must be re-lit.

2.4.4 Combustion products discharge safety device

The flue gases are drawn outside via the draught diverter b and the flue gas discharge a. To prevent the flue gases from flowing back into the installation room, the discharge ducting is monitored by a feature called the combustion products discharge safety device. For this purpose a flue gas thermostat sensor e complete with flue gas thermostat f is fitted in the draught diverter. Under normal circumstances this sensor measures the ambient temperature. However, if the chimney is not drawing sufficiently (for example, due to a blockage in the chimney), the flue gases will 'reflux' and flow back past the flue gas thermostat sensor. The sensor then detects an excessive temperature and the flue gas thermostat will open. The circuit of the main valve of the gas control is interrupted and the valve closes, which forces the heating cycle to stop. The flue gas discharge thermostat will be locked out and the water heater will require a manual reset before it can be re-started.

2.5 Safety of the installation

2.5.1 Unvented installation

2.5.2 Vented installation

2.5.3 Temparature and Pressure valve (T&P valve)

With an unvented installation, an expension valve and expansion vessel prevent excessive pressure in the water heather. This prevents damage of the water heater. A non-return valve prevents excessive pressure in the water supply system. This valve also prevents water from flowing backwards from the heater into the cold water supply system. The pressure reducing regulates the water supply pressure to a normal operating pressure of 3.5 bar. The components are fitted to the cold water pipe. See paragraph 3.6.1 Cold water side.

With a vented installation, excess pressure is taken up by the open water tank. The level of the water determines the working pressure which may not exceed 8 bar.The installation must also be fitted with an open vent from the hot water pipe. Ideally the vent pipe should be linked to a separate tundish/drain or else to the cold water storage tank. A safety valve should also be fitted to the water heather. See paragraph 3.6.3 Hot water side.

A T&P valve is mandatory in an 'unvented' installation.

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Indicators and Alarms

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A T&P valve monitors the water pressure in the water heater and the water temperature at the top of it. If the pressure in the water heater becomes excessive (> 7 bar) or the water temperature is too high (>97°C), the valve will open. The hot water will immediately flow out of the heater. Because the water heater is under water supply pressure, cold water will automatically flow into it. The valve remains open until the unsafe situation has been averted. A connecting point for a T&P valve is standard on the water heater. See paragraph

3.6.3 Hot water side

2.6 Indicators and

Alarms

2.6.1 Volt Free Contacts

Volt free contacts are supplied as standard to give remote indication/alarm of 'normal run' and 'lockout'. The 'lockout' indication includes shut down due to operation of the safety thermostat, loss of flame and failure to ignite.

2.7 Options The heaters can be supplied with the following additional variations, either

ready fitted or for site fitting:

2.7.1 LPG

The heaters can be supplied adjusted for use on propane or butane, see section

3.12. It is most important that the heater is correctly adjusted for the gas to be fired.

2.7.2 Unvented Supply

The heaters can be supplied with a purpose designed and sized unvented kit comprising pressure reducing valve, non-return valve, expansion vessel, expansion relief valve and pressure/temperature relief valve, to enable the heater to be coupled directly to the mains water. For details see 2.5.1, 2.5.3 and

3.6.

2.7.3 Top to Bottom Circulation

In order to give enhanced temperature control to aid compliance with the HSE guidance and the DHss Code of Practice for 'The Control of Legionellae in Health Care Premises', a pump circulation kit can be supplied comprising 230 volt single phase pump, non-return valve, pipe work and sufficient fittings to contact between the hot water flow and the bottom connection. For details see section 3.5 of this manual.

Instruction manual DR-LP 15

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Functioning of the water heater

gis

16 Instruction manual DR-LP

Page 17

Introduction

3 Installation

Warning

The installation should be carried out by an authorised installation engineer in compliance with the official local regulations imposed by the gas, water and power supply companies and the fire service.

The water heater may only be installed in a room which complies with the requirements stated in national and local ventilation regulations.

See also paragraph 1.3 Regulations.

3.1 Introduction This chapter describes the installation activities to be carried out before the

water heater may be started up, namely:

• Packaging;

• Environmental conditions;

• Technical specifications;

• Water connections Unvented;

• Water connections Vented;

• Gas connection;

• Flue gas discharge;

• Electrical connection;

• Conversion to a different gas category;

• Checking the supply pressure and burner pressure;

n Note

Starting up the water heater is described in chapter 7 Starting up and

shutting down.

Figure 3.1 shows a plan and elevation drawing of the water heater.

Instruction manual DR-LP 17

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Installation

IMD-0365

Figure 3.1 Plan and elevation of the water heater

18 Instruction manual DR-LP

Page 19

Packaging

3.2 Packaging To avoid damaging the water heater, remove the packaging carefully.

We recommend unpacking the water heater at or near its intended location.

cCaution

The water heater may only be manoeuvered in an upright position. Take care that the water heater is not damaged after unpacking.

cCaution

3.3 Environmental

conditions

3.3.1 Working clearances

The water heater may not be used in rooms where chemical substances are stored or used due to the risk of explosion and corrosion to the water heater. Some propellants, bleaching agents, degreasing agents etc. disperse vapours which are explosive and/or which cause accelerated corrosion. If the water heater is used in a room in which such substances are present, the warranty will be void.

DR-LP-water heaters are open water heaters and may only be placed in an open boiler room. They fall under category B

For access to the water heater it is recommended that the following clearances are observed (see Figure 3.1):

• AA: around the water heater's control column and cleaning openings: 100 cm.

• BB: around the water heater itself: 50 cm.

• Above the water heater (room to replace the anodes):

- 100 cm if using fixed anodes or

- 50 cm if using flexible anodes.

If the available clearance is less than 100 cm, flexible magnesium anodes may be ordered from Hamworthy heating limited.

11B S

n Note

When installing the water heater, be aware that any leakage from it and/or connections can cause damage to the immediate environment or floors below the level of the boiler room. If this is the case the water heater should be installed above a wastewater drain or in a suitable metal leak tray. The leak tray must have an appropriate wastewater drain and must be at least 5 cm deep with a length and width at least 5 cm greater than the diameter of the water heater.

3.3.2 Humidity and ambient temperature

The boiler room must be frost-free or be protected against frost. Table 3.1 shows the environmental specifications which must be observed to guarantee correct functioning of the water heater.

Tab le 3.1 Humidity and ambient temperature specifications

Humidity and ambient temperature

Humidity max. 93% RH at +25°C

Ambient temperature Functional: 0 ≤ t ≤ 60°C

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Installation

3.3.3 Maximum floor loading

Because of the weight of the water heater when filled (see Ta bl e 3 .2 ), verify that the maximum floor loading for the boiler room is not exceeded.

Table 3.2 Weight specifications with regard to maximum floor loading

Weight of the water heater filled with water

DR-LP 30 DR-LP 40 DR-LP 45 DR-LP 60 DR-LP 75 DR-LP 95

504 kg 578 kg 507 kg 573 kg 522 kg 523 kg

3.4 Technical specifications

Table 3.3 Dimensions DR-LP

Dimension & Description DR-

A. Height including draught diverter (mm) 1900 2100 1900 20402025 2085

B. Height excluding draught diverter (mm) 1760 1960 1760190017951810

D. Diameter of the water heater (mm) 710 710 710 710 710 710

E. Depth including control column (mm) 800 800 800 80 0 800 800

F. Width of water heater incl. draught diverter (mm) 1100 110011001100 1105 1105

G. Flue gas outlet diameter (mm) 150 150 180 180 225 225

J. Height flue gas discharge (mm) 1840 2040 1840 2040 1935 2010

K. Height of the gas connection (mm) 205 205 205

M. Height of the cold water supply (mm) 565 565 565 505575590

N. Height of the hot water outlet (mm) 1605 1810 1605 1750 1640 1655

The water heater is supplied without accessories. Check the dimensions and other specifications for any accessories to be used against Figure 3.1 and tables Ta bl e 3 .3 through Ta bl e 3 .6 .

LP 30

DRLP 40

DRLP 45

DRLP 60

205205205

DRLP 75

DRLP 95

P. Height of the cleaning opening centre (mm) 730730730 670 740 765

R. Height of the drain valve centre (mm) 500 515 500 455 525 540

S. Height of the T&P plug centre (mm) 1550 1760 1550 1700 15951600

1. Cold water supply connection (external thread) R 1

2. Hot water outlet connection (internal thread) Rp 1 1/

3. Gas control connection (internal thread) Rp 3/

4. Drain valve connection (internal thread) Rp 1 1/

5. T&P valve connection (internal thread) 1" NPT 1" NPT

6. Dimension of cleaning and inspection openings (mm) Ø 100

Rp 3/

20 Instruction manual DR-LP

Page 21

Technical specifications

Tab le 3.4 Specifications for gas categories, water heater category: II

Description Unit DR-LP30DR-LP40DR-LP45DR-LP60DR-LP75DR-LP

Gas category 2H: G20 - 20 mbar

Diameter of orifices mm 3.20 3.20 3.10 2.95 3.20 3.20

Diameter of pilot flame orifice mm 0.56/

0.41

(1) = Blanking plate (2) = Burner pressure regulator

Nominal load (gross) kW 41.4 55.4 65.2 81.0 96.4 124.2

Nominal output kW 31.7 41.9 49.3 61.2 72.9 93.9

Burner pressure

Gas consumption

Gas category 3+: G30 - 30 mbar

Diameter of orifices mm 1.70 1.70 1.70 1.50 1.7

Diameter of pilot flame orifice mm 0.25 0.25 0.25 0.25 0.25 0.25

(1) = Blanking plate (2) = Burner pressure regulator

(1)

(2)

1 or 2222222

mbar8.58.58.58.58.58.5

m³/h 4.0 5.4 6.3 7.9 9.4 12.1

1 or 2111111

2H3+

0.56/

0.41

0.56/

0.41

0.56/

0.41

0.56/

0.41

0 1.70

0.56/

0.41

Nominal load (gross) kW 40.9 54.2 66.9 79.2 94.3 121.2

Nominal output kW 32.0 42.0 51.8 61.4 73.1 93.9

Burner pressure

Gas consumption

Gas category 3+: G31 - 37 mbar

(1) = Blanking plate (2) = Burner pressure regulator

Nominal load (gross) kW 37.6 50.1 62.1 76.2 87.8 110.9

Nominal output kW 29.4 38.7 48.0 58.9 67.9 85.7

Diameter of orifices mm 1.70 1.70 1.70 1.50 1.7

Burner pressure

Gas consumption

1. If using a blank plate instead or burner pressure regulator, it is assumed that the burner pressure is equal to the supply pressure. In practice however the burner pressure will be lower

2. Based on 1013.25 mbar and 15°C

(1)

(2)

(1)

(2)

mbar------

kg/h 3.0 4.0 5.0 5.9 7.0 9.0

1or 2111111

0 1.70

mbar------

kg/h 2.7 3.7 4.5 5.6 6.4 8.1

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Installation

Tab le 3.5 General and electrical data

Description Unit DR-LP30DR-LP40DR-LP45DR-LP60DR-LP75DR-LP

Storage Capacity litres 324 374 312 351 291 265

Maximum operating pressure bar888888

Maximum operating pressure unvented bar 5,5 5,5 5,5 5,5 5,5 5,5

Nominal operating pressure unvented bar 3,5 3,5 3,5 3,5 3,5 3,5

Number of anodes - 222334

Empty Weight kg 195 221 209 238 244 270

Heating time T = 45°C min. 32 28 20 18 13 9

Number of anodes - 334477

Number of bar burners/orifices - 3 45779

Number of flue tubes/baffles - 5 6 7 9 12 16

Electrical power consumption W 30

Supply voltage ACS

(VAC)

Mains frequency Hz 50 (±1 Hz)

3.5 Installation diagrams Figure 3.2 shows the water and gas connection diagrams for unvented and

vented installations. The following paragraphs, describing the connections in detail, make reference to these diagrams.

3.6 Water connections Unvented

3.6.1 Cold water side

See a in Figure 3.2.

1. Fit an approved stop valve i on the cold water side as required by regulations. See also paragraph 1.3 Regulations.

2. The maximum working pressure of the water heater is 8 bar. The expansion valve regulates the pressure to 5.5 bar. The operatiing pressure is 3.5 bar. Fit an approved pressure-reducing valve a.

3. Fit a non-return valve e and an expansion vessel b.

4. Fit an expension valve n and connect the discharge to a drain via tundish.

230 (-15% +10%)

3.6.2 Top to bottom recirculating pump

You can connect a top to bottom recirculation pump to prevent stratification of the water in the water heater.

1. Fit a pipe (Ø 22 mm), a stop valve d and a top to bottom recirculation pump k.

2. Fit non-return valve e.

3. Fit stop valves i.

22 Instruction manual DR-LP

Page 23

Legend

a pressure-reducing valve

(mandatory)

b expansion vessel (mandatory)

c T&P valve (mandatory)

ca) safety valve

d stop valve (recommended)

e non-return valve (mandatory)

ea) non-return valve

f circulation pump (optional)

g drain valve

h gas valve (mandatory)

i stop valve (mandatory)

j temperature gauge

(recommended)

k top to bottom recirculation

pump (optional)

l draught diverter

m hot water draw-off points

n expension valve (mandatory)

o water tank

p float valve

q 3-way venting valve (optional)

r overflow pipe

a cold water supply

b hot water outlet

c circulation pipe

d gas supply

e flue gas discharge

Water connections Unvented

UNVENTED

IMD-0314

VENTED

IMD-0315

Figure 3.2 Installation diagrams

3.6.3 Hot water side

See b in Figure 3.2.

n Note

Insulating long hot water pipes prevents unnecessary energy loss.

1. Optional: fit a temperature gauge j to be able to check the temperature of the tap water.

2. Fit the T&P valve c.

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Installation

3. Fit a stop valve i in the hot water outlet pipe, for use when servicing.

3.6.4 Drain valve

1. Fit the standard drain valve g supplied.

2. Refer to paragraph 3.6.5 if a circulation pipe is to be fitted. Otherwise, fit the sealing nut and gasket supplied with the drain valve. See Figure 3.3.

3.6.5 Circulation pipe

See c in Figure 3.2. and Figure 3.3.

If an immediate flow of hot water is required at draw-off points, a circulation

pump can be installed. This improves comfort and reduces water wastage.

1. Fit a circulation pump f of the correct capacity for the length and resistance of the circulation system.

2. Fit a non-return valve ea downstream the circulation pump to guarantee the direction of circulation.

3. Fit two stop valves for servicing d.

4. Connect the circulation pipe to the T-piece on the drain valve g. See

Figure 3.3.

IMD-0122

Figure 3.3 Drain valve

3.7 Water connections Vented

3.7.1 Cold water side

3.7.2 Top to bottom recirculating pump

3.7.3 Hot water side

See a in Figure 3.2.

• Fit an approved stop valve (recommended) on the cold water side between the water tank o and the water heater i as required by regulations. Ideally the vent pipe should be linked to a separate tundish/drain or else to the cold water storage tank. See also paragraph 1.3 Regulations.

You can connect a top to bottom recirculation pump to prevent stratification of the water in the water heater.

1. Fit a pipe (Ø 22 mm), a stop valve d and a top to bottom recirculation pump k.

2. Fit non-return valve e.

3. Fit stop valves i.

See b in Figure 3.2.

n Note

Insulating long hot water pipes prevents unnecessary energy loss.

1. Fit the safety valve ca.

2. Optional: fit a temperature gauge (recommended) j to be able to check the temperature of the tap water.

3. Fit a stop valve (mandatory) i in the hot water outlet pipe, for use when servicing.

4. Refer to paragraph 3.7.4 if a circulation pipe is to be fitted.

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Page 25

3.8 Gas connection

Gas connection

3.7.4 Circulation pipe

See c in Figure 3.2.

If an immediate flow of hot water is required at draw-off points, a circulation pump can be installed. This improves comfort and reduces water wastage.

1. Fit a circulation pump f of the correct capacity for the length and resistance of the circulation system.

2. Fit a non-return valve ea downstream the circulation pump to guarantee the direction of circulation.

3. Fit two stop valves for servicing d.

4. Connect the circulation pipe to the T-piece on the drain valve g. See

Figure 3.3.

Warning

Gas installation may only be carried out by an authorised installation engineer in compliance with the general regulations imposed by the gas company. See also paragraph 1.3 Regulations.

3.9 Flue gas discharge

3.9.1 Introduction

cCaution

Make sure that the diameter and length of the gas supply pipe is are large enough to supply sufficient capacity to the water heater.

See d in Figure 3.2.

1. Fit a gas valve (mandatory) h in the gas supply pipe.

2. Blow the gas pipe through before use, to be sure it is clean.

3. Close the gas valve.

4. Fit the gas supply pipe to the gas control.

Warning

Check for leaks after fitting.

Warning

The installation should be carried out by an authorised installation engineer, in compliance with the general and local regulations imposed by gas, water supply and power supply companies and the fire service. Refer also to paragraph 1.3 Regulations and documents.

When connecting the water heater to the chimney, the draught diverter l supplied with the water heater must be used. The standard flue gas thermostat and sensor that are supplied must be fitted in the draught diverter.

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Page 26

3.9.2 Fitting the draught diverter

Legend

a sealing ring

b fastening screws

c chimney pipe

d 45° bend

e holes to attach support bracket

f support bracket

n Note

To guarantee draught a chimney pipe with a lenght of at least 0.5 m should be fitted to the 45o bend.

Installation

The draught diverter can be positioned according to preference. After positioning, the draught diverter is secured using two screws b to the top surface of the water heater and also sits on a support bracket f attached to the side of the water heater. The assembly procedure is as follows:

> 0.5 m

a b

IMD-0123

Figure 3.4 Placing the draught diverter

1. Take the support bracket out of the bag.

2. Fit the support bracket f in such a way that it properly supports the draught diverter.

3. Drill two holes e (3.2 mm drill) for the support bracket screws.

4. Screw the support bracket tightly to the water heater.

5. Place the draught diverter in the support bracket and mark the centres for the two drill holes on the top surface of the water heater. Remove the draught diverter from the water heater.

6. Now drill two holes b into the top of the water heater (3.2 mm drill).

7. Place the sealing ring a on the water heater.

8. Screw the draught diverter tightly in place.

9. Fit:

- a 45° bend d onto the outlet of the draught diverter, followed by:

- a corrosion-resistant vertical chimney pipe c of at least 0.5 metre,

- the remaining flue components.

n Note

Use flue gas discharge materials that comply with the regulations. See paragraph 1.3 Regulations and documents.

n Note

Make sure that the chimney discharges into an area where this is permitted for this category of water heater.

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Page 27

Electrical connection

3.9.3 Flue gas thermostat assembly

Attached to the control column is a plastic bag containing the flue gas thermostat with sensor and related attachment materials. The cable from the sensor is already connected in the control column. The thermostat/bracket and sensor have yet to be fitted inside the draught diverter. See Figure 3.5.

Warning

If the flue gas thermostat is not (or is incorrectly) fitted/connected, the flue gas discharge will not be protected. An incorrectly fitted chimney can cause flue gases to backflow into the boiler room.

3.10 Electrical connection

Figure 3.5 Flue gas thermostat assembly

Fit the flue gas thermostat as follows:

1. Take the bracket 1 with thermostat and sensor 2 from the packaging.

2. Place the bracket in the draught diverter and screw the bracket and the sensor firmly in place.

3. Bend the cable clips 3 around the cable 4 of the flue gas thermostat.

Screw the cable clips 3 in place in the draught diverter and the water heater.

IMD-0137.

Warning

The installation should be carried out by an approved installation engineer in compliance with the general and local regulations imposed by the gas, water and power supply companies and the fire service. See also paragraph 1.3 Regulations.

Instruction manual DR-LP 27

Page 28

3.10.1 Introduction

Tab le 3.6 Electrical connecting block DR-LP

Installation

This paragraph covers the connectons of the 3.10.2 Mains power;

Figure 3.6 shows a front view of the electrical connecting block. Table 3.6

shows the associated connections.

Mains voltage Time clock

connection

123456789101112

LLL1NL2L

Time clock

power

Combustion

products

discharge

safety device

IMD-0366

Figure 3.6 Connecting block (connections 1 to 14 explained in Ta bl e 3 .6 )

In preparation, first remove the protective cover from the control column:

• Undo the 4 screws a and remove the protective cover 2 from the electrical section. The connecting block 3 is now visible.

n Note

Consult A DR-LP electrical diagram for electrical component connections.

28 Instruction manual DR-LP

Page 29

3.10.2 Mains power

The water heater is supplied without a power cable and isolator.

n Note

In order to receive electrical power, the water heater has to be connected to the mains voltage by means of a permanent electrical connection. A double pole isolator with contact gaps of at least 3 mm must be fitted local to the water heater. The power cable must have cores of at least 3 x 1.0 mm2.

1. Feed the power cable through the metric strain relief on the top of the control column.

2. Connect earth ( terminals 1 to 3 of the connecting block as set out in Ta bl e 3 .6 .

3. Tighten the strain relief so that the cable is clamped.

4. If you do not need to make any more connections, then fit the protective cap on the control column.

5. Connect the power cable to the isolator.

Warning

Leave the water heater disconnected until you are ready to start it up.

A), phase (L

Conversion to a different gas category

) and neutral (N) on the power cable to

3.11 Conversion to a different gas category

cCaution

The conversion may only by carried out by an authorised installation engineer.

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Page 30

3.11.1 Introduction

Legend

a cover plate

b locking strip

c orifice with stamped figures

Installation

If the water heater must operate on a family of gas (LP-gas or natural gas) other than the category of gas for which the water heater has been set up at the factory, the water heater will have be adapted using a special conversion kit. Converting the DR-LP water heaters is described in 3.11.2 Conversion to a

different gas category.

3.11.2 Conversion to a different gas category

Take care

The burner may be hot.

IMD-0196

Figure 3.7 Replacing the orifices

1. Disconnect the water heater from the power supply. See paragraph

7.3.2 Isolate the water heater from the power supply.

2. Shut off the gas supply.

3. Unscrew the cover plate a from the burner support.

4. Use a suitable tool to remove the locking strips b. Note: the locking strips have especially sharp edges. Withdraw the locking strips straight upwards.

5. The radiation shield / condensation tray can be temporarily loosened to simplify assembly of the burner.

6. Remove the burners one by one from their brackets at the front. To do this, you first move them away from you and then downwards. The orifices are then accessible.

7. Remove the orifices.

8. Select and fit the correct orifices from the conversion kit, by referring to

Ta bl e 3 .4 . The orifice diameter is shown on the orifice by means of stamped

figures c.

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Page 31

Conversion to a different gas category

Legend

See Figure 3.7 for 1 to 3.

d burner pressure regulator

e blank plate

f supply pressure test nipple

g burner pressure test nipple

h gas control valve

i burner pressure control cap

j burner pressure control

adjusting screw

Figure 3.8 Converting the gas control

9. Refit the burners back in their original position.

10. Re-fit the locking strips.

11. If the radiation shield /condensation tray was loosened, re-tighten it.

12. Check whether there is a burner pressure regulator d attached to the top of the gas control or simply a blank plate e.

13. Check with the help of the burner pressure in Table 3.4 whether a burner pressure regulator is required for the new gas category.

14. If the blank plate must be replaced with a burner pressure regulator or vice versa:

- Remove the existing blank plate e or burner pressure regulator d.

- Fit the new burner pressure regulator or blank plate supplied with the

conversion kit.

15. Check the burner pressure and supply pressure (see paragraph 3.12).

16. Remove the sticker showing the new gas category from the conversion kit, attach it below the water heater's rating plate. This clearly indicates that the water heater may no longer be run on the gas for which it was originally supplied.

17. Start up the water heater (see paragraph 7.2).

IMD-0137

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Page 32

3.12 Checking the supply pressure and burner pressure

Installation

n Note

Before you start up the water heater and/or begin to check the supply pressure and burner pressure, you must fill the water heater. For the filling procedure, please refer to paragraph 4.2 Filling the water heater.

cCaution

Before starting-up for the first time and following conversion, you must always check the supply pressure and burner pressure. If necessary, adjust these to be certain of optimum performance of the water heater.

n Note

The easiest way to check the gas pressures is by using two pressure gauges. This procedure assumes that these two gauges are available.

1. Switch off the power to the water heater and extinguish the pilot flame. See paragraph 7.3.2 Isolate the water heater from the power supply.

2. The supply pressure is checked using a test nipple f on the gas control (Figure 3.8). The manifold test nipple g is used for measuring the burner pressure. Sealing screws are located inside the test nipples. Loosen both sealing screws by a few turns. Do no completely undo them, as it may be awkward retightening them.

3. There are two test nipples on the gas control g.

n Note

All gas pipes should be bleeded and free of leakage.

4. Open the gas supply.

5. Connect a pressure gauge to the supply pressure test nipple f as soon as gas starts to flow from this nipple.

6. Switch on the power to the water heater using the isolator on the water heater.

7. Begin the ignition procedure by pressing and holding the white button on the gas control while repeatedly pressing the piezo igniter until the pilot flame ignites. The pilot flame can be seen through the inspection window above the burner tray.

8. Keep the white button pressed in for about 30 seconds before carefully releasing it. The pilot flame must now keep burning.

9. Set the control thermostat to the highest position (take note of the original setting) and set the On/Off-switch back to position I.

10. If there is no heat demand, then draw-off some hot water to initiate a heat demand.

11. The heating cycle will start and the burner tray will ignite after a short time.

Warning

If the pilot flame goes out during the ignition procedure or heating cycle, you must wait 5 minutes before repeating the ignition procedure.

12. After the burner tray has ignited, wait for approximately 1 minute before you start reading the dynamic pressures.

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Checking the supply pressure and burner pressure

13. Use the pressure gauge to read the supply pressure at the test nipple f. Refer to Ta bl e 3 .4 .

n Note

Consult the mains gas supply company if the supply pressure is not correct.

14. Use the pressure gauge to read the burner pressure at the burner pressure test nipple. Refer to Tab le 3 . 4.

n Note

If the burner pressure is not correct and the water heater is fitted with a blank plate (e), you will not be able to adjust the pressure. In this case, consult your installation engineer or supplier. If the water heater is fitted with a burner pressure regulator, then the pressure can be adjusted by following steps 15 to 20.

15. Remove the cap i from the burner pressure regulator d.

16. Adjust the burner pressure by turning the adjusting screw j, depending on the correction required:

- To reduce burner pressure, turn the adjusting screw anti-clockwise;

- To increase burner pressure, turn the adjusting screw clockwise;

17. Cover the opening of the adjusting screw and check the burner pressure against the target value from Ta bl e 3 .4 .

18. If the pressure reading is not correct, repeat steps 16 and 17 until the correct pressure is attained.

19. Re-fit the cap i on the burner pressure regulator.

20. Shut down the water heater by setting the On/Off-switch to the 0 position.

21. Shut off the gas supply.

22. Disconnect the two pressure gauges and re-tighten the sealing screws in the test nipples.

Instruction manual DR-LP 33

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Installation

34 Instruction manual DR-LP

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gis

4 Filling and draining

4.1 Introduction Topics covered in this chapter:

• Filling the water heater.

• Draining the water heater.

The components referred to in these sections are illustrated in Figure 4.1.

Legend

a pressure-reducing valve

(mandatory)

b expansion vessel (mandatory)

c T&P valve (mandatory)

ca) safety valve

d stop valve (recommended)

e check valve (mandatory)

ea) non-return valve

f circulation pump (optional)

g drain valve

h gas valve (mandatory)

i stop valve (mandatory)

j temperature gauge

(recommended)

k top to bottom recirculation

pump (optional)

l draught diverter

m hot water draw-off points

n expension valve (mandatory)

o water tank

p float valve

q 3-way venting valve (optional)

r overflow pipe

a cold water supply

b hot water outlet

c circulation pipe

d gas supply

e flue gas discharge

UNVENTED

VENTED

Introduction

IMD-0314

IMD-0315

Figure 4.1 Connection diagrams

Instruction manual DR-LP 35

Page 36

4.2 Filling the water heater

Filling and draining

gis

4.2.1 Filling unvented installations

To fill the water heater, proceed as follows.

1. Open the stop valve i on the hot water pipe and, if present, the stop valves d for the circulation pump.

2. Close the drain valve g.

3. Open the nearest hot water draw-off point m.

4. Open the stop valve i on the cold water side a so that cold water flows into the water heater.

5. Completely fill the water heater (when cold water flows at normal pressure from the nearest hot water draw-off point, the water heater is full).

6. Vent the entire installation of air, by opening all hot water draw-off points, for example.

7. The water heater is now under water supply pressure. There should be no water coming out of the expansion valve n nor the T&P-valve c. If this does happen, the cause might be:

- The water supply pressure is greater than the specified 3.5bar.

Check the correct pressure.

- The expansion valve in the cold water supply arrangement is defective

or incorrectly fitted.

4.2.2 Filling vented installations

4.3 Draining the water heater

4.3.1 Draining unvented installations

To fill the water heater, proceed as follows:

1. Open the stop valve i on the hot water pipe and, if present, the stop valves d for the circulation pump.

2. Close the drain valve g.

3. Open the nearest hot water draw-off point m.

4. Open the stop valve i on the cold water side a so that cold water flows into the water heater.

5. Completely fill the water heater (when cold water flows at normal pressure from the nearest hot water draw-off point, the water heater is full).

6. Vent the entire installation of air, by opening all hot water draw-off points, for example.

7. The water heater is now under water supply pressure. There should be no water coming out of the T&P-valve ca. If this does happen, the safety valve might be defective or incorrectly fitted.

For some procedures may require the water heater to be drained. Proceed as follows:

Some service activities require the water heater to be drained. The procedure is as follows:

1. Shut the water heater down by putting the On/Off switch to position 0.

2. Disconnect the water heater by putting switching the mains isolator off.

3. Shut off the gas supply h.

4. Close the stop valve i in the hot water pipe.

5. Close the supply valve in the cold water supply a.

36 Instruction manual DR-LP

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gis

Draining the water heater

6. Open the drain valve g.

7. Vent the water heater (or installation) so that it drains completely.

4.3.2 Draining vented installations

For some procedures may require the water heater to be drained. Proceed as follows:

Some service activities require the water heater to be drained. The procedure is as follows:

1. Shut the water heater down by putting the On/Off switch to position 0.

2. Switch the mains isolation off.

3. Shut off the gas supply h.

4. Close the stop valve i in the hot water pipe.

5. Close the stop valve between the water tank and the cold water inlet.

6. Open the drain valve g.

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Filling and draining

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5 Controls

5.1 Introduction Topics covered in this chapter:

• 5.2 Control panel;

• 5.3 Explanation of the symbols;

• 5.4 On/Off-switch;

• 5.5 Control thermostat;

• 5.6 Flue gas thermostat reset button.

5.2 Control panel Figure 5.1 illustrates the control panel. The panel consists of:

• an On/Off-switch;

• a control thermostat with rotary knob.

Introduction

Figure 5.1 The control panel

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Controls

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5.3 Explanation of the symbols

5.4 On/Off-switch Using the On/Off-switch, set the water heater to the ON mode ('I' position) or

Table 5.1 explains the icons on the control panel.

Table 5 . 1 Control panel icons

Symbol Name Explanation

On/Off switch Sets water heater mode to 'ON',

Temperature control Sets water temperature (T

OFF mode ('0' position). The water heater remains live, even when in the OFF mode. This keeps the weekly water heating program and/or Power Anode active.

'Week Program' or 'OFF'.

set

)

n Note

To electrically isolate the water heater, you must use the local switch between the water heater and the mains power supply.

5.5 Control thermostat Use the rotary knob on the control thermostat to set the desired water

temperature to between 40°C and 70°C. The knob rotates over a scale of 1 to

4. Ta bl e 5 . 2 shows the approximate temperature at each position.

Table 5 . 2 Temperature settings

5.6 Flue gas thermostat reset button

Position Temperature

A malfunction in the flue gas discharge, e.g. a blockage in the chimney, can lead to the flue gas thermostat locking out. This state is evident when the push button on the flue gas thermostat has been activated, see Figure 5.2. Once the cause has been removed and the sensor has cooled down sufficiently, press this push button to reset (if the sensor is not sufficiently cooled down, the flue gas thermostat will immediately lock out again). The water heater will then automatically start up again, if there is a demand. If this does not happen, refer to chapter 8 Troubleshooting for a complete troubleshooting guide.

≈ 40°C

≈ 50°C

≈ 60°C

≈ 70°C

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Take care

The draught diverter can be hot.

Flue gas thermostat reset button

Figure 5.2 Flue gas thermostat reset button

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Controls

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Error states

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6 Error states of the

water heater

6.1 Error states If the water heater has an error the heater will not operate. The frost protection

will also be out of operation.

If the water heater should go into an "error" state, you will be unable to continuosly draw hot water. These error conditions are divided into three groups:

• Gas control lock out errors

In this case the gas control's safety valve is closed, as a result of which the pilot flame is extinguished. Once this error has been rectified, the pilot flame must be re-lit. See paragraph 7.2 Starting up.

• Blocking error due to high limit thermostats You can recognise this status by the fact that the water heater will not start operation, despite the water temperature being lower than you have set with the control thermostat (see 5.5 Control thermostat). This error disappears automatically once the high limit thermostat resets itself, after which the water heater re-starts.

• Lock out error due to the combustion products discharge safety device

This error state has much the same characteristics as a 'Blocking error'. The difference here is that the lock out (push button) for the flue gas thermostat in the draught diverter is activated. See paragraph 5.6 Flue gas thermostat

reset button. After removing the cause, the push button must be pressed to

allow the water heater to automatically re-start.

The cause of the error cannot be seen on the control panel. Please refer to chapter8 Troubleshooting for a detailed overview of error states.

If you find the water heater in a fault state, as an end user you can attempt to re-start the water heater, see paragraph '7.2 Starting up

However, should the error return or become persistent, you should contact your service engineer.

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Error states of the water heater

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7 Starting up and

shutting down

7.1 Introduction Topics covered in this chapter:

• Starting up;

• Shutting down.

Introduction

Figure 7.1 Gas control

7.2 Starting up Start-up the water heater as follows:

1. Fill the water heater. See chapter 4 Filling and draining.

2. Open the manual gas valve. See Figure 4.1 Connection diagrams.

3. Switch on the power to the water heater using the isolator between the water heater and the power supply.

IMD-0195

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7.3 Shutting down You c an :

Starting up and shutting down

4. Begin the ignition procedure by pressing and holding the white button a on the gas control while repeatedly pressing the piezo igniter b until the pilot flame ignites. See Figure 7.1. The pilot flame can be viewed through the inspection window above the burner tray.

Warning

If the pilot flame goes out during the ignition procedure or warm-up cycle, you must wait 5 minutes before repeating the ignition procedure.

5. Keep the white button pressed in for about 30 seconds before carefully releasing it. The pilot flame should now stay lit.

6. Switch the water heater to the 'ON mode' by switching the On/Off-switch on the control panel to the Iposition.

7. Set the desired water temperature using the control thermostat. See paragraph 5.5 Control thermostat.

If there is a heat demand, the heating cycle will run its course. See paragraph

7.4 Heating cycle'.

• Shut the water heater down for brief periods ("OFF mode").

• Isolate the water heater from the power supply.

• Shut the water heater down for a longer period.

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7.3.1 Shut the water heater down for brief periods ("OFF mode")

To shut down the water heater for a brief period, you can set the water heater in "OFF-mode". Activate frost protection by switching the On/Off-switch on the control panel to the 0 position. The pilot flame will remain on.

7.3.2 Isolate the water heater from the power supply

When servicing, the water heater must be electrically isolated. The correct procedure is as follows:

1. Put the water heater in OFF mode by switching the On/Off-switch to the 0 position.

2. Switch off the power to the water heater by switching the isolator between the water heater and the mains power supply to position 0.

3. The pilot flame will remain on, but you can extinguish it if required by pressing the red button c on the gas control. See Figure 7.1.

cCaution

These operating states of "OFF mode" and "Isolated" are advisable only if there is no risk of frost. If frost can be expected, you will need to drain the water heater, see paragraph 7.3.3 Shut the water heater down for a longer

period.

7.3.3 Shut the water heater down for a longer period

Drain the water heater if you are shutting it down for a longer period of time. Proceed as described in paragraph 4.3 Draining the water heater.

7.4 Heating cycle The heating cycle is activated as soon as the measured water temperature

falls below the threshold value (Tset). Tset can be adjusted using the

water)

control thermostat, for example position 3 (60°C).

The heating cycle runs in turn through the following states:

1. HEAT DEMAND;

2. IGNITION;

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Heating cycle

3. RUNNING;

The complete cycle is explained in the example set out below.

1. The control thermostat sensor measures the water temperature (T T

drops below the set temperature (T

water

the control thermostat will close. This will cause the gas control to open.

2. Once the gas control is open, the pilot burner will ignite the gas flow.

3. The water heater is now running. This means that actual heating has started. When the water is up to temperature, the heat demand cuts out. The gas control closes and the burner tray is extinguished (the pilot flame stays lit).

4. The water heater is now said to be in a state of rest and waiting until T once again falls below T

With any subsequent heat demand, the heating cycle will resume from step 1.

set

), there is a heat demand and

set

water

). If

water

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Starting up and shutting down

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8 Troubleshooting

8.1 Introduction This chapter covers the following errors:

General errors

- Gas smell.

- Water leakage.

- Explosive ignition.

- Poor flame profile.

- Power Anode (optional)

• No hot water

• Insufficient hot water.

General errors cannot be displayed on the control panel, but these errors usually do not cause the hot water supply to fail, neither fully nor partially.

If the hot water supply should fail, this is termed an error state. See paragraph

6.1 Error states'.

If the hot water supplied is insufficient, this is usually caused by an incorrect setting or some temporary problem.

The following pages provide troubleshooting tables for each type of error.

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Immediately contact your installer or local gas company.

n Note

Warning

Immediately close the main gas valve.

Warning

Maintenance should only be carried out by a qualified service and maintenance engineer.

8.2 Troubleshooting table for general errors

Table 8 . 1 General errors Page 1 of 2

Symptom Cause Solution Remarks

Gas smell Gas leak

Warning

Do not operate any switches.

Warning

No naked flames.

Warning

Ventilate the room where the water heater is located.

Tighten the threaded connection. If the leak has not been repaired, consult your installer.

Water leakage Leakage from a water

Trace the leak.

connection (threaded).

Leakage from another

water water heater or

Consult the supplier and/or manufacturer.

pipe nearby.

Leakage from the

water heater's hot

the heater has reached the set temperature.

water tank.

Condensation Before drawing off hot (too much) tap water, wait until the water in

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If ignition is not improved, consult your installer.

Set the correct supply pressure and/or burner pressure, see

3.12 Checking the supply pressure and burner pressure.

water heater is located.

If the error cannot be corrected, consult your installer.

'appendix A DR-LP electrical diagram';

1. Check that the water heater is full of water;

2. Check that the Power Anode is properly connected, see

3. Check to see that all connections are properly made;

4. Check all cables for breaks and replace if any are found.

Check the power supply

contact with the

water;

cables;

earthed;

Incorrect supply

pressure and/or burner

pressure.

Contaminated burner Clean the burner. See 9.4.2 Cleaning the burners

Contaminated injector Clean the injector. See 9.4.3 Cleaning the injectors

Inadequate air supply Improve the air supply by better ventilating the room in which the

Warning

Maintenance should only be carried out by a qualified service and maintenance engineer.

Table 8 . 1 General errors Page 2 of 2

Explosive ignition

Symptom Cause Solution Remarks

Poor flame profile

• Anodes not making

red

Power Anode

(optional)

• Indicator lamp is

• Break in one of the

• Anode poorly

No power supply to the

• Indicator lamp is

potentiostat;

off

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If ignition is not rectified, consult your installer

installer.

- Check whether the control thermostat is working.

- Check whether the high-limit thermostat is working.

- Check that the circulation pump (if present) is working.

- Check whether the thermostat may be broken.

- Check whether the thermostat sensor may be broken.

2. Check the voltage across the isolator.

The measured voltage must be 230V AC +15% -10%.

2. Check that gas control opens (clicking of the gas control).

3. Check the gas control wiring.

1. The safety thermostat has cut out correctly:

2. The safety thermostat has cut out without apparent reason:

If the water heater fails to supply any hot water, there are several possible causes.

Consult the table Table 8.2 No hot water.

Warning

Maintenance should only be carried out by a qualified service and maintenance engineer.

8.3 Troubleshooting table 'no hot water'

Table 8.2 No hot water

No power 1. Check that the isolator is ON.

flame LIT)

No ignition (Pilot

Symptom Cause Solution Remarks

Pilot flame OUT Pilot flame blown out 1. Start up the water heater. See paragraph 7.2 Starting up. If the error cannot be resolved or is persistent, contact your

No Gas: 1. Check that the gas valve is open.

The safety thermostat

has cut out

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If the error has not been rectified and no other cause can be found,

isolate the water heater from the power supply, shut off the gas

valve and alert your installer.

heater enough time to heat up the water.

thermostat is cutting in/out. If so, check that the circulation-

and/or top to bottom recirculation pumps are working properly.

1. Reduce the rate of hot water consumption. Allow the water

Hot water supply used

2. If this error occurs regularly, check whether the high-limit

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Set the control thermostat to a higher setting. See paragraph

5.5 Control thermostat.

) too low

set

If the water heater fails to supply any hot water, there are several possible causes.

Consult the table Table 8.3 Insufficient hot water

Warning

Maintenance should only be carried out by a qualified service and maintenance engineer.

8.4 Troubleshooting table 'insufficient hot water'

Table 8.3 Insufficient hot water

setting (T

Symptom Cause Solution Remarks

Insufficient hot water Water temperature

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Warning

Maintenance should only be carried out by a qualified service and maintenance engineer.

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9 Maintenance

9.1 Introduction

Introduction

cCaution

Maintenance may only by carried out by an approved service and maintenance engineer.

At each service, the water heater undergoes maintenance both on the water side and on the gas side. The maintenance should be carried out in the following order.

1. Preparing for maintenance;

2. Water-side maintenance;

3. Gas-side maintenance;

4. Finalising maintenance.

9.2 Preparing for maintenance

9.3 Water-side maintenance

n Note

Before ordering spare parts, take a moment to write down the water heater type and model and the full serial number of the water heater. Only with this information can you be sure to receive the correct spare parts. These details can be found on the rating plate.

To test whether all components are still working properly, you should complete the following steps:

1. Check the supply pressure and burner pressure and adjust these, where necessary. See paragraph 3.12 Checking the supply pressure and burner

pressure. Also check that this is running properly during the warm-up cycle.

See paragraph 7.4 Heating cycle.

2. Check that all components of the flue gas system are properly attached.

3. Test the operation of the expansion valve of the cold water supply arrangement. The water should spurt out.

4. Test the overflow operation of the T&P valve. The water should spurt out.

5. Check the wastewater pipes of the overflow valves and remove any scale deposits that may be present.

6. Drain the water heater. See paragraph 4.3 Draining the water heater.

9.3.1 Introduction

The following steps should be carried out on the water side:

1. Checking the anodes.

2. Descaling and cleaning the heater.

9.3.2 Checking the anodes

Timely replacement of the anodes extends the service life of the water heater. The anodes that are present must be replaced as soon as they are 60% or more used up (take this into consideration when determining the maintenance frequency).

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Maintenance

Take care

The draught diverter and the cover may be hot.

9.3.3 Descaling and cleaning the heater

1. Remove the flue gas thermostat connector from the connector on the unit.

2. Disconnect the draught diverter from the flue gas discharge.

3. Undo the screws on the draught diverter.

4. Remove the draught diverter from the water heater.

5. Undo the screws on the cover on the top of the water heater.

6. Remove the cover from the water heater.

7. Remove the sealing ring from the hot water tank.

8. Loosen the anodes using suitable tools (27 mm A/F).

9. Check the anodes and if necessary, replace them.

10. Now also check the flue baffles. Replace them, if necessary. See paragraph

9.4.4 Checking the flue baffles.

11. Fit a new sealing ring around the edge of the hot water tank and replace the cover.

12. Reconnect the flue gas thermostat connector to the connector on the unit.

n Note

This unit is also appropriate for the use of Power Anodes. These are available as an accessory and can be ordered separately. Please check your Power Anode instructions for correct use or consult your installer.

Scale and lime buildup prevent effective conduction of the heat to the water. Periodic cleaning and descaling prevents buildup of these deposits. This increases the service life of the appliance, and also improves the heating process.

Take the rate of scale formation into account when deciding on maintenance frequency. Scale formation depends on the local water composition, the water consumption and the water temperature setting. A water temperature setting of maximum 60

To guarantee a good, watertight seal around the cleaning opening, the gasket , O-ring g, spring washers, bolts and if necessary, the lid c should be replaced with new parts before reassembly. See Figure 9.1. A special set is obtainable from State for this purpose.

To simplify descaling and cleaning of the tank, the appliance is equipped with two cleaning openings.

c is recommended for prevention of excessive scale buildup.

Figure 9.1 Cleaning opening

1. Remove the cover plate a on the outer jacket. See Figure 9.1.

2. Carefully remove the insulation b and set it to one side. This will be needed

again later.

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Gas-side maintenance

3. Undo the bolts.

4. Remove the lid, the gasket and the O-ring.

5. Inspect the tank and remove the loose scale deposits and contamination.

6. If the scale cannot be removed by hand, then the appliance will need to be descaled using a suitable cleaner.

7. Close the cleaning opening. To avoid damage to the tank, the bolts that fasten the lid should be tightened with a torque no greater than 50 Nm. Use

suitable tools for this. To properly seal the cleaning opening, we recommend tightening the bolts in the sequence shown in Figure 9.2.

Figure 9.2 Bolt tightening sequence

9.4 Gas-side maintenance

Take care

The burners may be hot.

9.4.1 Introduction

On the gas side the following steps should be carried out:

1. Cleaning the burners.

2. Cleaning the injectors.

3. Checking the flue baffles.

9.4.2 Cleaning the burners

1. Detach the burners.

2. Carefully remove any contaimation present on the burners.

3. Re-attach the burners.

9.4.3 Cleaning the injectors

1. Detach the injectors.

2. Remove any contamination present in the injectors.

3. Re-attach the injectors.

9.4.4 Checking the flue baffles

Take care

The flue baffles may be hot.

9.5 Finalising maintenance

1. Complete steps 1 to 7 from paragraph 9.3.2 Checking the anodes.

2. Remove the flue baffles from the water heater.

3. Check the flue baffles for rust and remove any rust which is present.

4. Check the flue baffles for wear and replace any worn flue baffles.

5. Fit a new sealing ring around the edge of the hot water tank and replace the cover.

6. Reconnect the flue gas thermostat connector to the connector on the unit.

To finalise the maintenance carry out the following steps:

1. Fill the water heater. See paragraph 4.2 Filling the water heater.

2. Re-start the water heater. See 7.2 Starting up.

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Maintenance

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A DR-LP electrical

diagram

230V AC 50Hz

L N

L L N

123456789 1210 11

4J4 4

LL3NL

4 1

1 =

2 =

3 =

4 =

5 =

TERMINAL BLOCK CONNECTIONS:

A Earth

NNeutral

Phase input to week timer

Phase input to thermal non-return safety device

Phase input to main gas valve

brown

blue

yellow/green

black

white (flat cable)

Figure A.1 SCT electrical diagram

COMPONENTS:

A On/off switch B Con trol thermostat C High-limit thermostat D Safety thermostat E Thermal non-return safety device F Gas control G Eye terminal (for earthing to the Jacket)

OPTIONAL COMPONENTS:

H Main power switch J Week timer

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DR-LP electrical diagram

60 Instruction manual DR-LP