Dimplex SCx175sd, SCx215sd, SCx255sd, SCx175si, SCx305sd Installation And Operation Manual

SOLAR

UNVENTED WATER HEATERS

Installation and Operation Manual

Important -This Manual Should Be Left With The Cylinder After Installation

2

Contents

Section Page

1 Introduction 3
2 Technical specifications 3
3 Check list 5
4 General requirements 5

5 Primary circuit installation 6
6 Secondary circuit installation 6
7 Discharge arrangement 8
8 Electrical installation 10
9 Filling and commissioning 11
10 Servicing and maintenance 12
11 Fault finding 13
12 User instructions 13
13 Warranty 14
14 Part Numbers 15
15 Service Record 16

3

1. Introduction

The SCX Solar cylinder is a high quality stainless steel unvented cylinder designed for use with all
solar systems to provide hot water from a cold mains water supply of between 3bar and 12bar.
Reduced performance is available at lower pressures but the units are not suitable for pressures
lower than 1.5bar and flow rate of less than 20 litres per minute. The indirect heat exchange surfaces
are designed to provide a rapid heat up time. The unit comes complete with all the necessary safety
equipment to comply with legislation governing the installation of such systems.

1.1 Cylinder Suitability:

The

SCX Solar cylinder should only be used as part of a solar installation and configured as shown in

figure 1.2. Additional safety devices may be required if the cylinder is operated with other heat sources.

2. Technical Specifications

Model Number SCx175sd SCx215sd SCx255sd SCx305sd SCx175si SCx215si SCx255si SCx305si

Storage capacity (litres)

175 215 255 305 175 215 255 305

Cylinder diameter (mm)

574 574 574 574 574 574 574 574

Aux Water volume (l)

90 130 170 215 105 140 180 230

Overall height (mm)

1300 1542 1809 2085 1300 1542 1809 2085

T&P Valve (mm)

1080 1322 1589 1865 1080 1322 1589 1865

Lower Immersion (mm)

593 593 593 593 593 593 593 593

Top Immersion (mm)

908 1150 1417 1693 - - - -

Solar Flow (mm)

542 542 542 542 542 542 542 542

Solar Return (mm)

380 380 380 380 380 380 380 380

Cold Inlet (mm)

300 300 300 300 300 300 300 300

solar Coil size sqm

1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1

Aux Coil size sqm

- - - - 0.75 0.75 0.75 0.75

Auxiliary Flow (mm)

- - - - 904 904 904 904

Auxiliary Re turn (mm)

- - - - 742 742 742 742

Weight when full (kg)

219 267 314 374 223 271 318 378

Heat-up time* (m)

20 24 28.5 34 18 21.5 25 30

Re-heat time* (m)

14 17 20 24 13 16 19 22

Heat Loss in 24hr (kw)

1.78 2.19 2.31 2.51 1.78 2.19 2.31 2.51

Secondary Return •• ••••• •
Primary flow/return connections (mm)

22 22 22 22 22 22 22 22

Cold feed/hot draw off connections (mm)

22 22 22 22 22 22 22 22

Maximum water supply pressure (bar)

12 12 12 12 12 12 12 12

System operating pressure (pre-set) (bar)

33 333333

Expansion vessel charge pressure (bar)

33 333333

Maximum primary working pressure (bar)

33 333333

Package includes:

Expansion vessel ltr 18 18 25 25 18 18 25 25
Inlet Valve Group (pressure reducing valve, non
return valve, 6 bar expansion relief valve, line

•• ••••• •

T/P valve 7bar 90degC (factory fitted) •

•••

•

••

•

15mm to 22mm Tundish •

•••

•

••

•

22mm motorised valve −

−−−

•

••

•

Control/limit thermostat box

•

•••

•

••

•

Immersion heater 2

222

1

11

1

2.1 Heat-up & Reheat Times*

*Heat-up and reheat times are for a guide only and are based on a primary flow temperature of 60oC
and heating water from 15

o

C to 60oC. The immersion of the cylinder or external boiler must be used

to raise the temperature to 60

o

C from the maximum temperature achieved at any time by the solar
system,.
Reheat times are those to heat 70% of the cylinder from cold.

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2.2 Connection

2.2.1 SOLAR Indirect

2.2.2 Single Coil Direct Electric

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3. Check List

• Cylinder

• 18 litre Expansion Vessel

• 25litre Expansion vessel

• Expansion vessel bracket

• 22mm Inlet group (Pressure reducing valve, Expansion relief valve, non-return valve, line

strainer

• ½” T/P valve, 7bar/90

o

C factory fitted

• 15/22mm Tundish

• 2 x Twin Thermostat (Indirect cylinders only)

• Immersion heater

• 1x 22mm two-port Motorised Valve (Indirect cylinders only)

4. General requirements

4.1. The solar domestic hot water cylinder MUST be installed by a competent person in accordance

with section G3 of the current Building Regulations and any other regulations in force at the time of
installation.

4.2. It is essential to read and understand these instructions, unpack and familiarise yourself with the
equipment before commencing the installation. Failure to observe these installation instructions could
invalidate the warranty.

4.3. Water supply – The water supply to the cylinder should be potable water direct from a public
mains water supply with any water treatment equipment functioning correctly.

The unit, should be fed via a 22mm diameter supply pipe direct from the mains water entry point to
the property. It requires a supply pressure of 1.5bar with a flow rate of at least 20litres per minute as a
minimum for it to function, but flow from the outlets will be low if several outlets are used
simultaneously. Correct performance is achieved with supplies between 3bar and 12bar. The cylinder
control equipment is factory set to limit the system operating pressure to 3bar. The maximum supply
pressure into the pressure-reducing valve is 12bar.

4.4. Taps and fittings - All taps and fittings incorporated in the unvented system should have a rated
operating pressure of 7bar or above.

4.5. Location – The cylinder is designed to be floor standing, vertically mounted, indoors, in a frost­free environment. When choosing a suitable location for the cylinder, consideration should be given to
the routing of the discharge pipe to a convenient safe and visible point and also the location of the
solar system.

The cylinder may stand on any flat and level surface, provided that it is sufficiently robust to support
the weight of the cylinder when full of water. (See Technical specifications for weights).

The position of the cylinder should be such that easy access is provided for servicing the controls and
replacing the immersion heater should the need arise.

Pipe runs should be made as short as possible and lagged according to current building
recommendations to prevent heat loss.

4.6. Storage and handling – If the cylinder is not being installed immediately, it should remain in its
carton with all pipe end protective caps in place to prevent damage.