Solar Heating with Underfloor Heating TX 113

The SunCylinder System

Next Generation Heating

60 years ago, the concept of circulating high temperature water from a boiler through radiators fitted in each room was still new. Since then, it has become the standard way of heating most buildings in the UK. The consequence is that more than 99% of the buildings in the UK are now dependent for their heating on a central boiler which uses a fossil-fuel. Yet we all know that these fuels are running out and becoming increasingly more expensive. Government figures record that 4 million UK households were already in “fuel poverty” in 2009. Despite this, we continue to fit new buildings with heating systems that are dependent on high temperature fossil-fuel boilers. “What is the alternative?” The recent big change has been the development of a new generation of highperformance underfloor heating products, for both retrofit and new build, which are able to provide very comfortable and effective heating while using water which is only 35-45OC. Along with this, a new generation of solar thermal cylinders has been developed that can more effectively store and use the energy collected from solar thermal even on a winter’s day.

The ‘Brains’ of the SunCylinder system enables solar heated water to be used more effectively

Timóleon low temperature underfloor heating systems.

These two developments - low temperature underfloor heating combined with a clever storage and control system - mean that over 40% of the building’s heat load can be satisfied by energy collected from the sun. Lower bills, faster payback and less reliance on fossil fuels.

Timóleon underfloor heating systems are designed to use low water temperatures, low enough to use the heat collected by a solar thermal panel. To ensure good performance at low water temperatures it is crucial that there is a conductive pathway that transfers heat quickly from the pipe to the floor surface. If there is a break in the conductive pathway i.e. an air gap, then the efficiency of this energy transfer is greatly reduced. To overcome this inefficiency the water used in the heating system needs to be much hotter to produce an effective heat output. In independent tests at BSRIA, systems that have an air gap between the pipe and floor deck are up to 60% less efficient at transferring energy than Timóleon systems. This means they have to use water at least 10 oC hotter to produce the same heat output.

The Toron Flooring System has been designed to work at low water temperatures.

Simply, solar thermal panels during the winter have far less incident solar energy than in the summer. In these conditions the solar panel can still collect a reasonable amount of energy but at a low water temperature which isn’t useable by most heating systems such as radiators.

Peak solar energy received throughout the year

How to use solar energy in our heating systems.

Solar thermal can be used to contribute to the heating system. There are four dimensions that are crucial to making this work:

Heat emitters designed to work at low water temperatures. A control system that recognises when the stored low temperature water can be used for the heating system. A way of storing the water to make best use of it for both the heating and hot water. An efficient and correctly sized solar array.

Timoleon underfloor heating systems are designed to be effective when using low water temperatures. This means that the energy collected and stored by the solar thermal panels during the winter, autumn and spring can be used without the need to automatically run the boiler or heat pump. The SunCylinder system provides the necessary storage and control to make this work.

The SunCylinder System

Why don’t we normally use heat collected from Solar Thermal in our heating systems?

The SunCylinder System

Solar heating and the SunCylinder system.

The SunCylinder system works by making full use of energy collected by the solar thermal panels even when this is stored at relatively low water temperatures. The SunCylinder system has a unique control that calculates the required heating system water temperature, if this required temperature is lower than the water in the cylinder then it will use this stored energy before firing the boiler. For example when the weather is very cold, say -3˚C, then the underfloor heating system may need water at 45˚C but when the outside temperature is higher, around 8˚C, the required water temperature will be about 35˚C. If the water in the cylinder is above 35˚C the control system uses the heat stored in the cylinder rather than activate the boiler or heat pump. As soon as the water temperature in the cylinder drops to an unusable level then the boiler or heat pump are activated. This method of control makes better use of the solar thermal energy. A conventional heating system will fire a boiler when there is demand heating up the thermal store to 60˚C or 70˚C regardless of what temperature is needed by the heating system. When water is stored at this high temperature it is impossible for the solar thermal to be able to store any heat collected from the panels.

Solar Thermal sized for SunCylinder, at least 6m2

All in one intelligent control system

Prefabricated jig with pump & mixing valve

3 coil hot water cylinder system Timóleon low temperature underfloor heating

Alternatively, some systems use a three coil thermal store for heating and hot water. However, on demand, the thermal store will have to heat the stored water to a fixed temperature, usually 65˚C or 70˚C. The use of the solar thermal during the spring, autumn and winter becomes limited as storing water at high temperature makes it impossible for the solar thermal to contribute heat collected at low temperature. Compare this to the SunCylinder system. The SunCylinder is designed so the solar thermal can be used for heating not just hot water. The SunCylinder system is designed to contribute up to 40% of the heating load for the year. As the home’s heating load is 75% of the total load then the SunCylinder system can contribute 30% of the home required energy PLUS some of the domestic hot water demand especially through the summer months. A solar thermal system using SunCylinder has a much faster payback as a result, between 6 and 15 years depending on the type of fuel, the solar thermal input and how the heating system is used.

Doubles the usable energy collected from solar.* *Dependent on the solar thermal input, heating system design and control.

S av

ing

Solar Thermal using a convention twin coil cylinder

JUL

AUG

SEP

OCT

Hot water from solar

NOV

DEC

JAN

FEB

MAR

APR

MAY

JUN

FEB

MAR

APR

MAY

JUN

Total House Load

AUG

SEP

OCT

NOV

DEC

JAN

S

JUL

in av

g

Solar Thermal Using SunCylinder

Hot water from solar

Heating from solar

Total House Load

The SunCylinder System

What makes our system different?

A standard twin coil solar cylinder is expected to provide 60% of the hot water load throughout the year. The hot water load is 25% of the home’s energy load therefore a twin coil cylinder provides 15% of the home’s energy use.

The SunCylinder System

What is the SunCylinder system? A unique patented hot water cylinder design is used in conjunction with a control system. The cylinder has two input coils, one coil for solar thermal and a second coil for the auxiliary heat source, this coil is sized so either a boiler or heat pump can be used. The third output coil supplies the Timóleon underfloor heating system. The cylinder has the same footprint as a conventional cylinder with all the coil and sensor connections located conveniently on one side.

The ‘Brains’ of the SunCylinder system

The control system uses a pre-assembled “jig” for simple onsite installation, this includes the necessary valves and circulator. The electronics are contained within the control box and provides an easy way to set up and commission the system as well as providing connection for the sensors and valves.

Halves the payback time on solar compared to using a thermal store.* *Dependent on the type of fuel used, the solar thermal input, the heating system design and how the heating system is used.

382 litre with boiler coil

510 litre with boiler coil

382 litre with heat pump coil

510 litre with heat pump coil

Storage Capacity

382 litres

510 litres

382 litres

510 litres

Overall Diameter

580mm

663mm

580mm

663mm

Overall Diameter incl. Immersion heaters

642mm

725mm

642mm

725mm

Overal height with expansion vessel on cold feed supply

2100mm

2057mm

2100mm

2057mm

Weight when full

440kg

570kg

440kg

570kg

Primary flow/ retrun connections

22mm

22mm

22mm

22mm

Primary flow/ return connections

28mm

28mm

28mm

28mm

Solar coil area

2.0m2

2.0m2

2.0m2

2.0m2

UFH output coil area

2.0m2

2.0m2

2.0m2

2.0m2

Boiler coil

Boiler coil

Heat Pump coil

Heat Pump coil

1.2m2

1.2m2

3.0m2

3.0m2

35 litre

80 litre

35 litre

80 litre

Description

Auxillary heating coil area Expansion Vessel Size

The SunCylinder hot water cylinder

• •

The SunCylinder System

PATENTED 3-COIL CYLINDER Either 382 or 510 litre cylinder Full Unvented Kit for the cylinder including:

T&P Valve

PRV

Sensor Pockets

Potable Water Expansion Vessel

2no. Immersion Heaters

High temperature 2 port valve for solar thermal shut off

CONTROL BOX •

Weather Compensator & DHW Programmer

Cylinder Sensor

Mixed Water Temperature Sensor

Delta “T” Sensor DHW Temperature Sensor

External Air Temperature Sensor

PRE-ASSEMBLED JIG

3 Port Blending Valve

Electric Head

15 /50 Circulator

22mm Zone Valve

How the SunCylinder system works

1

9

3

2 8

4

5 7 6

Low temperature Underfloor Heating

1

Hot DHW Supply

4

Auxillary Heating input coil

7

Control system & pre-assembled jig

2

Solar Control

5

Solar thermal input coil

8

Boiler or heat pump

3

Low temperature UFH output coil

6

Cold water feed

9

Axios Manifold

Questions? Call the project team.

01392 36 36 05

Timóleon Unit 18 Apple Lane Sidmouth Road Exeter Devon EX2 5GL T F E W

01392 363605 01392 364871 [email protected] www.timoleon.co.uk