The Keston Condensing Boiler

Wherever You Want Your Boiler Sited.

Because Keston boilers are room sealed and have a unique and versatile flue/air intake system, your boiler can be situated practically anywhere and in the most convenient position. The flue/air intake is small diameter standard muPVC plastic kitchen wastepipe measuring just 40mm (l'/2") for the domestic range which can be extended up to 10 metres in length, and 50mm (2") for the Keston 130 and Keston 170 commercial models which can be extended up to 15 metres in length from the appliance.

With Keston boilers installation costs and valuable space can be saved as well as saving labour, money on fuel bills and the environment.

With conventional boilers approximately one third of the heat generated can be lost up the chimney. With a Keston Condensing Boiler this heat is returned to the central heating. The Keston Condensing Boiler will operate at efficiencies of up to 99% which cuts carbon dioxide emissions, a major contributor to the Greenhouse effect, and consequently fuel bills. In addition, the patented combustion technology burns so cleanly that NOx emissions, a major cause of acid rain, can be reduced to less than 5ppm (parts per million), well below even the most stringent environmental requirements and possibly the lowest of any boiler available today.

Make Your Contribution Towards The Environment.

Although gas is the cleanest of commercially available fuels, heating and hot water is probably one of the most expensive annual bills on your pocket and on the environment. By installing a Keston Condensing Boiler you could save over 30% on heating costs, at the same time making your contribution towards the environment by keeping the air we breath as clean as possible and conserving valuable resources for future generations.

This in conjunction with the flueing flexibility and low maintenance are the essential reasons for installing a Keston Condensing Boiler.

The Keston range of condensing boilers provides outstanding benefits to both the installer and their customers, today and for the future. Super high efficiency and reliable heating systems, combined with ultra low NOx combustion means very low running costs and virtually no atmospheric pollution. All this in a package which is simplicity itself to install, maintain and operate.

How does it work?

The Keston is a revolutionary concept covered by world patents. The design provides high efficiency, with a single pass heat exchanger, and clean combustion without the complications of other condensing boilers. Air is drawn into the unit via a 40mm* plastic pipe and an in-built filter. A measured amount of gas is injected into the air stream and the mixture is passed through a highly turbulent blower. This blower forces the mixture of gas and air into a patented micro-mesh burner which burns with a tight blue flame, after being Ignited by a spark electrode. There is no pilot or thermocouple in the appliance.

 

The hot combustion gases pass down the centre of a tightly coiled steel tube carrying the central heating water. When the combustion gases emerge from the base of the water coil the temperature is reduced to around 5°C above the return water temperature. The cooled gases are
then forced out of the heat exchanger into the 40mm* plastic pipe where they are discharged to the atmosphere.

The Keston incorporates a patented single pass heat exchanger providing high efficiency without the normal complex double heat exchanger system of other condensing
boilers. Its compact construction of high grade super alloy stainless steel ensures long life and carries a guarantee against leakage. *50mm for the Keston 130 and Keston 170.

Condensate "Pluming" Taken Care Of.

All condensing boilers will generate 'pluming' which appears as steam from the flue terminal. On other condensing units this pluming can drift across nearby windows causing annoyance and possible condensing on the window glass or frame. With the Keston Condensing Boiler it is easy to reach a location well away from windows or openings. In addition, the high speed of the flue gases causes the plume to be blown far away from the terminal and well clear of the building.

No Printed Circuit Boards

The simple concept of the Keston means that no printed circuit boards are required (apart from the
sealed spark ignition unit). Hence, electrical wiring of the unit is simplicity itself.

The Keston Condensing Boiler Schematic.

1. Heating Return 2. Water Return Thermostat 3. Downstream PTN 4. Spark Electrode 5. Mirco-mesh Burner 6. Automatic Air Vent 7. Flow Overheat Thermostat 8. Heating Flow 9. Flue 10. Air/Gas Flexible Hose 11. Air Inlet Filter 12. Flexible Air Intake Hose 13. Ignition Control Box 14. Low Gas Pressure Switch 15. Gas Control Valve 16. Gas Inlet 17. Air Pressure Switch 18. Combustion Blower 19. Condensate Trap 20. Flue Overheat Thermostat 21. Heat Exchanger 22. Flow High Limit Thermostat 23. Low Water Pressure Switch 24. Combustion Test Point 25. Flue PTN * Heating return exits base of cabinet on Keston 130 and Keston 170 models.