SP-MAN-INSTALL-01
Revision 2 21-12-21
4.0
How a Condensing Appliance Works
During the combustion process, hydrogen and oxygen combine to produce heat and water vapour. The water vapour produced is in the
form of superheated steam in the heat exchanger. This superheated steam contains sensible heat (available heat) and latent heat (heat
locked up in the flue gas). A conventional boiler cannot recover any of the latent heat and this energy is lost to the atmosphere through
the flue. The EOGB Sapphire condensing boiler is designed to recover the latent heat normally lost by a conventional boiler. It does this by
cooling the flue gases to below 90°C, thus extracting more sensible heat and some of the latent heat. This is achieved by cooling the flue
gases to their dew point (approximately 55°C).
To ensure maximum efficiency, the boiler return temperature should be 55°C or less, this will enable the latent heat to be condensed out
of the flue gases.
To achieve maximum performance from the EOGB Sapphire boiler, it is recommended that the heating system is designed so that a tem-
perature differential of 20°C between the flow and return is maintained. The use of modulating circulating pumps (now widely available)
and effective control systems are essential for optimum fuel efficiency savings and the limitation of unnecessary emissions to atmosphere.
4.1
Boiler Description
The EOGB Sapphire Modulating liquid fuel boiler have been designed for use with a fully pumped central heating system with indirect
domestic hot water cylinder.
They are not suitable for use with either a direct cylinder or a ‘primatic’ cylinder or gravity hot water
.
The boilers are suitable for use on open vented or sealed central heating systems.
The EOGB Sapphire boilers are supplied with the control panel and burner factory fitted.
4.2
Flue Options
EOGB advises that EOGB approved balanced flues are to be used with the EOGB Sapphire boiler.
Please see
separate supplied flue option manual
for more information on flues
4.3
Appliance Components
All appliance are pre-set for use with the intended specified fuel and are supplied to accept a one pipe fuel supply system as standard.
Please note that the appliance is supplied with a 2 pipe loop system in which a single pipe feed will connect to and if required can be
converted to accept a two pipe fuel supply system either by a de-aerator or supply back to the fuel tank.
The appliance is fitted with a primary & secondary manual reset overheat thermostat (which allows it to be used on a sealed central
heating system) which will automatically switch off the appliance if it exceeds a pre-set temperature of 95°C ± 3°C for the primary over-
heat thermostat & 110°C ± 3°C for the secondary overheat thermostat.
The appliance control panel is fitted with an ON/OFF switch and LCD display. The temperature of the water leaving the appliance to heat
the radiators and hot water cylinder is automatically controlled and will require to be pre-set to satisfy the system requirements by an
approved Sapphire Service Engineer
6
WARNING
WARNING
Boiler Introduction
