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The BAXI Stainless Steel Solar water heaters have a storage vessel manufactured from duplex stainless steel. The
heat exchanger coil and connections are manufactured from grade 316L stainless steel. The vessel is insulated with
HCFC/CFC free expanded polyurethane foam. The outer casing is manufactured from a combination of pre-painted
steel and polypropylene moulded end caps and terminal housings.
Working Principle
The inlet of the storage vessel is connected to the cold water mains supply to the property; the outlet is connected to
the various hot water fittings in the property.
The solar heat exchanger coil (lower coil) of the vessel is connected to the primary heating circuit of the solar thermal
system. When the control thermostat of the vessel is calling for heat and there is sufficient solar energy, hot water
from the solar collectors flows through the solar heat exchanger coil raising the temperature of the stored water. When
the pre-set storage temperature is reached the solar control thermostat will interrupt the heating flow from the solar
collectors.
Auxiliary heating can be provided by a conventional heat source (eg. Boiler) connected to the upper coil of the twin
coil version. The boiler primary circuit must incorporate its own temperature and safety controls. In the case of the
single coil unit, auxiliary heating can be provided by fitting an electric immersion heater (available as an accessory).
When a hot water fitting is opened hot water from the vessel will flow to the fitting under the pressure of the incoming
cold water supply. Mixing of the cold water with the hot stored water is minimised by a baffle inside the vessel.
The vessel is kept at a hot temperature by the efficient thermal insulation.
Diagram 1 – Connections
1
1
2
2
5
6
9
9
10
10
7
8
7
8
3
4
GENERAL CHARACTERISTICS
1
Sanitary water outlet
2
Secondary circulation
3
Auxiliary coil primary flow
4
Auxiliary coil primary return
5
Auxiliary heat source controls housing
6
Immersion heater connection
7
Solar coil primary flow
8
Solar coil primary return
9
Sanitary water inlet
10
Solar sensor pocket and controls housing
307625_Baxi_Install Guide_AW:Dual cover follow on
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