Specifications
5.3 DESIGN FEATURES
5.3.1 OUTER BODY
The outer body containing the primary fluid is made of STW 22 steel.
5.3.2 TANK-IN-TANK TYPE EXCHANGER ACCUMULATOR
The ring-shaped inner tank with its large heating surface for producing
domestic hot water is built of Chrome/Nickel 18/10 stainless steel. It is
corrugated over its full height by an exclusive production process and
entirely argon arc welded by the TIG (Tungsten Inert Gas) method.
5.3.3 COMBUSTION GAS CIRCUIT
The combustion gas circuit is protected by cold galvanisation. The
combustion gas circuit comprises:
5.3.3.1 Flue pipes
Depending on output, DELTA Classic models contain 4 or 8 steel
flue pipes with an internal diameter of 64 mm. Each pipe is fitted
with a baffle of special steel designed to improve heat exchange
and reduce flue gas temperature.
5.3.3.2 Combustion chamber
The combustion chamber on DELTA Classic models is water
cooled.
5.3.4 INSULATION
The boiler body is fully insulated by rigid polyurethane foam with a high
thermal insulation coefficient, sprayed on without the use of CFCs.
5.3.5 JACKET
The boiler is covered by a steel jacket which has been scoured and
phosphated before being stove enamelled at 220° C.
5.3.6 BURNER
DELTA Classic boilers are fitted with an atmospheric burner with elec-
tric ignition.
IMPORTANT
When starting the burner for the first time and when
servicing it, refer to the technical instructions supplied
with it.
5.3.7 CONTROL PANEL
(Fig. 15)
1 - Thermostat adjustable between 60 and 90° C
2 - On/off switch
3 - Summer/winter selector
4 - Thermometer
5 - Knockout for (optional) controller.
5 DESCRIPTION
Fig. 15: Boiler structure
12
1
15
2
4
3
5
14
6
19
8
11
9
13
7
20
16
18
17
7
10
Fig. 16: Control panel
241 3 5
9
1. Inner ring-shaped domestic hot water tank
2. External body containing central heating circuit
3. Insulation
4. Jacket
5. Flue pipes
6. Baffles
7. Control thermostat 60/90° C
8. Lower heating return
9. Combustion chamber
10. Burner chamber plate
11. Boiler drain
12. Upper heating flow and return
13. Chimney connection
14. Control panel
15. Domestic hot water outlet
16. Domestic cold water inlet
17. Cut-off thermostat 95° C / Thermometer
18. Manually reset safety thermostat 103° C
19. Gas burner
20. Burner chamber disk.