Coffeemar
G-250
//
Coffee
MNP116M01GBV00
Date: 09/04/2013 Rev. 1
PAGE 20 OF 95
0.7 to 0.9 MPa (the machine is factory set to achieve this pressure level for a 7 g (0,0154
lb) puck).
Note:
The assembly brews at constant minimum pressure above 0.7 MPa from the first
drop to the last.
Boiler
This is the tank that stores the hot water supplied to the coffee assembly and to the
soluble product mixing beaters. This tank is made of brass with an approximate capacity
of 330 cc. The water is heated using an 1.100 W, 220 V (110-125V) heating element.
Fig. 22
BOILER
A.
Upper body
B.
Lower body
C.
Water inlet
D.
Klixon
E.
1100 W heating element
F.
3/2-way solenoid valve for beans
G.
3/2-way solenoid valve for solubles
H.
Espresso outlet coupling
I.
H. Soluble outlet coupling
J.
Temperature control (NTC)
K.
Hoop
The water dose is determined by two 3/2-way solenoid valves, one for the beater
assembly and the other for the coffee assembly.
The boiler consists of a brass body with stainless steel inserts in the solenoid valve seats
to prevent scale accumulation in the more sensitive areas with a 220 V (110-125V)
power supply. The solenoid used to supply water to the espresso assembly enables the
water left in the Teflon tube after brewing to flow back after the valve closes. This outlet
communicates with the waste bin. The other outlet is directly connected to the coffee
assembly.
Dosage of the water of the various products available is achieved by controlling the
amount of water using a volume counter located behind the air-break. This allows for a
very accurate control of doses, while ensuring that the pressure boiler is always full of
water, as the same amount of water that goes out comes in.
On the side of the cover there is a sensor for controlling water temperature. This sensor
is programmed to keep water boiler temperature at 90 °C (194 °F), although this
temperature is programmable. The two covers are kept air-tight with a silicone O-ring.
Should the temperature sensor fail, the boiler has the following control systems:
