FAULT FINDING

75ELECTRONIC CONTROL/IGNITION P.C.B. OPTICAL INFORMATION

The electronic control/ignition p.c.b. is provided with three lamps (L.E.D. indicators) A, that give optical information during the normal operation of the boiler or for service and fault fiinding purpose.

Normal operation

The green lamp on the left is directly visible on the control panel fascia and it gives information during the normal operation of the boiler. The other two lamps are normally switched off.

The following table gives the relationship between the visible lamp indication and its meaning.

Boiler in stand--- by condition. (function control in position).

Anti--- freeze system active. A short pulse every 4 seconds

Boiler ON condition

 

(function control in

or

position)

 

1 second ON 1 second OFF

The following table gives a summary of the relationship between each of the possible lamp combinations and their meaning.

Normally operating boiler

C.h. operation

D.h.w. operation

Frost protect operation

D.h.w. operation

Excessive temperature on primary circuit

Faulty c.h. temperature probe NTC

Faulty d.h.w temperature probe NTC

Faulty flue temperature probe NTC

Faulty primary circuit

(no water or absence of flow)

Faulty air pressure switch

Lack of burner ignition (no ignition signal from the full seqence ignition device)

Overheat thermostat lock out

Flue temperature probe NTC lock out

Lack of power supply or fauly electronic control p.c.b. *

Faulty Electronic control/ignition p.c.b.. *

Lamp

Lamp

Flashing lamp, alone

Flashing lamp,

OFF

ON

or simultaneously

alternate with

 

 

with an other lamp.

another lamp.

*These conditions are normal only for a short time when the power supply is applied to the boiler.

If permanent they indicate a faulty p.c.b.

FAULT FINDING

76DIVERTER VALVE ACTUATOR SPINDLE POSITION

To remove the diverter valve actuator refer to frame 69.

The following illustrations indicate the relationship between the electric command coming from the main control p.c.b. and the position of the brass spindle when the boiler operates in either DHW mode or CH mode.

In both figures the relationship between the position of the actuator and the resistance of the motor windings (the motor must be disconnected from the wiring) is also given.

Spindle visible

3 2

1

 

bk

 

bu

 

bn

 

 

 

 

 

 

CH mode

Open circuit

9,4 Kohm

Spindle fully

DHW mode

retracted

3 2

1

9,4 Kohm

Open circuit

 

bk

 

bu

 

bn

 

 

 

 

 

 

0 V

230V

 

 

bn = brown

V

 

bu = blue

230

0 V

bk = black

mini HE --- Installation & Servicing

51

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Mamiya C32, C28, C24 manual Normal operation, Off

C28, C24, C32 specifications

The Mamiya C series is celebrated among photography enthusiasts for its unique twin-lens reflex (TLR) design, offering both a classic aesthetic and innovative features that set it apart in the world of medium format cameras. The C32, C24, and C28 models represent a range of technology and design advancements that cater to various shooting needs.

The Mamiya C32, introduced in the early 1970s, is renowned for its precision engineering and versatility. This model features interchangeable lenses, allowing photographers to switch between different focal lengths for creative flexibility. The camera supports 120 and 220 film formats, enabling higher film capacities for extended shooting sessions. An essential feature of the C32 is its built-in light meter, which enhances exposure accuracy by providing real-time readings. The camera's bright waist-level finder offers excellent viewing comfort and composition aid, attracting those who appreciate a more hands-on shooting experience.

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