Gabarron CM15 Installation instructions and user manual - page 18
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7.2 OVERHEAT LOCK-OUT & RE-SETTING
Central heating overheat.
If the boiler detects a overheat condition of 100ºC (80ºC if adapted floor heating ) in the central heating circuit a safety
thermal limit switch will operate and switch the boiler off disabling all functions including DHW production.
The cause of the overheat should be investigated.
The safety limit switch is on the left underside of the boiler and will require re-setting manually by following the
procedure shown:
Unscrew & remove the black cap and push the
small pin behind it until you hear a click.
The limiter will not re-set until the
temperature in the heating header drops below
100°C or 80°C if the boiler is adapted for
radiant floor heating.
Domestic Hot Water overheat.
As with the heating circuit a second thermal limit switch, situated on the right underside of the boiler, will operate if a
overheat condition (80ºC) is detected in the DHW circuit and switch the boiler off disabling all functions including
central heating.
The cause should be investigated and the above procedure followed to re-set the DHW limit switch.
7.3 HEATING SYSTEM FLOW SWITCH – E3 ERROR & SYSTEM BY-PASS REQUIREMENTS
If the error E3 appears on the display, the flow switch has detected insufficient water flow in the heating circuit and heat
production is disabled to protect the boiler from overheating.
The possible causes for this condition are:
- Insufficient water pressure in the heating system requiring re-filling to 1.5bar
- Pump not circulating or seized. Check as shown (Sect 5.3)
- Blockage in heating circuit from debris or a foreign object in the boiler or pipe-work.
- Insufficient flow rate caused by restrictions such as insufficient size pipe-work, too many bends or isolation valves with
restricted bore.
- Closed radiator valves (Thermostatic). In this situation it is essential the required minimum flow rate of 7 L per minute
is maintained through the boiler during all conditions. It may be sufficient to maintain one radiator with permanently
open valves however the guidance under current Building Regulations relating to the conservation of energy
recommends the fitting of an automatic by-pass valve. This type of valve modulates open when necessary to ensure that
the appropriate minimum flow rate is maintained through the boiler, at all other times it is closed thus preventing
unnecessary and wasteful circulation through the bypass and the boiler.
7.4 CHECKING RATED HEAT OUTPUT
It is possible to check the actual heat power output configuration that is set on the boiler and also the modulated
operating output at that moment.
Press the
button for three seconds.
The heating display will show
followed by the temperature value of the return probe of the heating circuit.
On pushing
button the display will show
followed by the value of the limited maximum output according
to the tables (see 5.1).
On pushing
button again the display will show
followed by the actual modulated output power at that
moment.
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