Heating system controls
CONTROLS GENERAL
1.1The controls fitted to the system will provide two functions:
—To control the comfort level in the house.
—To maintain safety in the event of misuse or mechanical failure.
COMFORT CONTROLS
1.2This primarily consists of a time clock wired into the pump. The pump is switched on when heat is required and when it is not, the pump is switched off.
The time clock, when combined with a room thermostat and or thermostatic radiator valves, enhances the comfort levels in the house.
Some room thermostats combine the function with the time clock and can be programmed to reduce the room temperature rather than turning the system off. This is effective in not allowing the rooms to become too cold and speeding up recovery time.
1.3The hot water cylinder can also be fitted with a thermostatic valve which turns off the flow when the cylinder has reached the desired temperature but the heat leak radiator will have to be bigger to cope with the extra load when the tank is isolated.
SAFETY CONTROLS
1.4This primarily consists of a high limit thermostat fitted to the gravity flow pipe set at 80˚C, this thermostat should be connected to the pump so that the pump is turned on if the temperature exceeds 80˚C. This will prevent accidental boiling in the gravity circuit.
1.5It is also recommended to fit a low limit thermostat on the central heating return set at 45˚C, this thermostat will turn the pump off if the return temperature falls below 45˚C.
This will prevent corrosion and condensation within the stove.
CONDENSATION
1.6When filling the boiler with water for the first time, the cold water entering the water jacket can cause condensation to form on the surfaces of the appliance (inside and outside).
1.7In certain conditions this condensation could result in a considerable amount of water, in some cases enough to fill the bottom of the appliance. This could be even worse if the house has recently been
1.8Precautions must be taken to ensure that this build up of condensate does not overflow from the appliance onto any surrounding fabric of the room e.g. carpets.
NOTE - THIS CONDENSATION IS NORMAL DURING FILLING AND DOES NOT INDICATE A FAULTY OR LEAKING STOVE.
NORMAL RUNNING
1.9During normal running this condensation should be minimal if the system is fitted with the low limit thermostat as detailed in 1.22 (above). This low limit thermostat prevents the system pump from running until the stove has reached temperature.
SEASONAL USE
1.10If this appliance is unused for lengthy periods of time it should be periodically checked to ensure that condensation is not building up within the stove.
NOTE – THIS CONDENSATION IS NORMAL AND DOES NOT INDICATE A FAULTY OR LEAKING STOVE.
If the stove is going to be unused for very long periods of time it is recommended to drain the system.
NOTE – Further information on solid fuel central heating systems can be found in the HETAS engineers training manual.
LINK UP SYSTEMS
For information on how to link solid fuel boilers to other heating appliances see Information For Dual System Link Up Methods (PM286). This can be obtained through Stovax.
Call (01392) 474011, email info@stovax.com or visit www.stovax.com for details.
Always seek the advice of a competent person* before linking another heating system to a solid fuel boiler.
In the U.K.
*Registered on the Competent Persons Scheme (GB only) see page 35 / INFO (Republic of Ireland).
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