Hot Water and Central Heating Mode:
The appliance will supply heat to the central heating system as required. A demand for hot water at a tap or shower will override the central heating function for the period of the domestic hot water demand.
When domestic hot water is no longer required the burner and pump will continue to operate until the heatbank is back to the required temperature.
The appliance will then return to the central heating state and its normal mode of operation.
Similarly the hot water is occasionally diverted from the central heating system into the heatbank to maintain the stored primary hot water temperature.
NOTE: If in doubt about the use of the controls ask your installer to assist you.
Central Heating Mode:
When a demand is made for heating by the system controls (i.e. a programmer or room thermostat).
The water diverter valve will open, the pump will energise circu- lating primary water around the heating system and the burner will light. The appliance will operate as necessary to maintain the temper- ature of the radiators at the level set by the adjustment of the Heating Temperature Control. (See Fig. 2.)
If the system no longer requires heat to maintain the desired room temperature, the burner will extinguish. The pump will contin-
ue to run for a short period to dissipate the residual heat from the appliance and then switch off.
| Flow tur- |
|
From | bine | Mains |
radiators |
| cold in |
To |
| Domestic hot |
radiators |
| water out |
|
|
|
|
|
|
| Expansion |
|
|
|
|
|
|
| vessel |
|
|
|
|
| Boiler |
| Pilot obser- |
| Heat |
|
|
| |||
|
|
|
| vation win- | |||
| exchanger |
|
|
| |||
|
|
|
| dow. | |||
|
|
|
|
|
|
| |
| Circulating |
| |||||
|
|
| Slot in | ||||
| pump |
|
| ||||
| Burner |
| front cover. | ||||
|
| Water |
| (O.F. only) | |||
|
| diverter |
|
|
| ||
|
| valve |
|
|
| ||
|
|
| Heatbank |
|
|
| |
Primary |
|
|
|
| |||
Water |
|
|
|
|
|
| |
circulation |
|
|
|
|
| ||
4
