In relation to heating and ventilation equipment fired on oil, gas, solid fuel or renewable energy, an allowance is made for energy consumption in the form of electricity used. This applies to any of the following items:
For an existing dwelling, if the location of the pump is unknown, it may be assumed to be located within the dwelling.
The standard tariff is the on-peak rate unless the heating and/or hot water uses an off-peak tariff. Note that the allowance in this section for fan assisted flues only applies for boilers: fan assisted flues for gas fires should not be counted. See Table 4.9 below.
| Equipment | kWh/year |
|---|---|
| Heating system: | |
| Central heating pump (supplying hot water to radiators or underfloor system) | 130 a) |
| Oil boiler b) – pump (supplying oil to boiler and flue fan) c) | 100 a) |
| Gas fired heating flue fan (if fan assisted flue) such as gas boiler, gas fired heat pump, or gas fired warm air heating | 45 |
| Warm air heating system fans d) | 0.6 x V |
| Keep-hot facility of a combi boiler: | |
| Electricity for maintaining keep-hot facility e) f) | |
| - keep-hot facility, controlled by time clock | 600 |
| - keep-hot facility, not controlled by time clock | 900 |
| Ventilation system: | |
| Mechanical extract ventilation g) | SFP × 1.22 × V |
| Balanced whole house mechanical ventilation fans g) | SFP × 1.22 × V |
| Positive input ventilation (from loft space) | 0 |
| Positive input ventilation (from outside) g) | SFP × 1.22 × V |
| Exhaust air heat pump fans | SFP x air change rate x V |
| Solar water heating pump: | |
| Solar water heating pump, electrically powered | 75 |
| Solar water heating pump, PV powered | 0 |
| Electric shower: | |
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Electricity used by electric shower assumes 6 minute (0.1 hrs) showers with power rating of 9.3 kW. Total kWh for electric showers per year = 9.3*0.1*365*(Number of electric showers * Total showers per day / number of showers) |
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Notes:
a) Default values applied by DEAP. Multiply by a factor of 1.3 if room thermostat is absent. Also see information below on use of pump power data based on pump energy labelling and the Energy Efficiency Index.
b) Applies to all oil boilers that provide main heating, but not if boiler provides hot water only.
c) The same motor operates both the pump and the flue fan. This is usually inside the oil boiler.
d) If the heating system is a warm air unit and there is whole house ventilation, the electricity for warm air circulation should not be included in addition to the electricity for mechanical ventilation. V is the volume of the dwelling. The electric fan on fan coil radiators is recorded in the DEAP Space heating: pumps and fans tab.
e) See notes to Table 5.4 for the definition of keep-hot facility.
f) In the case of an electrically powered keep-hot facility where the power rating of the keep-hot heater is obtained from HARP, the electric part of the total combi loss is taken as:
LE =8.76 x P (kWh/year) (subject to a maximum of the value from Table 5.4)
where P is the power rating of the heater in Watts with the remainder (either 600 – LE or 900 – LE) provided by the fuel. If the power rating of the electric heater is not known assume all the keep-hot energy is supplied by electricity.
g) SFP is specific fan power in W/(litre/sec), see Ventilation and Table 3.7, V is volume of the dwelling in m3
The default electricity consumption value in the DEAP software for each central heating pump is 130 kWh/yr where a room thermostat is installed. Where the boiler is not controlled by a room thermostat, the default electricity consumption per central heating pump is 169 kWh/yr. The BER assessor must specify whether or not the boiler is controlled by a room thermostat.
The user has the option of entering a non-default central heating pump electricity consumption figure in the following scenarios:
| Energy label category1 | Annual electricity consumption (kWh) | |
|---|---|---|
| Boiler controlled by room thermostat | Boiler not controlled by room thermostat | |
| A | 52 | 67.6 |
| B | 78 | 101.4 |
| C | 104 | 135.2 |
| Other / don't know | 130 | 169 |
Where a pump has an Energy Efficiency Index (EEI) value displayed on the pump nameplate or technical data sheet (as required by EU Commission Regulation 641/2009), a CE mark is not required on the data sheet or the pump. The EEI may be used for standalone or integrated pumps. The annual electricity consumption =
If EEI is not given as a fixed figure but as a maximum limit (e.g., EEI <= 0.2), the maximum limit can be used in the formula.
Where multiple central heating pumps are installed, then the BER assessor enters the total electricity consumption based on the calculations above for these pumps along with the number of central heating pumps installed. When not using the default pump electricity consumption, the BER assessor must manually account for the presence (or lack of) the room thermostat as indicated in the sample calculation shown above.
Where manufacturer’s pump curves are used by a manufacturer, supplier, or system designer/specifier to calculate actual installed pump power, it is permitted to use the power consumption as identified on the pump curve. In this case manufacturer’s pump curves with power consumption showing the system operating point as calculated by the pump specifier should be retained by the BER assessor. Commissioning sheets by the installer should also be provided in the case of completed dwellings.
| Space heating: pumps and fans | ||
|---|---|---|
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Guidance on re-use of data for Space heating: pumps and fans can be found here |
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| Data Entry Item | Guidance | Documentary Evidence |
| Central heating pump |
Follow guidance in the DEAP Manual. Details must be recorded on the DEAP Survey Form relating to central heating pumps distributing heat to space heating emitters. Calculations for non-default central heating pump power as per Table 4.9 may be carried out if enough information is available. Efficiency data for central heating pump power can be obtained from pump energy labels as detailed in Table 4.9 above. Also, record presence of room thermostat on heating system and details of pump location (inside or outside dwelling area being assessed). |
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| Oil boiler fuel pumps |
It is likely that an oil boiler will contain an internal fuel pump. There may be another external fuel pump, and this must be accounted for. Details must be recorded on the DEAP Survey Form. Also, record presence of room thermostat on heating system and details of pump location (inside or outside dwelling area being assessed). |
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| Gas boiler flue fan | It is likely that a gas boiler will have a gas boiler flue fan. Details must be recorded on the DEAP Survey Form. |
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| Warm air heating or fan coil radiators present? |
Warm air may be installed as an alternative to radiators or underfloor heating. Warm air heating should not be selected to represent heat recovery systems as related fan power is already accounted for in ventilation tab. Fan coil radiators have an electric fan to distribute heat to the room from the radiator. The electric fan on fan coil radiators is recorded in the DEAP Space heating: pumps and fans tab. Details must be recorded on the DEAP Survey Form. |
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