It may be necessary to apply an adjustment to the space and/or water heating efficiency. Provision for such adjustment is made in the ‘Heat source’ tabs under ‘Space heating and water heating’, based on Table 4.6. Examples of factors addressed by Table 4.6 include condensing boilers with under floor heating, heating controls (such as the absence of a boiler interlock), and heat pump system details.
| Heating System | Efficiency % | Responsiveness category1 |
|---|---|---|
| CENTRAL HEATING SYSTEMS WITH RADIATORS OR UNDERFLOOR HEATING | ||
| Gas boilers and oil boilers | ||
| For efficiency, use HARP database. If possible, otherwise use efficiency from Table 4.5. | ||
| Use Table 4.6 for efficiency adjustments. | ||
| Use Table 4.7 for responsiveness category. | ||
| Refer to Group 1 in Table 4.8 for control options and temperature adjustments due to control. | ||
| Micro-cogeneration (micro-CHP) | ||
| See Appendix N. Performance data to be obtained from HARP database. | ||
| Use Table 4.6 for efficiency adjustments. | ||
| Refer to Group 1 in Table 4.8 for control options and temperature adjustments due to control. | ||
| Solid fuel boilers | ||
| For efficiency, use HARP database if possible, otherwise use efficiency from this table. For open fires with back boilers and closed room heaters with boilers the efficiencies are the sum of heat to water and heat to room. | ||
| Refer to Group 1 in Table 4.8 for control options. | ||
| Manual feed independent boiler in heated space (mineral or wood) a) | 60 | 2 |
| Manual feed independent boiler in unheated space (mineral or wood) a) | 55 | 2 |
| Auto (gravity) feed independent boiler in heated space a) | 65 | 2 |
| Auto (gravity) feed independent boiler in unheated space a) | 60 | 2 |
| Open fire with back boiler to radiators | 55 | 3 |
| Closed room heater with back boiler to radiators | 65 | 3 |
| Wood chip/pellet independent boiler | 65 | 2 |
| Stove (pellet-fired) with back boiler to radiators. | 65 | 2 |
| Range cooker boiler (integral oven and boiler) | 45 | 3 |
| Range cooker boiler (independent oven and boiler) | 55 | 3 |
| Note: a) Heated space means within the boundary of the dwelling as defined in Section 1, ’Dwelling dimensions’”. | ||
| Heating System | Efficiency % | Responsiveness |
|---|---|---|
| Electric boilers | ||
| Refer to Group 1 in Table 4.8 for control options | ||
| Direct acting electric boiler | 100 | 1 |
| Electric CPSU in heated space a) | 100 | 2 |
| Dry core storage boiler in heated space a) b) | 100 | 2 |
| Dry core storage boiler in unheated space a) b) | 85 | 2 |
| Water storage boiler in heated space a) b) | 100 | 2 |
| Water storage boiler in unheated space a) b) | 85 | 2 |
|
a) Heated space means within the boundary of the dwelling as defined in Dwelling dimensions. b) Store within boiler capable of meeting all space heating needs |
||
| Heat pumps with radiators or underfloor heating 2 (see also warm air systems) | ||
| Refer to Group 2 in Table 4.8 for control options | ||
| Ground-to-water heat pump (electric) | 320 | From Table 4.7 |
| Ground-to-water heat pump with auxiliary heater (electric) | 300 | From Table 4.7 |
| Water-to-water heat pump (electric) | 300 | From Table 4.7 |
| Air-to-water heat pump (electric) | 250 | From Table 4.7 |
| Exhaust air-to-water heat pump (electric) | 250 | From Table 4.7 |
| Gas-fired, ground or water source | 120 | From Table 4.7 |
| Gas-fired, air source | 110 | From Table 4.7 |
| GROUP HEATING SCHEMES | ||
| If known, use manufacturer’s declared certified efficiency instead of the value in this table. | ||
| Refer to Group 3 in Table 4.8 for control options | ||
| Check Table 4.6 for efficiency adjustment due to controls | ||
| Distribution loss allowed for separately (see Table 11.1). | ||
| Group heating boilers (Also see Table 11.2 for existing buildings) | 75 | 1 |
| ELECTRIC STORAGE SYSTEMS | ||
| Refer to Group 4 in Table 4.8 for control options | ||
| Off-peak tariffs: | ||
| Old (large volume) storage heaters | 100 | 5 |
| Modern (slimline) storage heaters | 100 | 4 |
| Convector storage heaters | 100 | 4 |
| Fan storage heaters | 100 | 3 |
| Modern (slimline) storage heaters with Celect-type control | 100 | 3 |
| Convector storage heaters with Celect-type control | 100 | 3 |
| Fan storage heaters with Celect-type control | 100 | 2 |
| Integrated storage/direct acting heater | 100 | 2 |
| Heating System | Efficiency % | Responsiveness |
|---|---|---|
| ELECTRIC UNDERFLOOR HEATING | ||
| Off-peak tariffs: | ||
| In concrete slab (off-peak only) | 100 | 5 |
| Integrated (storage/direct acting) | 100 | 4 |
| Integrated (storage/direct acting) with low (off-peak) tariff control | 100 | 3 |
| Standard or off-peak tariff: | ||
| In thin screed (45-60 mm, above insulation) | 100 | 2 |
| In timber floor, or immediately below floor covering | 100 | 1 |
| WARM AIR SYSTEMS | ||
| Refer to Group 5 in Table 4.8 for control options | ||
| Gas-fired warm air with fan-assisted flue | ||
| Ducted, on-off control, pre 1998 | 70 | 1 |
| Ducted, on-off control, 1998 or later | 76 | 1 |
| Ducted, modulating control, pre 1998 | 72 | 1 |
| Ducted, modulating control, 1998 or later | 78 | 1 |
| Room heater, with in-floor ducts | 69 | 1 |
| Gas fired warm air with balanced or open flue | ||
| Ducted or stub-ducted. On-off control, pre 1998 | 70 | 1 |
| Ducted or stub-ducted. On-off control, 1998 or later | 76 | 1 |
| Ducted or stub-ducted, modulating control, pre 1998 | 72 | 1 |
| Ducted or stub-ducted, modulating control, 1998 or later | 78 | 1 |
| Ducted or stub-ducted with flue heat recovery | 85 | 1 |
| Condensing | 81 | 1 |
| Oil-fired warm air | ||
| Ducted output (on/off control) | 70 | 1 |
| Ducted output (modulating control) | 72 | 1 |
| Stub duct system | 70 | 1 |
| Electric warm air | ||
| Electricaire system | 100 | 2 |
| Heat pumps3 | ||
| Refer to Group 2 in Table 4.8 for control options | ||
| Ground-to-air heat pump (electric) | 320 | 1 |
| Ground-to-air heat pump with auxiliary heater (electric) | 300 | 1 |
| Water-to-air heat pump (electric) | 300 | 1 |
| Air-to-air heat pump (electric) | 250 | 1 |
| Exhaust air-to-air heat pump (electric) | 250 | 1 |
| Gas-fired, ground or water source | 120 | 1 |
| Gas-fired, air source | 110 | 1 |
| Heating System | Efficiency % | Responsiveness |
|---|---|---|
| ROOM HEATERS | ||
| Refer to Group 6 in Table 4.8 for control options | ||
| If declared efficiency is available, use instead of value from table | ||
| Gas (including LPG) room heaters: | ||
| Gas fire, open flue, pre-1980 (open front) | 50 | 1 |
| Gas fire, open flue, 1980 or later (open fronted), sitting proud of, and sealed to, fireplace opening | 63 | 1 |
| Gas fire or wall heater, balanced flue | 58 | 1 |
| Gas fire, open flue (open fronted), sitting proud of, and sealed to, fireplace opening, with back boiler unit | 63 | 1 |
| Flush fitting live fuel effect gas fire (open fronted), sealed to fireplace opening, with back boiler unit | 40 | 1 |
| Gas fire, closed front, fan assisted (room sealed flue) | 72 | 1 |
| Condensing gas fire | 85 | 1 |
| Flush fitting live fuel effect gas fire (open fronted), sealed to fireplace opening | 40 | 1 |
| Flush fitting live fuel effect gas fire (open fronted), fan assisted, sealed to fireplace opening | 45 | 1 |
| Decorative fuel effect gas fire, open to chimney | 20 | 1 |
|
Gas fire, flueless add additional ventilation requirements under ‘Ventilation’ |
90 | 1 |
| Oil room heaters: | ||
| Room heater, pre 2000 | 55 | 1 |
| Room heater, 2000 or later | 60 | 1 |
| Room heater with boiler (no radiators), pre 2000 | 65 | 1 |
| Room heater with boiler (no radiators), 2000 or later | 70 | 1 |
| Solid fuel room heaters | ||
| Open fire in grate | 30 | 3 |
| Open fire with back boiler (no radiators) | 50 | 3 |
| Closed room heater | 60 | 3 |
| Closed room heater with boiler (no radiators) | 65 | 3 |
| Stove (pellet fired) – with or without back boiler | 65 | 2 |
| Electric (direct acting) room heaters: | ||
| Panel, convector, or radiant heaters * | 100 | 1 |
| Fan heaters | 100 | 1 |
| Portable electric heaters | 100 | 1 |
| *includes water or oil filled electric radiators | ||
| Other room heaters | ||
| Bioethanol fires, flueless | 90 | 1 |
| OTHER SPACE HEATING SYSTEMS | ||
| Refer to Group 7 in Table 4.8 for control options | ||
| Electric ceiling heating | 100 | 2 |
| HOT-WATER-ONLY SYSTEMS | ||
| If water heating from main system, use efficiency of main system | ||
| Electric immersion (on-peak or off-peak) | 100 | N/A |
| Direct acting electric heating (specified where insufficient water heating present in dwelling) | 100 | N/A |
| Back boiler (hot water only), gas | 65 | N/A |
| From a circulator built into a gas warm air system, pre 1998 | 65 | N/A |
| From a circulator built into a gas warm air system, 1998 or later | 73 | N/A |
| Single-point gas water heater (instantaneous at point of use) | 70 | N/A |
| Multi-point gas water heater (instantaneous serving several taps) | 65 | N/A |
| Electric instantaneous at point of use | 100 | N/A |
| Oil boiler/circulator for water heating only | 70 | N/A |
| Solid fuel boiler/circulator for water heating only | 55 | N/A |
| Range cooker with boiler for water heating only: | ||
| Gas, single burner with permanent pilot | 46 | N/A |
| Gas, single burner with automatic ignition | 50 | N/A |
| Gas, twin burner with permanent pilot pre 1998 | 60 | N/A |
| Gas, twin burner with automatic ignition pre 1998 | 65 | N/A |
| Gas, twin burner with permanent pilot 1998 or later | 65 | N/A |
| Gas, twin burner with automatic ignition 1998 or later | 70 | N/A |
| Oil, single burner | 60 | N/A |
| Oil, twin burner pre 1998 | 70 | N/A |
| Oil, twin burner 1998 or later | 75 | N/A |
| Solid fuel, integral oven, and boiler | 45 | N/A |
| Solid fuel, independent oven, and boiler | 55 | N/A |
| From hot-water only group scheme – boilers | 75 | N/A |
| From hot-water only group scheme – CHP | 75 | N/A |
| Boiler | Efficiency (%) |
|---|---|
| Gas boilers (including LPG) 1998 or later | |
| Non-condensing (including combis) with automatic ignition | 73 |
| Condensing (including combis) with automatic ignition | 83 |
| Non-condensing (including combis) with permanent pilot light | 69 |
| Condensing (including combis) with permanent pilot light | 79 |
| Back boiler to radiators (gas fire as secondary heating) | 65 |
| Gas boilers (including LPG) pre-1998, with fan-assisted flue | |
| Low thermal capacity | 72 |
| High or unknown thermal capacity | 68 |
| Combi | 70 |
| Condensing combi | 83 |
| Condensing | 83 |
| Gas boilers (including LPG) pre-1998, with balanced or open flue | |
| Wall mounted | 65 |
| Floor mounted, pre-1979 | 55 |
| Floor mounted, 1979 to 1997 | 65 |
| Combi | 65 |
| Back boiler to radiators (gas fire as secondary heating) | 65 |
| Combined Primary Storage Units (CPSU) (mains gas and LPG) | |
| With permanent pilot (non-condensing) | 70 |
| With automatic ignition (non-condensing) | 74 |
| With permanent pilot (condensing) | 79 |
| With automatic ignition (condensing) | 83 |
| Oil boilers | |
| Standard oil boiler pre-1985 | 65 |
| Standard oil boiler 1985 to 1997 | 70 |
| Standard oil boiler, 1998 or later | 79 |
| Condensing | 83 |
| Combi, pre-1998 | 70 |
| Combi, 1998 or later | 76 |
| Condensing combi | 81 |
| Oil room heater + boiler, pre 2000 | 65 |
| Oil room heater + boiler, 2000 or later | 70 |
| Range cooker boilers (mains gas and LPG) | |
| Single burner with permanent pilot | 46 |
| Single burner with automatic ignition | 50 |
| Twin burner with permanent pilot pre 1998 | 60 |
| Twin burner with automatic ignition pre 1998 | 65 |
| Twin burner with permanent pilot 1998 or later | 65 |
| Twin burner with automatic ignition 1998 or later | 70 |
| Range cooker boilers (oil) | |
| Single burner | 60 |
| Twin burner pre 1998 | 70 |
| Twin burner 1998 or later | 75 |
| Heating system | Multiply efficiency by: | |
|---|---|---|
|
Gas or oil boiler systems with radiators or underfloor heating: The adjustments are to be applied to the space and water heating gross seasonal efficiency for both the HARP value and for efficiency values from Table 4.5. The term ’radiators‘ when connected to a boiler refers to standard radiators, along with lower temperature and fan coil radiators. DEAP automatically calculates these adjustment factors based on user entries. |
||
| (1) Efficiency adjustment due to lower temperature of distribution system: | Main gas | Oil or LPG |
| Condensing boiler with load compensator a) | 1.02 | 1.01 |
| Condensing boiler with weather compensator a) | 1.02 | 1.01 |
| Condensing boiler with under-floor heating a) b) | 1.03 | 1.02 |
| Condensing boiler with thermal store a) | 1 | 1 |
| (2) Efficiency adjustment due to control system | ||
| No thermostatic control of room temperature c) | 0.95 | |
| No boiler interlock c) | 0.95 | |
| Group heating systems: | ||
| (3) Efficiency adjustment due to charging method | ||
| Flat rate charging d) | 0.90 | |
| Heat pumps: | ||
| (4) Efficiency adjustment due to temperature of heat supplied4 | Space | DHW |
| Heat pump with underfloor heating or warm air heat pump | 1.0 | |
| Heat pump with standard radiators without load or weather compensation (regardless of presence of underfloor heating, fan coil or low temperature radiators) e) | 0.7 | |
| Heat pump with standard radiators and load or weather compensation (regardless of presence of underfloor heating, fan coil or low temperature radiators) e) | 0.75 | |
| Heat pump with fan coil or low temperature radiators (regardless of presence of underfloor heating) | 0.85 | |
| Heat pump supplying all DHW tested to IS EN 14511-2 | 0.7 | |
| Heat pump supplying all DHW tested to IS EN 255-3 | 0.75 | |
| Heat pump supplying 50% or 75% DHW | 1.0 | |
| Range cooker boilers gas or oil fired: | ||
| The following adjustment is to be applied only to the space heating gross seasonal efficiency (not water heating efficiency), and only where the efficiency is obtained from the HARP database or manufacturer’s declared value. ‘Фcase’ is the heat emission from the case of the range cooker at full load (in kW); and ‘Фwater’ is the heat transferred to water at full load (in kW). Фcase and Фwater are obtained from the database record for the range cooker boiler or manufacturer’s declared value. | ||
| Range cooker boiler gas or oil fired | 1 + (Фcase / Фwater) | |
Notes:
a) These are mutually exclusive and therefore do not accumulate; if more than one applies, the highest applicable efficiency adjustment is to be used. These do not apply if there is passive flue gas heat recovery. Weather compensators are located outside the dwelling. Load compensators are located inside.
b) Adjustment is applicable if the boiler supplies only the underfloor heating, and not if it also feeds radiators or supplies hot water. Radiator systems designed to operate at the same temperature as underfloor heating as outlined in note (e) below can also use these factors if the boiler does not supply hot water.
c) These do not accumulate as no thermostatic control or presence of a bypass means that there is no boiler interlock. However, if the system is such that interlock is achieved using an alternative to ’thermostatic control‘ (even if there is a bypass in the system), then both ’No thermostatic control of room temperature‘ and ’No boiler interlock‘ should both be set to “NO” so that DEAP will account for the presence of the interlock mechanism. The assessor should keep a record of how the interlock’s presence was determined in this scenario.
d) ‘Flat rate charging’ means that households pay for the heat according to a fixed monthly or annual amount, not depending on the amount of heat actually used. If the charges vary within a scheme for other reasons, for example according to dwelling size, it is still classified as flat rate. ’Charging based on heat consumed‘ means that charges are based on the amount of heat used rather than being charged at a flat rate.
e) The heat pump section provides guidance on derivation of design flow temperature as used by DEAP when deriving the efficiency adjustment factor where Ecodesign based data is not in use for the heat pump.
| Heat emitter | Responsiveness category |
|---|---|
| Systems with radiators (standard or fan coil or low temperature): | 1 |
| Underfloor heating (wet system): | |
| - pipes in insulated timber floor | 1 |
| - pipes in screed above insulation | 2 |
| - pipes in concrete slab | 4 |
Where underfloor heating in concrete slab and radiators are both in use then responsiveness category is defined as follows:
a) responsiveness category is 2 if the room defined as the living area is heated using radiators
b) otherwise, responsiveness category is 3.
For electric underfloor heating responsiveness see Table 4.4.
| Type of control | Control category | Temperature adjustment (°C) | Ref. to other possible adjustments |
|---|---|---|---|
| GROUP 1: BOILER SYSTEMS WITH RADIATORS OR UNDERFLOOR HEATING | |||
| No time or thermostatic control of room temperature | 1 | +0.6 | Table 4.6(2) |
| Programmer, no room thermostat | 1 | +0.6 | Table 4.6(2) |
| Room thermostat only | 1 | 0 | Table 4.6(2) |
| Programmer + room thermostat | 1 | 0 | Table 4.6(2) |
| Programmer + at least two room thermostats | 2 | 0 | Table 4.6(2) |
| Programmer + room thermostat + TRVs | 2 | 0 | Table 4.6(2) |
| Programmer + TRVs (likely to include bypass) | 2 | 0 | Table 4.6(2) |
| Programmer + TRVs + flow switch | 2 | 0 | Table 4.6(2) |
| Programmer + TRVs + boiler energy manager | 2 | 0 | Table 4.6(2) |
| Time and temperature zone control | 3 | 0 | Table 4.6(2) |
| Adjustments for features of control systems: | |||
| (applicable to any control option above and in addition to the adjustments selected above) | |||
| Delayed start thermostat | one of the above | -0.15 | N/A |
| Load or weather compensation | one of the above | 0 | Table 4.6(1) |
| Temperature control of water heating (cylinder stat) | N/A | N/A | Tables 5.1 and 5.3 |
| Time control of water heating (separate programming) | N/A | N/A | Table 5.1 |
| Adjustments for features other than controls: | |||
| Temperature adjustment for CPSU or integrated thermal stores | N/A | -0.1 | N/A |
| Underfloor heating | N/A | N/A | Table 4.6(1) |
| GROUP 2: HEAT PUMPS WITH RADIATORS OR UNDERFLOOR HEATING | |||
| No time or thermostatic control of room temperature | 1 | +0.3 | Table 4.6(4) |
| Programmer, no room thermostat | 1 | +0.3 | Table 4.6(4) |
| Room thermostat only | 1 | 0 | Table 4.6(4) |
| Programmer + room thermostat | 1 | 0 | Table 4.6(4) |
| Programmer + at least two room thermostats | 2 | 0 | Table 4.6(4) |
| Programmer + room thermostat + TRVs + bypass | 2 | 0 | Table 4.6(4) |
| Time and temperature zone control | 3 | 0 | Table 4.6(4) |
|
Adjustments for features of control systems: (applicable to any control option above and in addition to the adjustments selected above) |
|||
| Load or weather compensation | one of the above | 0 | Table 4c(4) |
| Temperature control of water heating (cylinder stat) | N/A | N/A | Tables 5.1 and 5.3 |
| Time control of water heating (separate programming) | N/A | N/A | Table 2 |
| GROUP 3: GROUP HEATING SCHEMES | |||
| No thermostatic control of room temperature | 1 | +0.6 | Table 4.6(3) |
| Programmer and room thermostat | 1 | 0 | Table 4.6(3) |
| Programmer and TRVs | 2 | 0 | Table 4.6(3) |
| Time and temperature zone control | 3 | 0 | Table 4.6(3) |
| (Programmer in group heating scheme may be inside dwelling or part of the group heating system) | |||
| GROUP 4: ELECTRIC STORAGE SYSTEMS | |||
| Manual charge control | 3 | +0.3 | N/A |
| Automatic charge control | 3 | 0 | N/A |
| Celect-type controls | 3 | 0 | N/A |
| GROUP 5: WARM AIR SYSTEMS | |||
| No thermostatic control of room temperature | 1 | +0.3 | N/A |
| Programmer, no room thermostat | 1 | +0.3 | N/A |
| Room thermostat only | 1 | 0 | N/A |
| Programmer + room thermostat | 1 | 0 | N/A |
| Programmer and at least two room thermostats | 2 | 0 | N/A |
| Time and temperature zone control | 3 | 0 | N/A |
| GROUP 6: ROOM HEATER SYSTEMS | |||
| No thermostatic control | 2 | +0.3 | N/A |
| Appliance thermostat | 3 | 0 | N/A |
| Appliance thermostat + programmer | 3 | 0 | N/A |
| Programmer + room thermostat | 3 | 0 | N/A |
| Room thermostat only | 3 | 0 | N/A |
| GROUP 7: OTHER SYSTEMS | |||
| No thermostatic control of room temperature | 1 | +0.3 | N/A |
| Programmer, no room thermostat | 1 | +0.3 | N/A |
| Room thermostat only | 1 | 0 | N/A |
| Programmer + room thermostat | 1 | 0 | N/A |
| Temperature zone control | 2 | 0 | N/A |
| Time and temperature zone control | 3 | 0 | N/A |