# Vaillant Heat Pump, Cockfosters EN4 | Case Study > A 7kW Vaillant aroTHERM plus replacing an old gas boiler in Cockfosters EN4 in three days, raised over gravel so the defrost water drains away. *Climate Shield London — https://climateshieldlondon.co.uk/projects/vaillant-heat-pump-cockfosters-en4/. Verbatim from the page; this is the same content, not a summary.* --- ![The aroTHERM plus raised on feet over a gravel bed.](https://climateshieldlondon.co.uk/assets/img/case/vaillant-arotherm-a-01-960.webp) # A 7kW Vaillant heat pump in Cockfosters An old gas boiler out and a 7kW Vaillant aroTHERM plus in, three days on site, with the grant taken off the price and the unit raised over a gravel bed. [Price my heat pump](https://climateshieldlondon.co.uk/heat-pump-cost-london/#calc-hp) [WhatsApp us](https://wa.me/447875564437?text=Hi%20Climate%20Shield%2C%20I%20have%20seen%20your%20Cockfosters%20EN4%20job%20and%20would%20like%20a%20survey.) - Our own job, photographed on the day - Free survey and a fixed written price - MCS certified, NICEIC approved electrics ## Book a free survey Three taps and your number. Free, and nothing to sign. ## Accredited, and fitting the brands you know ![NICEIC approved contractor](https://climateshieldlondon.co.uk/projects/assets/img/accreditations/niceic-mark.webp) ![Gas Safe Register](https://climateshieldlondon.co.uk/projects/assets/img/accreditations/gas-safe-mark.webp) ![MCS certified](https://climateshieldlondon.co.uk/projects/assets/img/accreditations/mcs-mark.webp) ![RECC, Renewable Energy Consumer Code](https://climateshieldlondon.co.uk/projects/assets/img/accreditations/recc-mark.webp) ![TrustMark, Government Endorsed Quality](https://climateshieldlondon.co.uk/projects/assets/img/accreditations/trustmark-mark.webp) ![Vaillant](https://climateshieldlondon.co.uk/projects/assets/img/brands/vaillant.573f9864.webp) ![Clivet](https://climateshieldlondon.co.uk/projects/assets/img/brands/clivet.15efbad2.webp) ![Samsung](https://climateshieldlondon.co.uk/projects/assets/img/brands/samsung.3b6b3325.webp) ![Daikin](https://climateshieldlondon.co.uk/projects/assets/img/brands/daikin.ce47c11f.webp) ![Mitsubishi Electric](https://climateshieldlondon.co.uk/projects/assets/img/brands/mitsubishi-electric.2977d309.webp) ![Bosch](https://climateshieldlondon.co.uk/projects/assets/img/brands/bosch.7d80a7ce.webp) We replaced an old gas boiler in Cockfosters EN4 with a 7kW Vaillant aroTHERM plus air source heat pump in three days, with the £7,500 grant taken off the price. It now runs the heating and hot water. The unit stands on feet over a gravel bed at the side of the garden, which is a small decision that matters every winter. ## The job at a glance Where Cockfosters EN4, north London Heat pump Vaillant aroTHERM plus 7kW Replaced An old gas boiler Grant £7,500 Boiler Upgrade Scheme Time on site Three days ## How the job was done Step by step, in the photographs taken on site. 1. ![The aroTHERM plus raised on feet over a gravel bed.](https://climateshieldlondon.co.uk/assets/img/case/vaillant-arotherm-a-01-960.webp) 1 Raised over gravel A heat pump defrosts itself on cold days and sheds water as it does. On a solid base with nowhere for it to go, that water pools and freezes round the feet. Over gravel it simply drains away. 2. 2 Three days, start to finish The old boiler came out, the outdoor unit and cylinder went in, and the system was commissioned and handed over within three days. ## Every photograph from the job 3 photographs, no faces, nothing staged. ![The aroTHERM plus raised on feet over a gravel bed.](https://climateshieldlondon.co.uk/assets/img/case/vaillant-arotherm-a-01-960.webp) The aroTHERM plus raised on feet over a gravel bed. ![The unit at the side of the garden.](https://climateshieldlondon.co.uk/assets/img/case/vaillant-arotherm-a-02-960.webp) The unit at the side of the garden. ![The cylinder and controller indoors.](https://climateshieldlondon.co.uk/assets/img/case/vaillant-arotherm-a-03-960.webp) The cylinder and controller indoors. ## Thinking about a heat pump? What this job involved, applied to your own house. [Air source heat pumpsWhole-house heating with the £7,500 grantAir source heat pumps](https://climateshieldlondon.co.uk/air-source-heat-pumps-london/) [What a heat pump costsTen real quotations, before and after the grantWhat a heat pump costs](https://climateshieldlondon.co.uk/heat-pump-cost-london/) [Heat pump or air conditioning?Which one a house actually needsHeat pump or air conditioning?](https://climateshieldlondon.co.uk/air-conditioning-vs-air-source-heat-pump/) [Air-to-air heat pumpsHeats and cools, room by roomAir-to-air heat pumps](https://climateshieldlondon.co.uk/air-to-air-heat-pump-london/) ## Cockfosters EN4: questions about this job ### What is a 7kW heat pump enough for? It depends on the house, not the bedrooms. A 7kW unit heats many three-bedroom London houses, but a draughty one may need more and a well-insulated one less. The heat loss survey gives the number for yours. ### Where does the water from a heat pump go? It drips from the base when the unit defrosts. It needs a gravel bed, a drain or a soakaway beneath it, which is part of choosing where the unit stands. ## More of our finished work Other jobs we have photographed. Tap one for the project. [All 34 projects](https://climateshieldlondon.co.uk/projects/) [![Daikin multi-split condenser in New Southgate N11](https://climateshieldlondon.co.uk/assets/img/projects/new-southgate-n11-ac-840.webp) Air conditioning N11 **New Southgate** Daikin multi-split condenser Wall-mounted on brackets rather than stood on the ground, which is usually what a narrow side return leaves you, and the refrigerant lines dropped in a single trunked run. Read the case study](https://climateshieldlondon.co.uk/projects/daikin-multi-split-new-southgate-n11/)[![Air source heat pump with roof-mounted solar in Winchmore Hill N21](https://climateshieldlondon.co.uk/assets/img/projects/winchmore-hill-n21-840.webp) Heat pump and solar N21 **Winchmore Hill** Air source heat pump with roof-mounted solar The panels sit across the rear pitch and the heat pump at the side of the house, which is the pairing that lets the pump run on its own generation through the middle of the day. Read the case study](https://climateshieldlondon.co.uk/projects/heat-pump-solar-battery-winchmore-hill-n21/)[![Samsung monobloc air source heat pump in Wood Green N22](https://climateshieldlondon.co.uk/assets/img/projects/wood-green-n22-840.webp) Heat pump N22 **Wood Green** Samsung monobloc air source heat pump Stood on a levelled base built up out of the border rather than on soil, so the feet stay out of standing water and the unit does not settle out of level over a winter. Read the case study](https://climateshieldlondon.co.uk/projects/samsung-heat-pump-wood-green-n22/)[![Samsung monobloc air source heat pump in Enfield EN3](https://climateshieldlondon.co.uk/assets/img/projects/enfield-en3-840.webp) Heat pump EN3 **Enfield** Samsung monobloc air source heat pump Set tight against the flank wall on anti-vibration feet, where it takes up none of the usable garden and the pipe run to the cylinder stays short. Read the case study](https://climateshieldlondon.co.uk/projects/samsung-heat-pump-enfield-en3/)[![Vaillant aroTHERM plus 7 kW air source heat pump in Enfield EN3](https://climateshieldlondon.co.uk/assets/img/projects/enfield-en3-vaillant-840.webp) Heat pump EN3 **Enfield** Vaillant aroTHERM plus 7 kW air source heat pump Stood on rubber anti-vibration blocks on the existing patio slabs rather than on a new base, against the rear fence and beside the drainage the house already had. Read the case study](https://climateshieldlondon.co.uk/projects/vaillant-heat-pump-enfield-en3/)[![Air source heat pump with solar and battery storage in Tottenham N15](https://climateshieldlondon.co.uk/assets/img/projects/tottenham-n15-840.webp) Heat pump, solar and battery N15 **Tottenham** Air source heat pump with solar and battery storage The whole electrical side on one wall: inverter, battery modules and every isolator in reach, with the conduit dressed in straight runs so a fault years from now can be traced without stripping the wall. Read the case study](https://climateshieldlondon.co.uk/projects/heat-pump-solar-battery-tottenham-n15/)[![Solar panels on ballasted frames, flat roof in Cricklewood NW2](https://climateshieldlondon.co.uk/assets/img/projects/cricklewood-nw2-solar-1260.webp) Solar and battery NW2 **Cricklewood** Solar panels on ballasted frames, flat roof Low-tilt frames standing on the pebble finish of a new-build flat roof and held down by weight, so nothing is fixed through the waterproofing, with a clear strip left along the parapet to walk and work from. Read the case study](https://climateshieldlondon.co.uk/projects/solar-battery-cricklewood-nw2/)[![Samsung monobloc air source heat pump in Camden NW1](https://climateshieldlondon.co.uk/assets/img/projects/camden-nw1-840.webp) Heat pump NW1 **Camden** Samsung monobloc air source heat pump Levelled on packers on an existing tiled patio rather than bolted through it, so the tiling stays intact and the unit still sits dead flat. Read the case study](https://climateshieldlondon.co.uk/projects/samsung-heat-pump-sunamp-camden-nw1/)[![Samsung Gen 7 12kW high temperature heat pump in North Finchley N12](https://climateshieldlondon.co.uk/assets/img/projects/north-finchley-n12-840.webp) Heat pump N12 **North Finchley** Samsung Gen 7 12kW high temperature heat pump On wall brackets on the side of the house, clear of the ground, which keeps the side passage usable and the coil away from leaves and splashback. Read the case study](https://climateshieldlondon.co.uk/projects/samsung-heat-pump-north-finchley-n12/)[![Cascade pair of air source heat pumps in Barnet EN4](https://climateshieldlondon.co.uk/assets/img/projects/barnet-en4-cascade-840.webp) Heat pump EN4 **Barnet** Cascade pair of air source heat pumps Two machines in cascade on a flat roof, flow and return in insulated copper with isolating valves on each leg, so one can be shut down and worked on while the other keeps the building warm. Read the case study](https://climateshieldlondon.co.uk/projects/cascade-heat-pump-barnet-en4/) ## Book a free heat pump survey We measure every room, calculate the heat loss, check the radiators and the space for a cylinder, and send a written price with the grant already taken off. No cost and no obligation. Call 020 3393 1331 [WhatsApp us](https://wa.me/447875564437?text=Hi%20Climate%20Shield%2C%20I%20have%20seen%20your%20Cockfosters%20EN4%20job%20and%20would%20like%20a%20survey.) Monday to Friday 9am to 7pm, Saturday 10am to 3pm, Sunday closed Page updated 24 September 2026