Whitfield — air source heat pump
JOB-2291 · 14 Mill Lane, Congresbury BS49 · surveyed 4 Aug · installing 8–10 Sep
DNO approval outstanding
Contract value
£13,400
Heat pump, cylinder, 4 radiators
Customer pays
£4,400
After the grant, before finance
Stage
Pre-install
2 blockers
Estimated margin
23%
£3,082 · 3 team-days
What is holding it up
Two things, both outside Thornbeck, both with a date
| Blocker | With | Since | Chased | Needed by | Status |
|---|---|---|---|---|---|
| G99 connection approval | Western Distribution | 31 Jul | 2 times | 4 Sep | 25 days |
| Signed finance agreement | Customer | 12 Aug | 1 time | 1 Sep | 13 days |
| Cylinder delivery | Ordered, confirmed | — | — | 3 Sep | On schedule |
| Scaffold | Not required | — | — | — | n/a |
The install is booked for 8 September and three team-days are held for it. If the G99 is not back by the 4th, that is three days of six people with nothing to do — which is why the date, not the application, is what the system watches.
Funding
Grant, finance and what the customer actually writes a cheque for
Contract value£13,400
Boiler Upgrade Scheme grant−£9,000
Rate appliedOff gas grid, oil
Customer contribution£4,400
Of which on finance£3,000 over 60 months
Deposit taken£1,400 · 12 Aug
Grant applicationSubmitted 6 Aug
Grant redeemed onCommissioning
Thornbeck carries the grant until commissioning. Nine jobs currently in flight are carrying £65,800 of grant between them. That is working capital, and until now nobody could put a number on it. The rate itself is derived from the property — the fuel it runs on, whether it is on the gas grid, the measure going in — and held as scheme configuration, so it moves when the scheme moves rather than when somebody remembers.
The property
Customer
Enquiry18 Jul
First contact2 min
Survey4 Aug
Quote issued4 Aug, same day
Accepted12 Aug
SourceCustomer referral
Referred by a neighbour Thornbeck fitted solar for in 2024. It converted in 25 days, cost nothing to acquire, and is the third job on that street.
Survey findings and design
Captured on site by Tom Casey, 4 August
| Item | Finding | Design decision | Effect on price |
|---|---|---|---|
| Heat loss | 7.4 kW at design temperature | 8 kW monobloc unit | Baseline |
| Existing radiators | 4 undersized for 45°C flow | Replace 4, keep 7 | +£1,180 |
| Hot water | No cylinder — combi oil | 210 litre unvented cylinder | +£1,640 |
| Pipework | 22mm to airing cupboard, adequate | Reuse | — |
| Unit siting | North-east elevation, 1.2m to boundary | MCS 020: 35.4 dB(A), passes by 1.6 dB | — |
| Electrical supply | 60A main fuse, board has spare ways | No upgrade needed | — |
| Loft | 100mm, uneven | Top up to 300mm | +£420 |
Quote issued at 17:40 the same day. Thornbeck's conversion on same-day quotes is 61%; on quotes issued a week later it is 24%.
MCS 020 noise assessment
Calculated from the positions recorded at survey
Calculated35.4 dB(A)
Limit37.0 dB(A)
Margin1.6 dB
Three positions were tested and this is the worst of them. It passes, but 1.6 dB
is tight enough to be worth moving the unit 600mm along the elevation on the day, rather than
arguing about it afterwards. Tom had this before he left the drive instead of estimating it there
and checking it at a desk on Monday.
Photographs
Site photos24
Consumer unitCaptured
Proposed unit positionCaptured
Loft hatch & accessCaptured
Every radiator11 of 11
The install team sees these before they load the van. Thornbeck's most expensive day is the one where a crew arrives and cannot start.
A heat pump install triggers half a dozen separate notifications, registrations and certificates, each with its own deadline and its own portal. Miss one and the grant is at risk, the warranty is not valid, or the building control notification is late.
What this job has to produce
Tracked from the day the contract is signed, not the week after handover
| Obligation | Body | Trigger | Due | Owner | Status |
|---|---|---|---|---|---|
| MCS installation certificate | MCS / certification body | Commissioning | Within 10 days | F. Adeyinka | Not due |
| Boiler Upgrade Scheme redemption | Ofgem, via MCS number | Commissioning | On certificate | F. Adeyinka | Not due |
| G99 connection approval | Western Distribution | Before install | 4 Sep 2026 | N. Bevan | Outstanding 25 days |
| Building Regulations notification | Competent person scheme | Completion | Within 30 days | F. Adeyinka | Not due |
| Electrical installation certificate | Part P scheme | Completion | On handover | D. Trescothick | Not due |
| Manufacturer warranty registration | Unit manufacturer | Commissioning | Within 28 days | F. Adeyinka | Not due |
| TrustMark lodgement | TrustMark | Completion | Within 10 days | F. Adeyinka | Not due |
| Workmanship warranty | Insurance-backed | Completion | On handover | F. Adeyinka | Not due |
Eight obligations from one job. Multiply by 96 live jobs and it stops being something a person can hold in their head.
Install plan
Three days, one team, everything they need on the van
- Day 1 — Tuesday 8 September
- Day 2 — Wednesday 9 September
- Day 3 — Thursday 10 September
- Handover pack issued
- Aftercare call
Oil is being removed on day one. If anything stops the job after that, the customer has no heating and no hot water. Jobs that disconnect an existing heat source are flagged so they cannot start with an open blocker — which is exactly why the G99 date matters.
Handover pack
MCS certificateOn commissioning
Electrical certificateOn completion
Building Regs noticeWithin 30 days
Warranty documentsOn registration
How to run itReady
Aftercare contactReady
Each document appears in the customer's portal the moment it is issued, rather than arriving as a wallet of paper six weeks later.