A truly dreadful experience. What went wrong? Everything but the in-house design (which was okay) was subcontracted so nothing was seemingly EPC's responsibility - someone else. The in-house engineer/plumber was incompetent. The subcontractor installed the heat pump plumbing wrongly, then the commissioning results and commissioning certificate were fiddled to make everything seem okay. The reality was that the heating system was incapable of being commissioned: radiators never exceeded 33C - hopeless. And it took months for EPC to accept responsibility. The PV installation never happened after 7 months and we had to go elsewhere. Then EPC kept the deposit... EPC backed away from their guarantees and in any case we do not want their service as maintainers: we have no confidence in the company. However, EPC was remarkably prompt in collecting the BUS grant, which they keep! Never a hint of an apology... I could say a lot more...