Several funding streams can help with church heating, though none will cover the full cost on their own. The main ones to look at are the National Churches Trust, which offers grants from £500 to £25,000 for building projects including heating; the Listed Places of Worship Grant Scheme, which reclaims VAT on eligible repairs and alterations to listed buildings; and diocesan funds, which vary by diocese but often have small pots for energy or sustainability projects.
The Church of England's net zero carbon commitment has also opened up new funding. Some dioceses run their own decarbonisation grant schemes, and the National Lottery Heritage Fund sometimes supports heating as part of wider building conservation projects. It is worth checking what your diocese offers before looking further afield.
Start with your Diocesan Advisory Committee. They will know which funds are currently open and can tell you whether your project is likely to qualify. A strong application ties the heating work to the church's wider mission: keeping the building in use, reducing carbon, and making worship accessible in winter. Most funders want to see that the PCC has done its homework on running costs, not just capital cost.