Areas we cover

Heating, cooling & plumbing across London & Hertfordshire.

Datum Climate fits boilers and air conditioning and does plumbing and heating in seven towns across South Hertfordshire and London. Every job starts with a free survey and ends with a fixed written price that does not change.

Get my fixed price →

Gas Safe No. 983968Fixed price, no surprisesFree home surveysWe answer the phone

Pick your town

Local enough to come back.

AL1 · AL2 · AL3 · AL4

St Albans

St Albans is the heart of our South Hertfordshire patch. Boiler replacements, air conditioning and plumbing and heating work, surveyed free and priced in writing.

St Albans page →

AL5

Harpenden

Harpenden sits just north of St Albans on our South Hertfordshire patch. We fit boilers and air conditioning and look after plumbing and heating, with a free survey and a written fixed price.

Harpenden page →

AL6

Welwyn

Welwyn is on the northern edge of our South Hertfordshire coverage. Boiler, air conditioning and plumbing and heating work, with a free survey and a fixed written price.

Welwyn page →

AL9 · AL10

Hatfield

Hatfield is covered from our South Hertfordshire patch. We replace boilers, fit air conditioning and handle plumbing and heating, surveyed free and priced in writing.

Hatfield page →

EN6

Potters Bar

Potters Bar is where our South Hertfordshire and London coverage meet. We fit boilers and air conditioning and do plumbing and heating, with a free survey and a fixed written price.

Potters Bar page →

WD6

Borehamwood

Borehamwood is on the southern edge of Hertfordshire, next to London. We fit boilers and air conditioning and handle plumbing and heating, surveyed free and priced in writing.

Borehamwood page →

EN4 · EN5

Barnet

Barnet is part of our London coverage. We replace boilers, fit air conditioning and look after plumbing and heating, with a free survey and a fixed written price.

Barnet page →

Beyond the seven

The wider patch.

Covering St Albans, Harpenden, Welwyn, Hatfield, Potters Bar, Borehamwood, Barnet & across South Hertfordshire and London. Commercial: City of London & Westminster.

Not sure whether we cover your postcode? Ask when you book or call 07521 576338 and a person answers.

Last updated 2026-10-19

Get a real price, not a callback

Sixty seconds, no pressure, no surprises.

Get my price Call 07521 576338