Mountain Ash: plumbing, heating and air-conditioning companies
Mountain Ash has 6 plumbing, heating and air-conditioning companies (SIC 43220) and 18 electrical and other installation companies registered here (Companies House, 1 Sep 2026); 0 are MCS-certified for air-to-air yet. If the office is in CF45, summer 2026 had ≈4 nights above 18 °C there (24 times the 1991–2020 average of 0.2).
SIC 43220
Open a company
GASCO LTD, incorporated 1994, status Active.
Plumbing, heating and air-conditioning companies
| Company | Incorporated | Status | District |
|---|---|---|---|
| GASCO LTD | 1994 | Active | CF45 |
| M&ECONNECT LIMITED | 2024 | Active | CF45 |
| R&D SPRINKLERS LIMITED | 2026 | Active | CF45 |
| SAFE GAS WALES LTD | 2009 | Active | CF45 |
| GREENER HOMES PLUMBING & HEATING LTD | 2022 | Active | CF45 |
| TEMP AIR SERVICES LTD | 2024 | Active - Proposal to Strike off | CF45 |
Electrical and other installation companies
| Company | SIC | Incorporated | Status | District |
|---|---|---|---|---|
| MDC ELECTRICAL SERVICES LTD | 43210 · electrical installation | 2012 | Active | CF45 |
| G&M WATERS DRYLINING LIMITED | 43290 · other construction installation | 2023 | Active | CF45 |
| RELECSERV LTD | 43210 · electrical installation | 2022 | Active | CF45 |
| NEUTRALIVE ELECTRICAL LTD | 43210 · electrical installation | 2026 | Active | CF45 |
| D C L ELECTRICS LTD | 43210 · electrical installation | 2021 | Active | CF45 |
| AJR ELECTRICAL SERVICES & CONTRACTORS LIMITED | 43210 · electrical installation | 2022 | Active | CF45 |
| BRICKZEN CONSTRUCTIONS LTD | 43290 · other construction installation | 2026 | Active | CF45 |
| CY ELECTRICAL LIMITED | 43210 · electrical installation | 2024 | Active | CF45 |
| GSP ELECTRICIANS LTD | 43210 · electrical installation; 43290 · other construction installation; 41202; 43390 | 2021 | Active | CF45 |
| MONMOUTHSHIRE ELECTRICAL MAINTENANCE SERVICES LIMITED | 43210 · electrical installation | 1995 | Active | CF45 |
| SMART ELECTRICAL RAIL LTD | 43210 · electrical installation | 2015 | Active | CF45 |
| SMART ELECTRICAL SYSTEMS LTD | 43210 · electrical installation; 33140; 42990; 71129 | 2012 | Active | CF45 |
| SMART RAIL SYSTEMS LTD | 43210 · electrical installation | 2015 | Active | CF45 |
| DIAMOND DESIGN INTERIORS BUILDING AND MAINTENANCE LIMITED | 43290 · other construction installation; 41202 | 2023 | Active | CF45 |
| SLS CCTV LTD | 43210 · electrical installation | 2025 | Active | CF45 |
| OAK RENDERING CONTRACTORS LTD | 43290 · other construction installation | 2025 | Active - Proposal to Strike off | CF45 |
| A&G ELECTRICAL CONTRACTORS LTD | 43210 · electrical installation | 2018 | Active - Proposal to Strike off | CF45 |
| DFO ELECTRICAL LTD | 43210 · electrical installation | 2014 | Active - Proposal to Strike off | CF45 |
Heat and planning around Mountain Ash
In Mountain Ash last summer (2026) there were ≈4 nights that stayed above 18 °C — 24 times the 1991–2020 average of 0.2 (ERA5 reanalysis, grid ≈30 km, lower than street temperatures in cities). The figure is the household-weighted mean of 1 postcode districts where these offices are registered.
0% of sampled postcodes in Mountain Ash sit in a conservation area (436 live postcodes across 1 districts).
In Wales an air-source heat pump on a house can be permitted development under Class G when the conditions hold, including the MCS 020a noise limit of 37.0 dB(A) (§3.2 Step 8).
Companies House snapshot 1 Sep 2026, retrieved 25 Sep 2026. The address shown is the registered office, not a verified operating base. This catalogue is a directory of incorporated businesses, not an exhaustive installer register. Hot nights: ERA5-ARCO, June–August, minimum at or above 18 °C, household-weighted across the districts where these offices are registered, retrieved 25 Sep 2026. Conservation-area share: sampled postcode points, snapshot 25 Sep 2026. Distances are an equirectangular approximation to 0.1 km.
Better than a town directory that only lists names: each plumbing company links to its Companies House record and the local hot-night count.