New central heating system in Macclesfield

The design is the job. Heat loss is calculated room by room from construction, glazing, exposure and target temperature. Radiators are then selected to meet that loss at the system's design flow temperature — and choosing a lower flow temperature, which means slightly larger radiators, is what makes a condensing boiler actually condense and what leaves the house ready for a heat pump later without re-doing the emitters.

Pipework layout follows. Most modern installations use a two-pipe system with correctly sized flow and return runs, and increasingly a manifold arrangement where each radiator has its own pair of pipes back to a central point — which makes balancing simple and future changes easy. Microbore has its place but is unforgiving of sludge and awkward to modify.

Controls are not optional extras. Building Regulations require time and temperature control, and for most installations that means a programmer, a room thermostat, thermostatic radiator valves and, in larger properties, zoning so upstairs and downstairs can be scheduled separately. Weather compensation, where the flow temperature tracks outside conditions, is the single best control upgrade available and is standard on well-specified installations.

Where a house has never had central heating — still occasionally the case in older terraces and cottages — the work is substantial but methodical, and it is dramatically easier while floors are up for other reasons. Where it replaces an old gravity or semi-gravity system, the existing pipework is usually too small and too dirty to reuse, and the honest quote says so rather than connecting new radiators to forty-year-old runs.

Commissioning is where a good installation is separated from an adequate one: flushing and cleaning, inhibitor dosing, filling and venting, setting the pump and flow temperature, balancing every radiator, and configuring the controls with the household rather than leaving a manual on the side.