Plumbers & electricians in Lewisham

The town centre sits on low ground where the Quaggy joins the Ravensbourne, and the tall recent blocks have gone up around the station. Walk east towards Hither Green or south west towards Ladywell and the ground lifts into street after street of late Victorian and Edwardian terraces, bay fronted, two and three storeys, built from the eighteen eighties on. Between them sit post war blocks and low rise council housing.

So there is no single heating system in SE13. What the houses share is a history of boilers replaced on their own. The heat source gets swapped every fifteen years or so, the controls hardly ever. A fair amount of what gets booked as boiler repair in Lewisham turns out to be a controls conversation first.

The terraces are also tall for their footprint. Heat leaving a radiator in the front room ends up two floors above it, and comfort depends less on the boiler than on what the system is allowed to switch off, and when.

Why one hall thermostat cannot run a Hither Green terrace

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Most houses have three controls doing three jobs. The programmer decides when heating may run at all. The room thermostat decides whether the boiler fires, based on the one room it happens to stand in. The radiator valves decide how much heat each radiator gives off. Only the thermostat can stop the boiler. A TRV cannot, and that is the part people miss. In a terrace here the thermostat sits in the hall by the front door, and through one zone valve it speaks for the front room, the kitchen and two floors of bedrooms.

From inside, that is a house never right in two places at once. The hall cools every time the front door opens, so the thermostat keeps calling and the top bedrooms become uncomfortable to sleep in. Turn the hall radiator down instead and the opposite happens, the boiler runs far longer than it needs to and the bill rises with nothing to show for it. A TRV in the same room as the thermostat is always arguing with it. Seized pins add to the mess. A head that has sat still since spring often will not move in October, so the radiator is stuck cold or stuck open, and from the room it just looks like the radiator has failed.

The honest fix starts at the cheap end. Free or replace seized pins, take the valve off the radiator in the thermostat’s room or lock it open, and set the programmer to how the house is actually lived in. The real gain in a tall narrow house is then separating the sleeping floors from the living floors, each with its own thermostat and zone valve, and whether that is sensible depends entirely on how the pipework was run. Where one loop has been threaded through joists across decades of alterations it means floors up, and that is worth saying before anyone commits. Smart valves on every radiator in a house with one thermostat only buy a phone app for an argument the valves cannot win.