No Heating but Hot Water in Redditch? 3-Port Valve Case Study

A customer in Redditch contacted Central Heating Hub because their hot water was working but the radiators were not heating. This type of fault can point to the controls or water-routing components rather than the boiler itself, so the first step is proper diagnosis.

The heating system was a Y-plan

The property used a traditional Y-plan arrangement with a single 3-port motorised valve controlling the flow of heated water between the hot-water cylinder and the radiators. This differs from an S-plan system, which normally uses separate 2-port zone valves.

What caused the no-heating fault?

The 3-port valve was not moving correctly to send flow to the heating circuit. A replacement synchronous motor had already been tried, but the underlying valve mechanism was faulty, so changing the motor alone could not restore normal operation. The 22mm 3-port valve was replaced and the system was tested with heating and hot water operating correctly.

Signs a motorised valve may be involved

• Hot water works but the radiators stay cold.

• Heating works only intermittently or only when hot water is also selected.

• The programmer and thermostat appear to call for heat but the system does not respond as expected.

Those symptoms can also have other causes, so they are not a diagnosis on their own. Testing the controls, valve, pump and boiler response is the quickest way to avoid replacing the wrong part.

Boiler and heating repairs in Redditch

If you have no heating, no hot water or an intermittent heating fault in Redditch, see our boiler repair service or call 01527 910345. We cover Redditch and surrounding areas across Worcestershire and the West Midlands.