Why Your Boiler Is Running but the Taps Stay Cold in Oakhanger
It can be worrying when your central heating kicks in, warming radiators, yet there’s no hot water from the taps. In many Oakhanger households, the culprit is often a faulty diverter valve. This vital component directs hot water either to your heating system or to your hot water taps, and when it fails, you lose the latter.
How the Diverter Valve Works Inside Your Boiler
Inside a combi boiler, the diverter valve switches the flow of heated water. When you turn on a tap, it moves to channel hot water to your taps; when you use the heating, it shifts back. In Oakhanger and nearby areas like Bordon (GU35), Alton and Liphook, this mechanism is key to enjoying both heating and hot water on demand.
Common Signs of Diverter Valve Failure
- Radiators heat up but taps stay cold or lukewarm
- Sudden temperature changes when switching between heating and hot water
- Unusual noises—clicking or banging—from the boiler
- Water pressure fluctuations when taps are in use
Troubleshooting Steps You Can Try Before Calling a Pro
Before arranging a service visit in Oakhanger or Petersfield, you can perform basic checks to rule out simple causes:
- Check the boiler pressure gauge. Ideal pressure is 1–1.5 bar; re-pressurise if it’s low.
- Ensure the timer and thermostat settings are correct for hot water mode.
- Inspect the selector switch (if fitted) for dishwasher or bath settings interfering with hot water flow.
- Bleed radiators to eliminate trapped air which can affect system balance.
- Verify that any external valves on your hot water cylinder are fully open.
When the Issue Persists
If you’ve gone through the basic checks and there’s still no hot water, it’s time to call a professional. A stuck or malfunctioning diverter valve typically requires specialised tools and replacement parts. Attempting DIY repairs on gas appliances can be dangerous and will invalidate most warranties.
How Our Gas Safe Engineers Diagnose and Repair Diverter Valve Faults
At Embassy Gas, our Gas Safe engineers cover Oakhanger and surrounding GU35 areas. Here’s what to expect during a visit:
- Full System Inspection: We examine boiler pressures, flow rates and examine the diverter valve’s movement.
- Component Testing: Using diagnostic tools, we confirm if the valve is fully operational or sticking.
- Valve Replacement: If needed, we install a manufacturer-approved diverter valve.
- Safety and Performance Check: Post-replacement, we test for leaks, noise and ensure your hot water supply is restored.
If your boiler is older or experiencing repeated breakdowns, our team can also discuss new boiler installation options in Alton, Liphook and beyond, ensuring efficient heating and reliable hot water.
Preventing Future Diverter Valve Issues
Regular maintenance is key to preventing diverter valve and other boiler component failures. We recommend:
- Annual boiler servicing by a qualified Gas Safe engineer to clean, lubricate and test moving parts.
- Installing a magnetic filter to capture system debris that can clog valves.
- Using an inhibitor chemical to prevent corrosion and limescale build-up.
- Upgrading to a protective boiler cover plan for peace of mind and reduced repair costs.
- Keeping an eye on water pressure and bleeding radiators annually.
Frequently Asked Questions
Q: Can I clean the diverter valve myself?
A: Cleaning usually involves stripping the boiler, which isn’t recommended for non-professionals. Always use a Gas Safe engineer.
Q: How long does a diverter valve replacement take?
A: Most replacements can be completed within 2–3 hours, depending on boiler access and component availability.
Q: Will a faulty diverter valve affect my heating bills?
A: Yes. A partially stuck valve can make your boiler work harder, increasing energy consumption.
Need Help with Your Boiler or Hot Water?
Call us on (01420) 558993 or book online at embassygas.com/book
Written by Embassy Gas — your local heating experts covering Oakhanger, Bordon, Alton, Liphook, Petersfield and surrounding areas.