Vaillant Turbomax Repair in Wolverhampton — Diverter Valve Replacement & Plate Heat Exchanger Clean
Some repairs are quick and simple. Others need a bit of experience, a careful diagnosis, and a willingness to do the job properly. This one was the latter, a Vaillant Turbomax in Wolverhampton that was showing classic signs of a diverter valve issue.
The customer had noticed the radiators warming up every time they turned on the hot tap, not ideal in the middle of summer. On top of that, the hot water pressure had dropped, and temperature control wasn’t as sharp as it used to be.
What we found:
The Turbomax is a solid boiler, but after years of use, it’s not uncommon for the diverter valve to start failing. In this case, the valve was passing through to the heating circuit, even when it should’ve been prioritising hot water.
We opened up the boiler and found exactly what we expected: the old diverter valve had worn out internally and was no longer sealing correctly. Left untouched, this kind of fault can slowly drive up energy bills, and frustrate anyone trying to get a quick shower without heating the whole house.
We also decided to inspect the plate-to-plate heat exchanger while the system was drained. It’s not always something you have to replace, sometimes it just needs a proper clean. This one was heavily restricted with debris and sludge build-up, so we removed it and gave it a full internal flush and clean before reinstalling.
The repair process:
With the diagnosis confirmed, we got to work:
Removed the failed diverter valve and fitted a brand-new part, you can see the comparison in the photos.
Cleaned out the plate heat exchanger, flushing out the fine sludge that was reducing hot water performance.
Resealed and tested all connections, then refilled and restarted the system.
Ran full checks on both heating and hot water operation to confirm the job was complete.
We also gave the boiler a general inspection to check for any other signs of wear, no issues found. Just a classic case of components wearing out after a good few years of use.
Why this job mattered:
This is the kind of repair that saves homeowners serious money. Instead of pushing for a full boiler replacement, we focused on restoring performance with two key component fixes, and it worked.
The boiler is now delivering strong, consistent hot water again, and the unwanted heating flow has stopped completely. Most importantly, the customer was left with a reliable system and no more rising energy costs from a constantly firing heating circuit.
Not every fix needs to be a full strip-out or swap, but it does need to be done properly. That’s where our experience pays off.
📍 Job location: Wolverhampton
🛠️ Boiler model: Vaillant Turbomax
⚙️ Issue: Heating coming on with hot water / pressure & temp fluctuations
🔧 Work completed: Diverter valve replacement, plate-to-plate heat exchanger clean
✅ Outcome: System restored to full performance, no more crossover, better hot water delivery
Need a second opinion on your Vaillant boiler? We’re happy to take a look.
📞 Call us on 01902 283124
💬 Message us on WhatsApp 07395088121
🌐 wlvheating.co.uk
