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Thank you. I’m no expert, I’ll call the boiler engineer. 👍🏻The hot water temperature is not controlled by the boiler thermostat
Water temperature is preset on mixing valve thats between the plate to plate and hot water pump.
It can be altered take of white plastic cap then turn stem of valve probably need grips or pliers.
If water is still hot could be thermistor at that point probably better to get competent oil engineer.
Reply to the thread, titled "Hot water... hot or hotter" which is posted in DIY Plumbing Advice on Plumbers Forums.
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