We have a new Vaillant EcoTec 630 System boiler. There was some issue with the hot water control when it was fitted but I'm not sure what. So that we had hot water, the engineer switched the immersion heater on. It was on for approx 4 hours. The following day, the control issue was apparently fixed so I then switched the hot water on for 1 hour in order for us to have hot water for showers. When we came to have showers, the water was unbearably hot. We changed the temperature on the thermostat from 59 to 40 degrees. That was 3 days ago, the hot water hasn't been switched on since and despite using loads of hot water for baths, washing up etc, the water is still unbearably hot. Any ideas why this is? Surely the water wouldn't stay that hot in the tank for 3 days? Many thanks.
Water too hot - Vaillant Ecotec System Boiler
- Thread starter Murdoch77
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No idea. The immersion heater is definitely off though.
Your talking about the heating coil in the cylinder that's heated by the boiler?, you say its definitely off, you mean programmed off?? but the CH may still be programmed on and heating the cylinder due to some installation problem or valve malfunction, there should be a thermostat attached to the cylinder about 1/4 way up, this should be set to 60C, or it may have a probe inserted somewhere around the same level. Take a few photos around the cylinder and where the coil top pipe enters the cylinder and any motorized valves near by.
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The electric switch for the immersion heater is off. The thermostat attached to the cylinder was on 59 degrees but we turned it down to 40. The hot water has not been switched on or programmed on since Wednesday. That's why we can't understand why it is still so ridiculously hot. The heating has been on a couple of times in the evenings but not the hot water. Photos attached.
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OK, thanks, with the HW programmed on,turn the cylinder stat up slowly unti you hear a click, note the stat setting, see if boiler fires, slowly turn the stat down untul you hear another click, note the setting, does the boiler stop firing.
when finished pull on the manual lever on the motorized valve that supplies the cylinder coil, you shiuld feel a fairly stiff resistance immediately. Programme on the Ch and turn up a roomstat to fire the boiler, again pull on the coil Mot. Valve lever, is there still a stiff resistance?
when finished pull on the manual lever on the motorized valve that supplies the cylinder coil, you shiuld feel a fairly stiff resistance immediately. Programme on the Ch and turn up a roomstat to fire the boiler, again pull on the coil Mot. Valve lever, is there still a stiff resistance?
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Have you tested that the immersion switch has actually turned the immersion off? Could be a faulty switch or the switch has been wired incorrectly.
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I bloody hope so otherwise it's going to cost a fortune. How would we check? The switch is definitely off, I know that much.
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How do you know its off? Is there an indication on the switch or are you relying on the switch position?
ensure all heavy eIec items off like kettle dish waher etc off, if you have a smart elec meter, the LED should be flashing fairly slowly of if not the disc on the older meter should be soinning fairly slowly, run off about 30L of HW, see does LED/disc speed up. If so turn the switch "ON", LED/DISC should slow down.
Have you had the problem ever since the boiler was installed?
Sounds to me like a wiring problem, so the boiler doesn't know the cylinder has reached set temperature, and heats up to something like boiler control-stat setting. Or maybe contacts in the cylinder stat or the HW valve microswitch stuck together.
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