Vaillant ecotech pro 28 temp controls

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I’m trying to alter the hot water temp and the flow temp on said boiler. I’ve followed the manual, thought I’d set the HW to 55 degrees but when I run the HW it goes to 65 degrees on the display. Obviously rads aren’t on so can’t check on that side. Both temperatures that I’ve ‘set’ are flashing on the display when I go into it and don’t stop flashing when I press the RH ‘tick’ button, as if it’s not confirming the setting? I’ve tried a long press, short press etc. Comfort setting can be changed on and off as per the manual by the way.
Obviously it’s not a massive issue but I’d like to not have to add cold water to the hot for showers etc.
When it’s been serviced, the engineer has never commented on the flow temperature being too high or anything but they generally only put the rads for a bit on to see if they are getting warm.
 
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CBW

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The temperature on the display isn’t what is being delivered at the tap, it’s the temperature of the water in the boiler. If it’s set to 55 and is going up to 65, it’s a little over the 10% but not massively.
 
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I’m trying to alter the hot water temp and the flow temp on said boiler. I’ve followed the manual, thought I’d set the HW to 55 degrees but when I run the HW it goes to 65 degrees on the display. Obviously rads aren’t on so can’t check on that side. Both temperatures that I’ve ‘set’ are flashing on the display when I go into it and don’t stop flashing when I press the RH ‘tick’ button, as if it’s not confirming the setting? I’ve tried a long press, short press etc. Comfort setting can be changed on and off as per the manual by the way.
Obviously it’s not a massive issue but I’d like to not have to add cold water to the hot for showers etc.
When it’s been serviced, the engineer has never commented on the flow temperature being too high or anything but they generally only put the rads for a bit on to see if they are getting warm.
What's the temperature coming out of the taps? It might be the 55°C you're looking for, but if so you're still likely to need to add a small flow of cold.
 
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The minimum output from that boiler is ~ 9.5kw so as long as the DHW demand is > 3.9LPM then the temp should remain at 55C assuming cold water at 20C just now.
 
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It feels just as red hot coming out of the tap but obviously without a thermometer it could be cooler, I set it as low as 45 but it still felt very hot, I’ll set it even lower and try again, below 40 should only be slightly warm. It has to go about 1.5 meters to get to the bathroom tap, so hardly any distance.
 
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Can you measure the hot tap only flowrate by running it into a container for exactly 30 secs, then measure this into a 1 or 2 litre container/milk bottle, X2 to give the flowrate in litres per minute, LPM.
 
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I will do that.
I turned the hw down to the minimum, 35 degrees and after running the hw tap for a couple of mins, the display temp was 47 so it has come down. 47 feels a bit too low for washing up so I’ll set it at 40.
Thanks everyone.
 
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As said, the display does not show the hot water temp, it shows the main heat exchanger temp which will always be higher (by as much as 25 degrees)

Showering is normally done around 38 so 40 or over is hot.
 
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Also this boiler doesn't have a hot water temperature sensor, so it uses some calculations to estimate the actual hot water temperature its putting out, it'll never be 100% exact.
 

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