Vaillant ecotec plus 615 system boiler

2 Dec 2018
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United Kingdom
Hi All.
Happy new year.
I have a Vaillant ecotec plus 615 system boiler with tank and the hot water isn't getting hot sometimes , we notice at night when having a shower. it is set to heat water 5am-6:30 11-12 and 6pm till 7:30.
I have checked the boiler when it's heating the water and the radiator light is flashing in heating mode , is that right ?
I have a Hive controls could it be that thats not working correctly.

Many thanks
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Likely a motorised valve not doing its job properly. You’ll likely have a Y-plan or S-plan, likely the latter and probably not hitting the microswitch.
Strange explaination here in view that the water isn't heating?

Understanding the Vaillant Boiler Flashing Radiator Symbol​

The Vaillant boiler flashing radiator symbol can sometimes cause confusion amongst homeowners, but it is generally not a cause for concern. This symbol simply indicates that the boiler recognises an increased heating demand and is working to meet the desired temperature set point. The flashing radiator symbol serves as a notification that the boiler has reached the specified temperature and is now resting, while the pump continues to circulate water until the boiler cools down.

It is important to note that the flashing radiator symbol is not an error message or a warning sign; it is merely an indication that the boiler is functioning as expected. The purpose of the flashing symbol is to inform the user that the heating system is operating efficiently and circulating residual heat throughout the home.

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