Vaillant Ecotec Pro 28

Hey people small issue here on my Boiler. It’s a Vaillant Ecotec Pro 28, yesterday I drained the central heating system as I was having some pipe work done for a new towel rad in the bathroom. Also turned the mains water off and opened taps to get all the water out the pipes forgot to turn the boiler off while the taps were on. Turned off when drained system tho. Turned mains on and filled back up and ran P0 to release the air and it fired up no issues. Bled all rads too

After that I’m unable to get hot water. When I turn the hot taps on the boiler doesn’t acknowledge demand for hot water.

Heating is working fine no issues at all, surprising I get a lil hot water when the heatings on. Maybe a min and then it’s cold again.

Just wanted to know your thoughts on possibly what it could be. The repairs will be done by a engineer but anything or any ideas on what it could be would be great.

If it was only the towel rad pipe work then I would say the problem is the aqua sensor is defective or has some dirt lodged inside. The outer case is part of the combustion case, this will need to be removed so its advised this should be carried out by a RGI.

Nathan