EcoTech Plus 824 - No water flow from hot taps

[malakoffee]

There is no water flowing when I turn on any of the hot taps.

The boiler is on and the central heating seems to be working well.

The loss of hot water has happened shortly after connecting a new 22mm cold supply pipe ( the old one was 15mm ). My first theory is that debris may have blocked something.

I have already removed/examined/replaced the aqua sensor, to see whether it was jammed, but there is no obvious problem there.

d.22 = 0 = No flow
No faults are showing on the screen currently, but the fault history shows a number of F.22 ( dry fire ).

The DHW did work during a couple of quick tests after the new pipe was connected. Since then there has been no flow at all.
The cold water is ON and has a decent pressure.

What else can I try before contacting Vaillant ?

 

[ukrobj]

Make sure that both the filling loop valves are in the OFF position, I think its the left hand one, will stop the hot water flow.

I know its basic, but is the iso valve on?

Slacken off the nut of the DHW outlet under the boiler, if its pressurised, your know it. Do it slowly! If it is, then boilers probably ok and could be blockage elsewhere.

 

[bobw1956]

Make sure both filling valves are Closed under the boiler

 

[bobw1956]

beat me to it only by 1min though

 

[ukrobj]

beat me to it only by 1min though

Done it too many times (left valve closed) lol

 

[malakoffee]

Thanks for these responses.

(One of) the filling valves may indeed be the prime suspect. It corresponds with something seeming a bit odd when I refilled the CH. . . . . .

At the start, of the CH refill, both tapheads on the filling loop showed closed.
I turned the left one ON and the water started filling the the CH circuit. i.e. the taphead on the right-hand-side was still showing "closed". . . . but it is probably really OPEN . . . and blocking the DHW.

I'm going to nip over to the house now and check the theory.

 

[malakoffee]

Solved !! Many thanks to all contributors.

The valve for the CH filling loop on the right-hand-side ( cold supply IN ) was open to the filling loop while its taphead indicated "Closed".
i.e. taphead had slipped out of the correct position.

I have tightened up the screws on the tapheads and they are now moving the valves as expected and indicating the valve position correctly.

The DHW is back !! Phew.