Vaillant ecotec 418 F72 F83 faults

[7up1110]

Hi there,

Hoping for some advice really, had a Suprima HE replaced with the above it's never really worked properly in the 2 months we've had it. The day after it was installed we got a F72 Vaillant came out did next to nothing declared it blocked flow or return, a non boiler issue reset it and and left charging me £98. Next morning F83 so I reset it everything comes on tries to fire the within a few minutes F72.

I established that in the morning if I have F72 or F83 if I reset the boiler and demand hot water only everything is fine no issues, after a few minutes put the heating on too and it works fine everything heats up until the demand from the stat achieved or the schedule ends. But at some point between it going off in the morning to the schedule coming on in the later afternoon one of the F faults will return and I have to repeat the process.

The installer came back and has tried everything including a new pump and managed to get an air lock cleared and all was well until the next morning F83. installers have suggested the last thing that they can think of could be the bypass valve some how not operating correctly meaning the hot water sits for too long after everything goes off, leading to the faults.

Failling that it is the boiler and possibly:

-A fault on the board
-An issue with the loom
-One or both thermistors has an intermittent fault once warm
-An issue with the boiler fan

Has anyone any ideas at all, I feel like I'm about to be stuck between the installer who has been great but is frankly out of ideas and Vaillant who don't seem prepared to come and test the boiler themselves.

Thanks

 

[picasso]

Flow and return the wrong way round ? the flow on the suprima is on the opposite side to the vaillant.

 

[7up1110]

Flow and return the wrong way round ? the flow on the suprima is on the opposite side to the vaillant.

Thanks for the reply, the installer has shown me all the before and after pics he took and they were switched over.

 

[picasso]

No guarantee they were correct on the suprima.

 

[Cal10]

Where is the pump wired to? It should be the wired back to the PCB on the boiler. I’d also change the pump setting to II to make sure it is definitely opening the bypass after demand ends. Get them to double check the 24v link has been removed too.

 

[Deleted member 267285]

Can you post a photo of valves and pipework under the boiler, including where it goes to the pump.

Get them to double check the 24v link has been removed too.

I’m not sure this would create these error codes.

 

[Cal10]

I’m pretty sure it’ll be bypass/pump overrun related so it’s not going to help.

 

[7up1110]

Where is the pump wired to? It should be the wired back to the PCB on the boiler. I’d also change the pump setting to II to make sure it is definitely opening the bypass after demand ends. Get them to double check the 24v link has been removed too.

Yes it's wired back to the boiler, I'll set the pump to II and see if that helps, not sure re the 24v link.

 

[7up1110]

Can you post a photo of valves and pipework under the boiler, including where it goes to the pump.

I’m not sure this would create these error codes.

Only thing under is the gas and the condensate pic of the top of the boiler and airing cuppord are below.

 

[AMBal]

Have a look at my thread here, same boiler (different size), same issue. The bypass needs to be installed and set correctly, the pump cannot be run in modulating mode, needs to be constant.

https://www.diynot.com/diy/threads/vaillant-ecotec-plus-430-f83-error-code.495145/#post-5108110

 

[7up1110]

Have a look at my thread here, same boiler (different size), same issue. The bypass needs to be installed and set correctly, the pump cannot be run in modulating mode, needs to be constant.

https://www.diynot.com/diy/threads/vaillant-ecotec-plus-430-f83-error-code.495145/#post-5108110

Thanks for the reply my bypass valve looks nothing like any I have seen while looking into this is mine a manually set valve and ideally I need an automatic valve?

 

[ianmcd]

just screw the valve down and see what diffence it makes if any, just count the amount of turns and set it back to what it was if it doesnt make any difference, should really have been set up by the installer

 

[7up1110]

just screw the valve down and see what diffence it makes if any, just count the amount of turns and set it back to what it was if it doesnt make any difference, should really have been set up by the installer

Thank I'll give it a try sorry to ask daft questions but if I screw it right down tonight and leave it to see if everything fires up tomorrow that won't cause any other issues? Does screwing it down close it off, open it up or change the pressure needed for the valve to work?

 

[ianmcd]

no just changes the volume of water flowing through the by-pass vave, wont damage anything, try it both ways, fully down and fully up, you have a circulation issue and it could simply be not set right, just count or mark where you started, so you can always put it back to where it was if no difference

 

[7up1110]

no just changes the volume of water flowing through the by-pass vave, wont damage anything, try it both ways, fully down and fully up, you have a circulation issue and it could simply be not set right, just count or mark where you started, so you can always put it back to where it was if no difference

Hi I tried down then up, down did nothing but I left it up today and the heat has come on fine this afternoon but now the boiler temp is 80 I've never seen it that high, is this related the flow temp is set to 75? Thanks for your advice so far