Vaillant TURBOmax Plus 828E Issues

[norbury85]

I currently have two issues with my Vaillant TURBOmax Plus 828E boiler, which have been confirmed by two different independent plumbers.

1. The boiler randomly turns on throughout the day & night, A plumber has recently changed the PCB, timing clock and thermostat but this has not resolved the issue. Both plumbers have no idea why this is happening. Do anyone know what else could cause this?


2. Only the first few radiators around the system get hot, these are located upstairs. The system has been drained and bled several times, also balanced. Both plumbers think it is the pump as its no longer strong enough to get the water around the system. The current pump model is Grundfos 161015 which is really hard to come by, but apparently I could use a Grundfos 160928?

Please also see attached images for references.

Many thanks in advance.

James

Untitled

• norbury85
• 29 Jul 2013
• 1

Untitled

• norbury85
• 29 Jul 2013
• 1

 

[picasso]

Your first issue is probably the dhw preheat keeping the heatexchanger hot, if you want to turn it off turn the hot water knob all the way off and then put it back but not fully hot or you will turn the preheat back on,

as your plumber has changed a pcb , clock and stat I wouldent take his advice about the pump, you need a better "plumber"

 

[norbury85]

Your first issue is probably the dhw preheat keeping the heatexchanger hot, if you want to turn it off turn the hot water knob all the way off and then put it back but not fully hot or you will turn the preheat back on,

as your plumber has changed a pcb , clock and stat I wouldent take his advice about the pump, you need a better "plumber"

Hi,

Thanks for the quick reply. I have just followed your direction and turned off the preheat. I should also add the radiators used to randomly turn on in the day and night even though the timer, thermostat and heating was switched off, I think this has been resolved by changing the PCB, but I have not fully tested this as its quite hot ATM.

Many thanks for you help .

James

 

[Dan Robinson]

That sounds more like a guffed diverter valve being affected by the preheat.

 

[norbury85]

That sounds more like a guffed diverter valve being affected by the preheat.

Hi Dan,

Thanks for your response. do you think the diverter valve is effecting the flow of water around the system rather than the pump or the boiler randomly turning on?

Cheers,

James

 

[Gasescape]

If your preheat is activated & the diverter is passing , this would allow water to pass into your heating circuit,
To find out if it's passing turn on the hot tap & feel the flow pipe to the radiators ,if it gets reasonably hot & the rads start heating then it's passing.

 

[Dan Robinson]

Like what he said.

Far more likely than a duff pcb that's for sure.

 

[norbury85]

If your preheat is activated & the diverter is passing , this would allow water to pass into your heating circuit,
To find out if it's passing turn on the hot tap & feel the flow pipe to the radiators ,if it gets reasonably hot & the rads start heating then it's passing.

Thanks

I turned off the pre-heat last night. Maybe I should turn it back on to test your suggestion and out of curiosity for myself.

If the "diverter is passing" would I require it replaced or turned off ?

What could be a good test to check the pump?

Many thanks.

James

 

[Gasescape]

Best deal with the diverter 1st
You may find that the pump's fine & the diverter is causing the problem.
Why not get a descent registered gas installer to take a look

Personally ,I'd replace a passing diverter.

 

[norbury85]

Best deal with the diverter 1st
You may find that the pump's fine & the diverter is causing the problem.
Why not get a descent registered gas installer to take a look

Personally ,I'd replace a passing diverter.

Thanks, I thought I did get someone decent until I saw the advice on here....

James

 

[Gasescape]

Best deal with the diverter 1st
You may find that the pump's fine & the diverter is causing the problem.
Why not get a descent registered gas installer to take a look

Personally ,I'd replace a passing diverter.

Thanks, I thought I did get someone decent until I saw the advice on here....

James

As you said , turn on the preheat & feel the flow to the rads ...
Fairly simple test to see if it's passing.

 

[norbury85]

Best deal with the diverter 1st
You may find that the pump's fine & the diverter is causing the problem.
Why not get a descent registered gas installer to take a look

Personally ,I'd replace a passing diverter.

Thanks, I thought I did get someone decent until I saw the advice on here....

James

As you said , turn on the preheat & feel the flow to the rads ...
Fairly simple test to see if it's passing.

Thanks, I will check.

 

[Agile]

I always suggest a boiler engineer rather than a "plumber".

By now you should have been able to discover if the random firing was just caused by the DHW preheat.

Amazing if your plumber changed an expensive PCB without considering the preheat.

The diverter valves have been a problem with that model and were modified.

The early ones had holes round the outside about 4.7mm diameter whereas the later ones usually had holes about 6 mm diameter. The later ones rarely had sticking problems.

Tony

 

[norbury85]

I always suggest a boiler engineer rather than a "plumber".

By now you should have been able to discover if the random firing was just caused by the DHW preheat.

Amazing if your plumber changed an expensive PCB without considering the preheat.

The diverter valves have been a problem with that model and were modified.

The early ones had holes round the outside about 4.7mm diameter whereas the later ones usually had holes about 6 mm diameter. The later ones rarely had sticking problems.

Tony

Thanks for your reply.

Yeah they are both Gas Safe Registered, I probably should have said this rather than plumber.

I will look into the diverter valve and see if I can get one fitted once I have run a test or two.

Many thanks,

James

 

[norbury85]

I very easily turned off thee preheat (in about 15 seconds) and I got a new plumber on board, he changed the diverter valve.

Everything now works perfectly.

Thanks or everyone's help.

Regards,

James