Vasillant Turbomax Plus 828E

[peebe]

Help please !!!!
Recently added a new rad to a garage to office conversion.
Don't know if it's a coincidence but now CH does not work. Fires up but shuts down after a few seconds.
Got a gas fitter in to look at it. He contacted Vaillant Tech Support who advised that it was the diverter - problem still exists ( Also the diverter was changed last year).
The plumber says that the water doesn't appear to be leaving the boiler but has checked the pump - OK and checked for blockages - OK

He says it's got him beat & I think he has now given up.

Any suggestions

 

[corgigazza]

Sounds like div valve, remove div valve head and operate valve body manually, with the heating on, may also be auto air vent not venting pump, try undoing vent screw on pump to remove air.

 

[chrishutt]

remove div valve head and operate valve body manually

I don't think you can do this with a Turbomax diverter valve, can you? Perhaps you're thinking of an independent 3 port valve?

 

[corgigazza]

Yes on the 824 you unscrew the locking nut on the valve body and remove the black motor section leaving the spindle connected if the spindle comes of the motor then a new valve complete is required


When the div valve was replaced was it replaced complete ie motor + valve body

 

[ChrisR]

How hard do you have to try, gazza? I've leaned stillsons on a couple and failed to shift them. I've got one stuck in HW, I'll try again!

Peebe look athe valve and you'll see a hole facing you. How big is it. Early ones were about 4mm, late ones more like 8. It matters - the early valves all seem to fail eventually.

 

[peebe]

I've taken the motor section off and tried operating the diverter valve manually - No different, bolier still cuts out when 82C reached. The hole on the valve body is 8mm.
With regards to the auto air vent - is that the black bit on top of th pump that looks like a bicycle inner tube valve dust cap ?

Please help er indoors is getting angry and cold !!!!!!

 

[ChrisR]

Got multimeter? Measure the resistance of the two coils in the motor. There are 4 contacts on the pcb connector, one coil is 1 & 2 and the other is 3 & 4. The motor end the coils are connected 1 & 4 and 2 & 3 !
From memory they're 150 Ohms each.

I believe these are a type of stepper motor so you only get small pulses of 24V at the pcb - hard to check.
You might see the shaft moving through that 8mm hole - which also tells you it's one of the later DV's.

If the motor measures OK and the shaft moves ok (by hand) then it looks like the pcb, unless there's something wrong with the fittings on the shaft.

Must say this would be a quick check if I were there - just try a new DV!

 

[peebe]

Thnaks ChrisR.

I haven't checked then coils yet . Need to get hold of a multimeter. However, the engineer did try a replacement DV when he came but the problem remained. Also. I can see the shaft moving in the hole on the DV.
Does this all suggest that it's the pcb at fault.

Thanks

peebe