Just for reference, in case anyone has the same problem, my Vaillant non-condensing Turbomax 628 or is it 828 ? combi, now 9 years old, has been a little intermittent lately, with hot water sometimes not coming through. However, it always fixed itself quickly. Not today.

The diagnostic code was S.33 wich points to the fan/pressure switch.

Indeed I couldn't pick up any voltage to the fan at the circuit board connector when I turned the hot water on or tried the CH. The pump ran, the diverter valve diverted etc.

The diagnostic booklet flow chart simply tells you to change the pcb at this point.

I prised the plastic back covers off the pcb had a look. The central (mains voltage) area smelt of ozone. Ozone meant sparking, but I couldn't figure out what might be sparking. Well a few attempts at turning a hot tap on and tapping things soon provided an explanation - greenish-blue arcing inside one of three large relays (transparent cover).

Prising the transparent cover off allowed access and bit of a scrape of the changeover contacts later (using wet and dry) and the relay closed without continual fizzing and arcing (a slight spark but that's normal for an inductive load like a motor). However, still no 240V at the fan motor connector!

I isolated the mains and set to buzzing out the route between line at the mains LIVE input screw terminal, the relay contacts and the brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER) revealed that the contacts were now making too light a contact to work. A bit of adjustment with a fine blade on the live fixed relay contact soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

A word of warning - to gain access to the relays you have to take a second protective cover off the pcb, the high voltage bit. There are plenty of terminals at mains voltage including the mains transformer terminals which are very in-the-way. Don't work on live mains equipment unless you know what you are about.

On Tuesday, 28 August 2012 17:28:24 UTC+1, (unknown) wrote:
Just for reference, in case anyone has the same problem, my Vaillant non-condensing Turbomax 628 or is it 828 ? combi, now 9 years old, has been a little intermittent lately, with hot water sometimes not coming through. However, it always fixed itself quickly. Not today.



The diagnostic code was S.33 wich points to the fan/pressure switch.



Indeed I couldn't pick up any voltage to the fan at the circuit board connector when I turned the hot water on or tried the CH. The pump ran, the diverter valve diverted etc.



The diagnostic booklet flow chart simply tells you to change the pcb at this point.



I prised the plastic back covers off the pcb had a look. The central (mains voltage) area smelt of ozone. Ozone meant sparking, but I couldn't figure out what might be sparking. Well a few attempts at turning a hot tap on and tapping things soon provided an explanation - greenish-blue arcing inside one of three large relays (transparent cover).



By the way I isolated the mains before I started to poke around inside the relay!

Prising the transparent cover off allowed access and bit of a scrape of the changeover contacts later (using wet and dry) and the relay closed without continual fizzing and arcing (a slight spark but that's normal for an inductive load like a motor). However, still no 240V at the fan motor connector!



I isolated the mains and set to buzzing out the route between line at the mains LIVE input screw terminal, the relay contacts and the brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER) revealed that the contacts were now making too light a contact to work. A bit of adjustment with a fine blade on the live fixed relay contact soon brought the clearances back into kilter and I now have hot water again.



I may have to replace that relay in future but I'll see how it goes.



A word of warning - to gain access to the relays you have to take a second protective cover off the pcb, the high voltage bit. There are plenty of terminals at mains voltage including the mains transformer terminals which are very in-the-way. Don't work on live mains equipment unless you know what you are about.

wrote:
Just for reference, in case anyone has the same problem, my Vaillant non-condensing Turbomax 628 or is it 828 ? combi, now 9 years old, has been a little intermittent lately, with hot water sometimes not coming through. However, it always fixed itself quickly. Not today.

The diagnostic code was S.33 wich points to the fan/pressure switch.

Indeed I couldn't pick up any voltage to the fan at the circuit board connector when I turned the hot water on or tried the CH. The pump ran, the diverter valve diverted etc.

The diagnostic booklet flow chart simply tells you to change the pcb at this point.

I prised the plastic back covers off the pcb had a look. The central (mains voltage) area smelt of ozone. Ozone meant sparking, but I couldn't figure out what might be sparking. Well a few attempts at turning a hot tap on and tapping things soon provided an explanation - greenish-blue arcing inside one of three large relays (transparent cover).

Prising the transparent cover off allowed access and bit of a scrape of the changeover contacts later (using wet and dry) and the relay closed without continual fizzing and arcing (a slight spark but that's normal for an inductive load like a motor). However, still no 240V at the fan motor connector!

I isolated the mains and set to buzzing out the route between line at the mains LIVE input screw terminal, the relay contacts and the brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER) revealed that the contacts were now making too light a contact to work. A bit of adjustment with a fine blade on the live fixed relay contact soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

A word of warning - to gain access to the relays you have to take a second protective cover off the pcb, the high voltage bit. There are plenty of terminals at mains voltage including the mains transformer terminals which are very in-the-way. Don't work on live mains equipment unless you know what you are about.

WhenI bough t my old XJS about three of the relays controlling high
current things like the heated rear window and so on had failed in the
way you describe.

filing and buffing the contacts worked for another 5 years...till I sold
it..


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

In message ,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil


A word of warning - to gain access to the relays you have to take a
second protective cover off the pcb, the high voltage bit. There are
plenty of terminals at mains voltage including the mains transformer
terminals which are very in-the-way. Don't work on live mains equipment
unless you know what you are about.

Turn the bugger off ... simples !


--
geoff

geoff wrote:
In message ,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between line
at the mains LIVE input screw terminal, the relay contacts and the
brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to
work. A bit of adjustment with a fine blade on the live fixed relay
contact soon brought the clearances back into kilter and I now have hot
water again. I may have to replace that relay in future but I'll see how
it goes.

Fan control relay - back EMF of the coil


A word of warning - to gain access to the relays you have to take a
second protective cover off the pcb, the high voltage bit. There are
plenty of terminals at mains voltage including the mains transformer
terminals which are very in-the-way. Don't work on live mains
equipment unless you know what you are about.

Turn the bugger off ... simples !

You should consider this sort of thing for a living geoff.

--
Adam

On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

MBQ

On Aug 28, 7:58*pm, "ARWadsworth"
wrote:
geoff wrote:
In message ,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between line
at the mains LIVE input screw terminal, the relay contacts and the
brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to
work. A bit of adjustment with a fine blade on the live fixed relay
contact soon brought the clearances back into kilter and I now have hot
water again. I may have to replace that relay in future but I'll see how
it goes.

Fan control relay - back EMF of the coil

You should consider this sort of thing for a living geoff.

Given that comment, I would not employ him.

MBQ

In message
, Man
at B&Q writes
On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

regards

--
Tim Lamb

In message
,
Man at B&Q writes
On Aug 28, 7:58*pm, "ARWadsworth"
wrote:
geoff wrote:
In message ,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between line
at the mains LIVE input screw terminal, the relay contacts and the
brown wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to
work. A bit of adjustment with a fine blade on the live fixed relay
contact soon brought the clearances back into kilter and I now have hot
water again. I may have to replace that relay in future but I'll see how
it goes.

Fan control relay - back EMF of the coil

You should consider this sort of thing for a living geoff.

Given that comment, I would not employ him.

I was using noddy language in a noddy thread (a bit like people who
misuse the term "dry joint")
Its actually the energy stored in the fan coil when the relay contacts
open arcing across the contacts that knackers the relay

Would I want you as an employer - I think not


--
geoff

In message
, Man
at B&Q writes
On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Oh do **** off


--
geoff

Man at B&Q wrote:
On Aug 28, 7:58 pm, "ARWadsworth"
wrote:
geoff wrote:
In message
,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between
line
at the mains LIVE input screw terminal, the relay contacts and
the brown wire (live) on the fan connector (WITH A dvm SET TO
AUDIO BUZZER) revealed that the contacts were now making too
light a contact to
work. A bit of adjustment with a fine blade on the live fixed
relay contact soon brought the clearances back into kilter and
I now have hot water again. I may have to replace that relay in
future but I'll see how it goes.

Fan control relay - back EMF of the coil

You should consider this sort of thing for a living geoff.

Given that comment, I would not employ him.

Why?

--
Adam

On Aug 29, 9:20*am, Tim Lamb wrote:
In message
, Man
at B&Q writes









On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

MBQ

On Aug 29, 8:10*pm, "ARWadsworth"
wrote:
Man at B&Q wrote:
On Aug 28, 7:58 pm, "ARWadsworth"
wrote:
geoff wrote:
In message
,
writes
the fan motor connector!

I isolated the mains and set to buzzing out the route between
line
at the mains LIVE input screw terminal, the relay contacts and
the brown wire (live) on the fan connector (WITH A dvm SET TO
AUDIO BUZZER) revealed that the contacts were now making too
light a contact to
work. A bit of adjustment with a fine blade on the live fixed
relay contact soon brought the clearances back into kilter and
I now have hot water again. I may have to replace that relay in
future but I'll see how it goes.

Fan control relay - back EMF of the coil

You should consider this sort of thing for a living geoff.

Given that comment, I would not employ him.

Why?

Either he doesn't understand back EMF or he can't explain himself
clearly. In this case the latter. If he'd said "fan coil" (a strange
term in itself) then it would hev been clearer.

MBQ

In message
, Man
at B&Q writes
On Aug 29, 9:20*am, Tim Lamb wrote:
In message
, Man
at B&Q writes









On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot
water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

Hmm.. I think you know what was meant:-)

regards

--
Tim Lamb

In message
, Man
at B&Q writes
I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.


No it doesn't you retard

I admit that I could have actually stated which coil I was on about, but
I expected people to have a bit more of a clue than yourself and
understand that I was on about the fan coil, as that is what the
contacts of the relay are switching

People like you are the reason that manufacturers of toasters have to
put warnings on them stating that it gets hot ...
Get back under your bridge


--
geoff

On Aug 30, 8:09*pm, geoff wrote:
In message
, Man
at B&Q writes

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

No it doesn't you retard

I admit that I could have actually stated which coil I was on about, but
I expected people to have a bit more of a clue than yourself and
understand that I was on about the fan coil

Relays have coils. Motors have rotor or stator windings (maybe even
both). Learn to use the correct terminolgy and we might get on.

MBQ

On Aug 30, 12:16*pm, Tim Lamb wrote:
In message
, Man
at B&Q writes









On Aug 29, 9:20*am, Tim Lamb wrote:
In message
, Man
at B&Q writes

On Aug 28, 7:43*pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot
water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

Hmm.. I think you know what was meant:-)

No, using the words "relay" and "coil" in the same sentence is very
easily construed as referring only to the relay.

MBQ

"Man at B&Q" wrote:
On Aug 30, 12:16 pm, Tim Lamb wrote:
In message
, Man
at B&Q writes









On Aug 29, 9:20 am, Tim Lamb wrote:
In message
, Man
at B&Q writes

On Aug 28, 7:43 pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot
water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

Hmm.. I think you know what was meant:-)

No, using the words "relay" and "coil" in the same sentence is very
easily construed as referring only to the relay.

MBQ

********. We (and you) knew that he was talking about an inductive load.

Tim

In message
, Man
at B&Q writes
On Aug 30, 8:09*pm, geoff wrote:
In message
, Man
at B&Q writes

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

No it doesn't you retard

I admit that I could have actually stated which coil I was on about, but
I expected people to have a bit more of a clue than yourself and
understand that I was on about the fan coil

Relays have coils. Motors have rotor or stator windings (maybe even
both). Learn to use the correct terminolgy and we might get on.

Not sure I really want to

Pedants who are stupid for the sake of it are not the sort of person I
can be arsed with

I have better things to do with my time, like running a business which
repairs boiler pcbs, for example




--
geoff

On Aug 30, 8:27*pm, Tim+ wrote:
"Man at B&Q" wrote:









On Aug 30, 12:16 pm, Tim Lamb wrote:
In message
, Man
at B&Q writes

On Aug 29, 9:20 am, Tim Lamb wrote:
In message
, Man
at B&Q writes

On Aug 28, 7:43 pm, geoff wrote:
In message ,
writes

the fan motor connector!

I isolated the mains and set to buzzing out the route between line at
the mains LIVE input screw terminal, the relay contacts and the brown
wire (live) on the fan connector (WITH A dvm SET TO AUDIO BUZZER)
revealed that the contacts were now making too light a contact to work.
A bit of adjustment with a fine blade on the live fixed relay contact
soon brought the clearances back into kilter and I now have hot
water again.

I may have to replace that relay in future but I'll see how it goes.

Fan control relay - back EMF of the coil

Doesn't affect the contacts.

Yes it does. Maintains the arc for longer than for a resistive load
would.

Well, "Fan control relay - back EMF of the coil" implies the back EMF
of the relay coil is somehow causing the isue with the contacts. It
dosn't.

Hmm.. I think you know what was meant:-)

No, using the words "relay" and "coil" in the same sentence is very
easily construed as referring only to the relay.

MBQ

********. We (and you) knew that he was talking about an inductive load.

******** to that.

MBQ