Baxi Neta-Tec Combi woes

[Fredxxx]

Whilst newer boilers might use less gas, their running costs seem to
offset any saving!

Not sure if anyone here can help, but I get lock-out and an E-128 error
that implies that there have been a dozen flame failures.

Symptoms are that the boiler fires up nicely, but I can see/hear the gas
rate is changing over time (undulating) and never ramps up to max, even
though CH water is cold.

Subsequently the boiler cycles between running, purging and relighting
such that the water temperature never gets above 50-60 degs.

All the menu accessible temperature sensors seem spot on, the ionising
electrode has been gently cleaned, though not with any abrasive.

Any ideas?

[Fredxxx]

I was hoping that someone somewhere might have some experience of these
boilers.

The only thing I can find out on forums, is that the gas valve is prone
to fail, but I don't think that can cause the undulating gas flow I'm
getting!

[Andrew Gabriel]

In article <leecjd$smn$2...@dont-email.me>,

It could be if it's involved in modulating the burner.
I don't know if it is on a Baxi.
Some gas valves modulate by varying the coil voltage, whereas with
others the coil is just on/off, and modulation is done by pressure
feedback to the gas valve from a Venturi in the gas/air path which
is indirectly driven from the fan speed. There are probably other
schemes too.

How long since the boiler was serviced?

You might have got more help if you gave the model number, and even
a pointer to the installation/servicing instructions online.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[Fredxxx]

Many thanks.

The installation manual is split into 2 parts

http://www.baxi.co.uk/documents/neta-tec-ga-installation-instructions-1-31.pdf

http://www.baxi.co.uk/documents/neta-tec-ga-installation-instructions-32-56.pdf
The boiler is a Baxi Neta-Tec Combi 24 GA

I have no idea how the modulation is done, though there are a number of
people complaining of faulty gas valves. The gas valve does looks
rather small.

To my knowledge the boiler was installed less than a year ago, or
serviced less than a year ago. I shall try and find out more from the
previous owners just that I don't have any paperwork.

The servicing aspect looks easy enough, and is just a visual inspection
of the burner and assembly that is easy to remove, with no further
dismantling. I have to say it all looks very clean.

[Fredxxx]

On 24/02/2014 13:47, Andrew Gabriel wrote:

Thanks to Andrew for his post.

A Baxi engineer came out as it was under warranty.

He updated the firmware, recalibrated the boiler as per procedure in a
document I have found, then changed the flame sensor (probably
unnecessarily) checked the flue gas was in the right ball park region,
and left! He commented that gas valves do "drift".

I now have a fully working boiler, still a Baxi though!

[ray.al...@mail.com]

That's good, I was going to suggest a blog that someone made which lists error faults on boilers and what can be done about them :

http://heatingandboilers.wordpress.com/

[Geo]

5 posts today in this group from this spammer for STL -
"amazed at how much I'd ended-up saving "
"blog that someone made"
"rang some local North West based firms"

- I smell a rat.

[fred]

In article <k2npdadvup0ktm4nc...@4ax.com>, Geo
<nhhu...@dea.spamcon.org> writes

I don't usually bother with these tossers but I think a special example
is due in this case:

https://wordpress.com/abuse/

"This wordpress pseudoblogger is spamming his wp address across the
usenet group uk.d-i-y, generally on long expired threads without a
genuine wish to help the DIY community and contrary to the spirit and
non-advertising charter of the group."

--
fred
it's a ba-na-na . . . .

[concernedo...@gmail.com]

same problem today changed the changover valve on bottles at moment,problem solved