Andrew Gabriel wrote:
In article ,
"JJJ" writes:
A plumber just told me that you're lucky if you get more than 10 years out
of a condensing boiler - because of their complexity and the fact that the
condensate rots them from the inside out...

is he right?

I suspect so. The earlier ones didn't last that long,
mainly failures due to corrosion. Current ones should be
better in this respect.

The high tech microprocessor/microcontroller boards used
in them won't be able able to be made in 10 years time
when I would expect many to fail. Most of the components
will be long obsolete and no one will redesign a board to
use modern components just for the spares market. The life
of the units will be limited by the quantity of up-front
spares manufacturers stock, and it really isn't in their
interests to do this. (and what Geoff gets working again.)

It's pretty much at the point that this could almost be irrelevant.
You design a generic board, with plenty of sensor interfaces, relay
outputs and stuff.
You then plug this into a board with connectors for the original
plugs, and your generic board.

This might be a bit more expensive for OEM, but should be fine for
spares.

The interface board connects up some connectors that are mandatory, for
example, if it has an overheat stat that should shut off all bar the
pump, that's hardwired.
Everything else is done in software, loading a profile of the correct
boiler.

In article ,
Ian Stirling writes:
Andrew Gabriel wrote:
In article ,
"JJJ" writes:
A plumber just told me that you're lucky if you get more than 10 years out
of a condensing boiler - because of their complexity and the fact that the
condensate rots them from the inside out...

is he right?

I suspect so. The earlier ones didn't last that long,
mainly failures due to corrosion. Current ones should be
better in this respect.

The high tech microprocessor/microcontroller boards used
in them won't be able able to be made in 10 years time
when I would expect many to fail. Most of the components
will be long obsolete and no one will redesign a board to
use modern components just for the spares market. The life
of the units will be limited by the quantity of up-front
spares manufacturers stock, and it really isn't in their
interests to do this. (and what Geoff gets working again.)

It's pretty much at the point that this could almost be irrelevant.
You design a generic board, with plenty of sensor interfaces, relay
outputs and stuff.
You then plug this into a board with connectors for the original
plugs, and your generic board.

This might be a bit more expensive for OEM, but should be fine for
spares.

Who is going to go to the effort of working out the
programming though? Without the manufacturer's original
design data (such as graphs plotting premix fan speed
against gas valve proportional control), you can't do it,
except by trial and error. You would never get GC approval
for something like that.

The interface board connects up some connectors that are mandatory, for
example, if it has an overheat stat that should shut off all bar the
pump, that's hardwired.
Everything else is done in software, loading a profile of the correct
boiler.

If it reached the point where most boiler manufacturers
outsourced the microcontroller control aspects to one of
a limited number of companies or bought off-the-shelf
solutions from a small number of companies specialising
in this area, then this might just happen.

For example, does Keston use the control boards for their
C25 in the larger model boilers? Does anyone else use the
same control boards? (Keston doesn't appear to make them
themselves, but I don't know how generic a part they are.)
There are two sizable boards stuffed full of micro-electronics
in these units. They operate in the heat inside the boiler
casing, and they are under one end of the heat exchanger
where they could get wet if it leaked (there's a plastic
shroud, but I would not bet it would save them). I notice the
C25 does seem to have what looks like an unused additional
input for a lockout cause which isn't connected to anything
on the C25. Maybe something used by a different range, or
just protecting themselves in case they find they have to
add air flow or water flow switch or something silimar in
a product rev.

--
Andrew Gabriel

In message , Andrew Gabriel
writes
In article ,
Ian Stirling writes:
Andrew Gabriel wrote:
In article ,
"JJJ" writes:
A plumber just told me that you're lucky if you get more than 10 years out
of a condensing boiler - because of their complexity and the fact that the
condensate rots them from the inside out...

is he right?

I suspect so. The earlier ones didn't last that long,
mainly failures due to corrosion. Current ones should be
better in this respect.

The high tech microprocessor/microcontroller boards used
in them won't be able able to be made in 10 years time
when I would expect many to fail. Most of the components
will be long obsolete and no one will redesign a board to
use modern components just for the spares market. The life
of the units will be limited by the quantity of up-front
spares manufacturers stock, and it really isn't in their
interests to do this. (and what Geoff gets working again.)

It's pretty much at the point that this could almost be irrelevant.
You design a generic board, with plenty of sensor interfaces, relay
outputs and stuff.
You then plug this into a board with connectors for the original
plugs, and your generic board.

This might be a bit more expensive for OEM, but should be fine for
spares.

Who is going to go to the effort of working out the
programming though? Without the manufacturer's original
design data (such as graphs plotting premix fan speed
against gas valve proportional control), you can't do it,
except by trial and error. You would never get GC approval
for something like that.

The interface board connects up some connectors that are mandatory, for
example, if it has an overheat stat that should shut off all bar the
pump, that's hardwired.
Everything else is done in software, loading a profile of the correct
boiler.

If it reached the point where most boiler manufacturers
outsourced the microcontroller control aspects to one of
a limited number of companies or bought off-the-shelf
solutions from a small number of companies specialising
in this area, then this might just happen.

No way ...

They'd all have proprietary software burned in them, which the boiler
manufacturers would hold the copyright on


The information contained in this post
may not be published in, or used by
http://www.diyprojects.info

--
geoff

In article ,
raden writes:
In message , Andrew Gabriel
writes

If it reached the point where most boiler manufacturers
outsourced the microcontroller control aspects to one of
a limited number of companies or bought off-the-shelf
solutions from a small number of companies specialising
in this area, then this might just happen.

No way ...

They'd all have proprietary software burned in them, which the boiler
manufacturers would hold the copyright on

Yes, wasn't a serious suggestion.

If you consider a more expensive item which you expect to last
a lot longer than 10 years, this issue is a real problem.
Some 10+ years ago when I was working on System X, the components
used in that were going obsolete at the rate of around 2 per week
IIRC. You have to maintain a redesign team in that case, just so you
can carry on making line cards and other parts, for a system which
has a design life of decades.

--
Andrew Gabriel
Consultant Software Engineer

In message , Ian
Stirling writes
Andrew Gabriel wrote:
In article ,
"JJJ" writes:
A plumber just told me that you're lucky if you get more than 10 years out
of a condensing boiler - because of their complexity and the fact that the
condensate rots them from the inside out...

is he right?

I suspect so. The earlier ones didn't last that long,
mainly failures due to corrosion. Current ones should be
better in this respect.

The high tech microprocessor/microcontroller boards used
in them won't be able able to be made in 10 years time
when I would expect many to fail. Most of the components
will be long obsolete and no one will redesign a board to
use modern components just for the spares market. The life
of the units will be limited by the quantity of up-front
spares manufacturers stock, and it really isn't in their
interests to do this. (and what Geoff gets working again.)

It's pretty much at the point that this could almost be irrelevant.
You design a generic board, with plenty of sensor interfaces, relay
outputs and stuff.
You then plug this into a board with connectors for the original
plugs, and your generic board.

This might be a bit more expensive for OEM, but should be fine for
spares.

The interface board connects up some connectors that are mandatory, for
example, if it has an overheat stat that should shut off all bar the
pump, that's hardwired.
Everything else is done in software, loading a profile of the correct
boiler.

Great in theory, but it just doesn't happen. The closest to a "generic"
board anyone seems to have got is the Honeywell sequence boards which
fit directly onto gas valves, but even then none of them are quite the
same and there is the rival Italian company SIT who are in competition

You only have to look back a few years when Glowworm had (still have) 6
pcbs which are identical in operation and totally pin compatible, all
very different in design.

While I've often wondered why, and sometimes thought of designing a
generic boiler control PCB, manufacturers are showing no signs of
unifying at all or having any intention of doing so


The information contained in this post
may not be published in, or used by
http://www.diyprojects.info

--
geoff

On Wed, 20 Oct 2004 20:45:57 GMT, raden wrote:



While I've often wondered why, and sometimes thought of designing a
generic boiler control PCB, manufacturers are showing no signs of
unifying at all or having any intention of doing so


There is/has been an "open standard" via a manufacturer consortium in
Holland to attempt to produce a common control interface between room
and water themostats and controls and single or multiple boilers,
basically to provide something better than coarse on/off control via
PWM.

I can't find the link for the moment, but a few of the well known
manufacturers had joined it. IIRC though, little had changed on the
site since about 2000 so it has probably gone the way of most
manufacturer consortia...........


..andy

To email, substitute .nospam with .gl

You only have to look back a few years when
Glowworm had (still have) 6 pcbs which are
identical in operation and totally pin compatible, all
very different in design.

I assume these are all different sizes, and prices. So it is probably worth
using the cheapest of these boards,providing you can get a fixing for the
board.


While I've often wondered why, and sometimes thought of designing a
generic boiler control PCB, manufacturers are showing no signs of
unifying at all or having any intention of doing so


The information contained in this post
may not be published in, or used by
http://www.diyprojects.info

--
geoff

In message , IMM writes


You only have to look back a few years when
Glowworm had (still have) 6 pcbs which are
identical in operation and totally pin compatible, all
very different in design.

I assume these are all different sizes, and prices.

No, exactly the same size, even down to the positioning of the stand-off
holes


So it is probably worth
using the cheapest of these boards,providing you can get a fixing for the
board.

Well you of all people (cough) should know that doing that would lay you
right open for installing the wrong pcb

The information contained in this post
may not be published in, or used by
http://www.diyprojects.info



--
geoff

"raden" wrote in message
...
In message , IMM writes


You only have to look back a few years when
Glowworm had (still have) 6 pcbs which are
identical in operation and totally pin compatible, all
very different in design.

I assume these are all different sizes, and prices.

No, exactly the same size, even down to the positioning of the stand-off
holes

So 6 pcbs all the same size, doing the same thing with different opart Nos?
How odd. But I'm sure different prices.

So it is probably worth
using the cheapest of these boards,providing you can get a fixing for the
board.

Well you of all people (cough) should know that doing that would lay you
right open for installing the wrong pcb

But they are all the same according to you, so yiou can't fit the wrong one.

In message , IMM writes

"raden" wrote in message
...
In message , IMM writes


You only have to look back a few years when
Glowworm had (still have) 6 pcbs which are
identical in operation and totally pin compatible, all
very different in design.

I assume these are all different sizes, and prices.

No, exactly the same size, even down to the positioning of the stand-off
holes

So 6 pcbs all the same size, doing the same thing with different opart Nos?
How odd. But I'm sure different prices.

So it is probably worth
using the cheapest of these boards,providing you can get a fixing for the
board.

Well you of all people (cough) should know that doing that would lay you
right open for installing the wrong pcb

But they are all the same according to you, so yiou can't fit the wrong one.

But different part numbers, so no, from an insurance point of view


The information contained in this post
may not be published in, or used by
http://www.diyprojects.info


--
geoff

"raden" wrote in message
...
In message , IMM writes

"raden" wrote in message
...
In message , IMM
writes


You only have to look back a few years when
Glowworm had (still have) 6 pcbs which are
identical in operation and totally pin compatible, all
very different in design.

I assume these are all different sizes, and prices.

No, exactly the same size, even down to the positioning of the
stand-off
holes

So 6 pcbs all the same size, doing the same thing with different opart
Nos?
How odd. But I'm sure different prices.

So it is probably worth
using the cheapest of these boards,providing you can get a fixing for
the
board.

Well you of all people (cough) should know that doing that would lay
you
right open for installing the wrong pcb

But they are all the same according to you, so yiou can't fit the wrong
one.

But different part numbers, so no, from an insurance point of view

But "technically" the same thing.