My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

Razoo wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

My parts list which dates from about 1990 has:

Pressure switch - Honeywell C6065A1192
P.I.L. Part No 642220
G.C. Part No 378036

No idea what the rating is. I bought one last year for my boiler but
memory being is I can't remember what I did with the old one which was
apparently not faulty. I think I trimmed the ends of the pipe to get a
good seal.

FWIW I got my bits from keeptheheaton.com and would use them again if
more parts are needed.

Is there anything else I should check on the boiler?

Not that I can think of atm but with a memory like mine that is not to
say there isn't. We had a thread going last year (or possibly a bit
earlier) when I was trying to sort out my boiler. There might be
something useful in that if you can find it with such a vague direction.

Roger Chapman wrote:

snip

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

My parts list which dates from about 1990 has:

Pressure switch - Honeywell C6065A1192
P.I.L. Part No 642220
G.C. Part No 378036

No idea what the rating is. I bought one last year for my boiler but
memory being is I can't remember what I did with the old one which was
apparently not faulty. I think I trimmed the ends of the pipe to get a
good seal.

FWIW I got my bits from keeptheheaton.com and would use them again if
more parts are needed.

Is there anything else I should check on the boiler?

Not that I can think of atm but with a memory like mine that is not to
say there isn't. We had a thread going last year (or possibly a bit
earlier) when I was trying to sort out my boiler. There might be
something useful in that if you can find it with such a vague direction.

Afterthought

The problem solving chart suggests you are on the right lines unless
there are sparks occurring elsewhere. Only only other check is is there
240 volts between T2 and T4 on the electronic control. If the answer is
yes you need to replace the electronic control.

In message , Razoo
writes
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?


There are different makes and models of APSs. Phone up a central heating
merchant and ask, they should know.

The pressure rating is set for a particular boiler, you can't just put a
different one in
You should not adjust the pressure rating of the APS unless you really
do know what you are doing. From the questions you are asking and the
way you are approaching the problem I don't think that you do

Just in case you are unclear as to what I am saying, don't put an
incorrect APS in and try to adjust the pressure. That you ask says to me
that you have moved outside your competence zone into potentially
dangerous territory


You don't say what you have done to check the APS, so here we go, from
the start to check out your APS

First easy check is to (gently) suck or blow (depending on which tube)
down one of the tubes to the APS and see if that causes the boiler to
fire up. If it does, then the fan is not causing the APS to transfer
(which may or may not be a fan problem - could be a blockage or
something somewhere

Now to check the APS itself. Power down the boiler and take the molex
connector off the pcb (always measure from the pcb , then you are
testing the loom as well)
Zero the probes of your multimeter by touching them together and
registering the resistance. Check the Normally closed to common
resistance of the APS at the molex connector, it should not be more than
a couple of ohms (the connections are stamped on the microswitch)

Now, suck or blow on one of the tubes to operate the APS and kink the
tube so that the air cannot escape - this a - checks for a rupture in
the diaphragm and b - makes it easier to check the normally open to
common resistance which should also be a couple of ohms or less


--
geoff

On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

have you checked to see if the overheat stat has tripped?.... its on
the underside of the boiler covered by an obvious plastic flap!

In message
,
Tommy writes
On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

have you checked to see if the overheat stat has tripped?.... its on
the underside of the boiler covered by an obvious plastic flap!

If it had, the fan would not be running, would it ?

--
geoff

On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

second thoughts

Sounds like the dps venturi may be restricted or a flue problem, check
the flue terminal could be overgrown plants if not get the boiler
serviced.

In message
,
Tommy writes
On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

second thoughts

Sounds like the dps venturi may be restricted or a flue problem, check
the flue terminal could be overgrown plants if not get the boiler
serviced.

Shall we try and solve this in a logical manner ...

or like a headless chicken

Please leave this to me, I'm fairly good at this


--
geoff

On 6 Oct, 00:24, geoff wrote:
In message
,
Tommy writes





On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure switch is
rated 0.7mbar, whilst the replacement air pressure switch I've been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

second thoughts

Sounds like the dps venturi may be restricted or a flue problem, check
the flue terminal could be overgrown plants if not get the boiler
serviced.

Shall we try and solve this in a logical manner ...

or like a headless chicken

Please leave this to me, I'm fairly good at this

--
geoff- Hide quoted text -

- Show quoted text -

Its all yours chicken

In message
,
Tommy writes
On 6 Oct, 00:24, geoff wrote:
In message
,
Tommy writes





On 5 Oct, 08:51, "Razoo" wrote:
My Potterton Profile 60e has stopped working. There is no pilot light or
ignition cycle.

I have established that the air pressure switch is not operating, although
the fan is running normally. *If I simulate the operation of the air
pressure switch, the boiler ignites correctly.

I have checked the flexible tubes to the air pressure switch and
they appear
OK with no obvious splits or leaks. *The in-line restrictor (pneumatic
inductor) is not blocked. The mechanical operation of the air pressure
switch itself does seem to be a bit hesitant and 'sticky'.

I intend to replace the air pressure switch and also the two
flexible pipes.
The existing air pressure switch (which itself might already be a
replacement) doesn't look exactly like the pictures of the alleged correct
pressure switch on the Internet. *The microswitch is orientated
differently - mine has the terminals at 12 O'clock when the
pressure switch
is mounted (mounting screws at 9 O'clock, pneumatic connections at 3
O'clock). *More significantly, the existing (faulty) air pressure
switch is
rated 0.7mbar, whilst the replacement air pressure switch I've
been offered
is rated 0.35mbar.

Can anyone tell me the correct pressure rating and part number for a
Potterton Profile 60e air pressure switch?

Is there anything else I should check on the boiler?

Thanks,

Razoo

second thoughts

Sounds like the dps venturi may be restricted or a flue problem, check
the flue terminal could be overgrown plants if not get the boiler
serviced.

Shall we try and solve this in a logical manner ...

or like a headless chicken

Please leave this to me, I'm fairly good at this

--
geoff- Hide quoted text -

- Show quoted text -

Its all yours chicken

Good - **** off then

--
geoff

Tommy wrote:

have you checked to see if the overheat stat has tripped?.... its on
the underside of the boiler covered by an obvious plastic flap!

Not on my Profile. The only thing under an obvious plastic flap is the
securing screw for the removable base. Vision of the OP opening a flap
and having endless trouble trying to press up a solid steel screw. :-)

Geoff wrote:

There are different makes and models of APSs. Phone up a central
heating merchant and ask, they should know.

Yes, they should.... unless you get spotty yoof on work experience.

The pressure rating is set for a particular boiler, you can't just put a
different one in.

Agreed, and that's exactly my point! I had searched for a replacement APS
on the Web and noticed that the ones offered as correct for my Potterton
Profile 60e were rated 0.35mbar. The one I had removed was rated 0.7mbar.
Obviously one had to be the wrong rating - but which one? The Potterton
documentation is very basic with no real technical content, so that's why I
asked the question on this ng.

A visit to Interpart yesterday established that the correct APS rating is
0.35mbar, which means the wrong APS had been fitted previously (not by me,
because all work up until now had been carried out under a maintenance
contract).

You should not adjust the pressure rating of the APS unless
you really do know what you are doing.

I do have the facilities at work to calibrate these pressure switches, but I
see no need to at the moment.

From the questions you are asking and the way you are approaching
the problem I don't think that you do.

Well thanks for the vote of confidence!

Just in case you are unclear as to what I am saying, don't put an
incorrect APS in and try to adjust the pressure.

Obviously not, hence my question to establish what the correct APS rating
should be.

That you ask says to me that you have moved outside your
competence zone into potentially dangerous territory.

Not so! I was trying to avoid *exactly* that error by establishing first
what the correct APS rating should be.

You don't say what you have done to check the APS, so here we go, from the
start to check out your APS

First easy check is to (gently) suck or blow (depending on which tube)
down one of the tubes to the APS and see if that causes the boiler to fire
up. If it does, then the fan is not causing the APS to transfer (which may
or may not be a fan problem - could be a blockage or something somewhere

Did that.

Now to check the APS itself. Power down the boiler and take the molex
connector off the pcb (always measure from the pcb , then you are testing
the loom as well)
Zero the probes of your multimeter by touching them together and
registering the resistance. Check the Normally closed to common resistance
of the APS at the molex connector, it should not be more than a couple of
ohms (the connections are stamped on the microswitch)

Now, suck or blow on one of the tubes to operate the APS and kink the tube
so that the air cannot escape - this a - checks for a rupture in the
diaphragm and b - makes it easier to check the normally open to common
resistance which should also be a couple of ohms or less

Yes, I did all those checks and the APS was operating correctly, although as
I said in my op, the mechanical operation of the air pressure switch itself
did seem to be a bit hesitant and 'sticky'.

However, all this is irrelevant as I have now established that the existing
APS (0.7mbar) is the wrong rating for the boiler. I have therefore
purchased a new APS of the correct rating (0.35mbar, Part No. 642223).

Rather annoyingly, Interpart could not supply new flexible tubes, so I've
now got a new APS, mounting bracket, screws and anti-kink springs - and no
new tubes!

I fitted the new APS yesterday evening, but still have a problem - see my
latest post. in this thread.

Thanks for your detailed input.
--
Razoo

I have replaced the incorrect 0.7mbar APS with a new 0.35mbar APS.

Although the fan runs, the APS is still not switching over.

The APS sensing tubes and the flue are completely clear, and gently sucking
on the LP tube causes the APS to change state.

I cannot find any air leaks in the APS sensing tubes (although I am going to
test for leaks again tonight, just to be sure).

The boiler cover seals are in good condition.

I'm now wondering if the fan, although running, might not be running at its
normal rate. It seems to be running OK, but I have no benchmark to compare
it with.

Is the performance of these fans prone to dropping off?

Is there anything else that may affect operation of the APS?

Thanks,
--
Razoo

Roger Chapman wrote:

My parts list which dates from about 1990 has:

Pressure switch - Honeywell C6065A1192
P.I.L. Part No 642220
G.C. Part No 378036

Thanks Roger - the APS I have just bought is Part No. 642223 (0.35mbar)
--
Razoo

Tommy wrote:

Have you checked to see if the overheat stat has tripped?....
its on the underside of the boiler covered by an obvious
plastic flap!

The reset was checked early on and it isn't tripped.
--
Razoo

Razoo wrote:
Roger Chapman wrote:
My parts list which dates from about 1990 has:

Pressure switch - Honeywell C6065A1192
P.I.L. Part No 642220
G.C. Part No 378036

Thanks Roger - the APS I have just bought is Part No. 642223 (0.35mbar)

Says 642220 above, not 642223. Are you sure you have the right pressure
switch?

Roger Chapman wrote:

I wrote:
Thanks Roger - the APS I have just bought is Part No. 642223
(0.35mbar)

Says 642220 above, not 642223. Are you sure you have the
right pressure switch?

I'm as sure as I can be in the absence of any useful technical information
from Potterton.

Interparts checked on their database and in a manual and confirmed Part No.
642223 as correct.

I researched the APS from two online suppliers and they were both offering
the 642223, 0.35mbar APS as the correct unit for Potterton Profile 60e.

Finally, an eBay seller is also offering this same APS for the 60e.

If it's not right, a lot of people have got it wrong!
--
Razoo

"Razoo" wrote in message
...
Roger Chapman wrote:

I wrote:
Thanks Roger - the APS I have just bought is Part No. 642223
(0.35mbar)

Says 642220 above, not 642223. Are you sure you have the
right pressure switch?

I'm as sure as I can be in the absence of any useful technical information
from Potterton.

Interparts checked on their database and in a manual and confirmed Part
No.
642223 as correct.

I researched the APS from two online suppliers and they were both offering
the 642223, 0.35mbar APS as the correct unit for Potterton Profile 60e.

Finally, an eBay seller is also offering this same APS for the 60e.

If it's not right, a lot of people have got it wrong!
--
Part no 642220 is for Profile Prima 60e Gc no 41 605 73

You do have a Profile 60e Gc no 41 605 42?

Heliotrope Smith wrote:

Part no 642220 is for Profile Prima 60e Gc no 41 605 73

You do have a Profile 60e Gc no 41 605 42?

Yes, Profile 60e (not Prima), GC No. 41-605-42
--
Razoo

Razoo wrote:
Heliotrope Smith wrote:
Part no 642220 is for Profile Prima 60e Gc no 41 605 73

You do have a Profile 60e Gc no 41 605 42?

Yes, Profile 60e (not Prima), GC No. 41-605-42

In which case I may have inadvertently tried to mislead you, sorry for
that. I have a Profile Prima but I have always understood, perhaps
incorrectly, that they were essentially the same boiler, the difference
being the presence or absence of separate connections for the domestic
hot water circuit.

The sales leaflet I obtained prior to purchase was for "The Profile
Range". I had temporarily at least forgotten that when I went out to buy
my boiler back in 1991 I was persuaded that I didn't need separate
connections for the DHW as I was planning on a fully pumped system
unlike the then existing system with gravity DHW.

Incidentally I have now found the possibly defunct pressure switch I
replaced last year. The label says P = 0.4mbar Max. 6mbar.

Roger Chapman wrote:

I wrote:

Yes, Profile 60e (not Prima), GC No. 41-605-42

In which case I may have inadvertently tried to mislead you, sorry for
that. I have a Profile Prima but I have always understood, perhaps
incorrectly, that they were essentially the same boiler, the difference
being the presence or absence of separate connections for the domestic hot
water circuit.

The sales leaflet I obtained prior to purchase was for "The Profile
Range". I had temporarily at least forgotten that when I went out to buy
my boiler back in 1991 I was persuaded that I didn't need separate
connections for the DHW as I was planning on a fully pumped system unlike
the then existing system with gravity DHW.

Incidentally I have now found the possibly defunct pressure switch I
replaced last year. The label says P = 0.4mbar Max. 6mbar.

Hi Roger,

No problem re. APS Part No. - thanks for your input.
--
Razoo

In message , Razoo
writes
I have replaced the incorrect 0.7mbar APS with a new 0.35mbar APS.

Although the fan runs, the APS is still not switching over.

I just knew you were going to say that

Something told me


The APS sensing tubes and the flue are completely clear, and gently sucking
on the LP tube causes the APS to change state.

So the problem can absolutely be tied down to lack of differential
pressure at the diaphragm

Profile 60 fans can drop off in power, but its not very common. On the
Netaheat (the Profile's predecessor), there is a bulkhead connector with
a fine hole in it (to avoid wind affecting the pressure at the APS.
Check if your boiler has one. If it does, this can get crudded up and
prevent the APS from seeing the correct pressure

Other things which can cause problems are (as someone else said) a
blockage in the flue, clogged heat exchanger fins, lack of integrity of
the case seal (you might not have noticed that rusty hole)

If you are sure you have checked all of these, then if you ring tomorrow
between 9 and 10 am, and ask for John, he's worked on profiles and such
for about 2000 years on the gas board and there is very little he
doesn't know about profiles. After 10, he should be off doing a delivery
run. I should be there after about 10am

01923 229224


If you do think its the fan I do an exchange one for £45 ++



I cannot find any air leaks in the APS sensing tubes (although I am going to
test for leaks again tonight, just to be sure).

The boiler cover seals are in good condition.

I'm now wondering if the fan, although running, might not be running at its
normal rate. It seems to be running OK, but I have no benchmark to compare
it with.

Is the performance of these fans prone to dropping off?

Is there anything else that may affect operation of the APS?

Thanks,

--
geoff

On 6 Oct, 11:37, "Razoo" wrote:
Last question first!!

Is there anything else that may affect operation of the APS?

Relying on memory here, the aps is below the combustion chamber within
the grey plasic boiler housing & the aps tubes connect to metal pipes
with 1 pipe travelling up to the fan where it is connected to it with
another white rubber tube.
Clear the metal tube & also especially the plastic venturi connecting
the tube to the fan.....only if gas-safe registered though.

I have replaced the incorrect 0.7mbar APS with a new 0.35mbar APS.

Are you sure you connected the wires to the correct terminals?

Although the fan runs, the APS is still not switching over.

The APS sensing tubes and the flue are completely clear, and gently sucking
on the LP tube causes the APS to change state.


By change state do you mean the ignition sequence begins?
if yes
Does the burner light? if no its your gas valve

I cannot find any air leaks in the APS sensing tubes (although I am going to
test for leaks again tonight, just to be sure).

forget that

The boiler cover seals are in good condition.

I'm now wondering if the fan, although running, might not be running at its
normal rate. *It seems to be running OK, but I have no benchmark to compare
it with.

Is the performance of these fans prone to dropping off?

Yes but not likely

Is there anything else that may affect operation of the APS?

In message
,
Tommy writes
On 6 Oct, 11:37, "Razoo" wrote:
Last question first!!

Is there anything else that may affect operation of the APS?

Relying on memory here, the aps is below the combustion chamber within
the grey plasic boiler housing & the aps tubes connect to metal pipes
with 1 pipe travelling up to the fan where it is connected to it with
another white rubber tube.
Clear the metal tube & also especially the plastic venturi connecting
the tube to the fan.....only if gas-safe registered though.

Aah a 'kin feral fitter

so why the stupid reply regarding the OH reset ?



I have replaced the incorrect 0.7mbar APS with a new 0.35mbar APS.

Are you sure you connected the wires to the correct terminals?

Although the fan runs, the APS is still not switching over.

The APS sensing tubes and the flue are completely clear, and gently sucking
on the LP tube causes the APS to change state.


By change state do you mean the ignition sequence begins?
if yes
Does the burner light? if no its your gas valve

I cannot find any air leaks in the APS sensing tubes (although I am going to
test for leaks again tonight, just to be sure).

forget that

The boiler cover seals are in good condition.

I'm now wondering if the fan, although running, might not be running at its
normal rate. *It seems to be running OK, but I have no benchmark to compare
it with.

Is the performance of these fans prone to dropping off?

Yes but not likely

Aha - we is in agreement

Is there anything else that may affect operation of the APS?


The APS is purely a membrane which moves under the action of the
differential pressure caused by the fan. This membrane moves a
microswitch from the NC to the NO position

that's it

--
geoff

Geoff wrote:

I wrote:

I have replaced the incorrect 0.7mbar APS with a new
0.35mbar APS.

Although the fan runs, the APS is still not switching over.

I just knew you were going to say that

I just knew that would be the outcome. I guess we both have a close
affinity with Mr Sod and his Law ;-)

The APS sensing tubes and the flue are completely clear, and
gently sucking on the LP tube causes the APS to change state.

So the problem can absolutely be tied down to lack of
differential pressure at the diaphragm

Yes, it can.

Profile 60 fans can drop off in power, but its not very common.

Well, I have now found the fault, and it is the fan.

I took the fan out and ran it on the bench. I could then see it had a
tendency to run seemingly well for a short while, and then hesitate
slightly, before picking up again. I guess in reality the fan was running
significantly slower than its normal operating speed, resulting in reduced
airflow (and consequently the lack of differential pressure across the APS).

I stripped the fan down and found that the armature sleeve bearings were dry
and binding, especially the front bearing.

It's a Sifan fan (Model: 409583) with spherical, self-aligning sleeve
bearings bedded in Permawick. The Permawick has completely dried out.

If the bearings had been fitted with the more common oil-soaked felts, I
could have had the fan up an running again in no time. But getting hold of
some Permawick quickly - now there's a challenge! I guess I might be making
up some felt pads tonight.

If you are sure you have checked all of these, then if you ring tomorrow
between 9 and 10 am, and ask for John, he's worked on profiles and such
for about 2000 years on the gas board and there is very little he doesn't
know about profiles. After 10, he should be off doing a delivery run. I
should be there after about 10am

Thanks, that's kind of you to offer this service.

If you do think its the fan I do an exchange one for £45 ++

That's a reasonable price. The price I've been quoted for a new fan spoils
the look of £100.

I intend to have another go at the fan bearings tonight. I'll report back.
--
Razoo

Tommy wrote:

I wrote:

Is there anything else that may affect operation of the APS?

Relying on memory here, the aps is below the combustion chamber within
the grey plastic boiler housing & the aps tubes connect to metal pipes
with 1 pipe travelling up to the fan where it is connected to it with
another white rubber tube.

The APS is located where you say. The two metal APS tubes travel up the
inside left of the boiler casing, and protrude into the intake air plenum.
Both metal tubes are then connected by flexible silicone rubber tubes to two
metal stub tubes protruding from the exhaust flue elbow.

Clear the metal tube & also especially the plastic venturi connecting
the tube to the fan.....only if gas-safe registered though.

There's no direct 'tube to fan' connection (see above).

I have replaced the incorrect 0.7mbar APS with a new 0.35mbar APS.

Are you sure you connected the wires to the correct terminals?

Absolutely! The boiler runs fine if I manually operate the APS.

Although the fan runs, the APS is still not switching over.

The APS sensing tubes and the flue are completely clear, and gently
sucking
on the LP tube causes the APS to change state.

By change state do you mean the ignition sequence begins?

No, I mean that the APS microswitch contacts operated by the APS diaphragm
change over (the NC contact opens and the NO contact closes).

Is the performance of these fans prone to dropping off?

Yes but not likely

It turns out that the fan is faulty (partially seized armature sleeve
bearings, causing the fan to run slow).
--
Razoo

In message , Razoo
writes
Geoff wrote:

I wrote:

I have replaced the incorrect 0.7mbar APS with a new
0.35mbar APS.

Although the fan runs, the APS is still not switching over.

I just knew you were going to say that

I just knew that would be the outcome. I guess we both have a close
affinity with Mr Sod and his Law ;-)

The APS sensing tubes and the flue are completely clear, and
gently sucking on the LP tube causes the APS to change state.

So the problem can absolutely be tied down to lack of
differential pressure at the diaphragm

Yes, it can.

Profile 60 fans can drop off in power, but its not very common.

Well, I have now found the fault, and it is the fan.

I took the fan out and ran it on the bench. I could then see it had a
tendency to run seemingly well for a short while, and then hesitate
slightly, before picking up again. I guess in reality the fan was running
significantly slower than its normal operating speed, resulting in reduced
airflow (and consequently the lack of differential pressure across the APS).

I stripped the fan down and found that the armature sleeve bearings were dry
and binding, especially the front bearing.

They normally squeal like buggery when they get to this stage - which is
why I ruled out running slow


It's a Sifan fan (Model: 409583) with spherical, self-aligning sleeve
bearings bedded in Permawick. The Permawick has completely dried out.

If the bearings had been fitted with the more common oil-soaked felts, I
could have had the fan up an running again in no time. But getting hold of
some Permawick quickly - now there's a challenge! I guess I might be making
up some felt pads tonight.

Where are you ?

I think I have some profile motors waiting for the scrappie to pick up


If you are sure you have checked all of these, then if you ring tomorrow
between 9 and 10 am, and ask for John, he's worked on profiles and such
for about 2000 years on the gas board and there is very little he doesn't
know about profiles. After 10, he should be off doing a delivery run. I
should be there after about 10am

Thanks, that's kind of you to offer this service.

If you do think its the fan I do an exchange one for £45 ++

That's a reasonable price. The price I've been quoted for a new fan spoils
the look of £100.

I intend to have another go at the fan bearings tonight. I'll report back.

--
geoff

Geoff wrote:

I wrote:

Well, I have now found the fault, and it is the fan.

I stripped the fan down and found that the armature sleeve
bearings were dry and binding, especially the front bearing.

They normally squeal like buggery when they get to this stage...

Unfortunately not a squeak from this one, which is a pity because the
'scream of a tortured bearing' would have instantly identified the problem
and saved a lot of time and effort.

It's a Sifan fan (Model: 409583) with spherical, self-aligning
sleeve bearings bedded in Permawick. The Permawick has
completely dried out.

If the bearings had been fitted with the more common oil-soaked
felts, I could have had the fan up an running again in no time. But
getting hold of some Permawick quickly - now there's a challenge!
I guess I might be making up some felt pads tonight.

I think I have some profile motors waiting for the scrappie to pick up

Thanks for the offer. However, the boiler is repaired and running fine now.

Sometimes the Alpha female of the group gets fed up with waiting and pulls
rank ;-)

Rather than go any longer without heating, a new fan was purchased yesterday
afternoon (£71 + VAT) and fitted yesterday evening.

I couldn't find a source of Permawick in the UK.

I will probably repair the old fan at my leisure and keep it as a spare.

Thanks for all your help and advice.
--
Razoo

In message , Razoo
writes
Geoff wrote:

I wrote:

Well, I have now found the fault, and it is the fan.

I stripped the fan down and found that the armature sleeve
bearings were dry and binding, especially the front bearing.

They normally squeal like buggery when they get to this stage...

Unfortunately not a squeak from this one, which is a pity because the
'scream of a tortured bearing' would have instantly identified the problem
and saved a lot of time and effort.

It's a Sifan fan (Model: 409583) with spherical, self-aligning
sleeve bearings bedded in Permawick. The Permawick has
completely dried out.

If the bearings had been fitted with the more common oil-soaked
felts, I could have had the fan up an running again in no time. But
getting hold of some Permawick quickly - now there's a challenge!
I guess I might be making up some felt pads tonight.

I think I have some profile motors waiting for the scrappie to pick up

Thanks for the offer. However, the boiler is repaired and running fine now.

Sometimes the Alpha female of the group gets fed up with waiting and pulls
rank ;-)

Rather than go any longer without heating, a new fan was purchased yesterday
afternoon (£71 + VAT) and fitted yesterday evening.

I couldn't find a source of Permawick in the UK.

You just turned it down, didn't you

--
geoff

Geoff wrote:

You just turned it down, didn't you

Turned what down?
--
Razoo