The oil CH boiler's a Worcester Danesmoor HPJU25OOO. It's nearly 20
years old, and has been 'professionally' serviced annually - and it has
been fairly trouble free.

About 6 months ago, it started locking out - but the local service guy
got it sorted out. Unfortunately, it has started doing it again
(although I've turned its internal thermostat up a bit, and it seems to
be OK at the moment) - and I'm going to call him again tomorrow to have
another look at it.

Anyway, my question really relates to the ignition (which I want to ask
the service guy about, when he comes).

For the past couple of years, I have been aware of the following:

1. While the ignition is sparking, there has been a considerable
increase in interference to the radio. My previous boiler was very bad,
and needed the insertion of a suppressor in the ignition lead. This
boiler used to quiet - but it now seems to have got pretty bad. [I'm
pretty sure that neither the ignition lead nor the igniter have been
changed.]

2. The time the ignition runs for seems excessive long. The ignition
sequence is roughly
- The motor starts - and at the same time, the igniter starts sparking
(as heard on a nearby radio).
- After about 3 seconds, there is a slight click (presumably the oil
valve opening or pump starting).
- After about 5 more seconds, there is a 'whump', and the boiler
ignites. At the same time, the intensity of the interference drops
slightly (presumably the flame is partially shorting the spark-gap).
- The boiler continues to burn as it should, but the ignition spark
(the interference) also continues for typically 30 to 40 seconds.

So has anyone got any advice as to whether this sort of behaviour is
normal? I don't think there is any connection with the lock-out problem,
but it would nice to know if the long ignition duration is typical - and
if there's likely to be any service adjustment to shorten it to
something more sensible.
--
Ian

On Sun, 5 Feb 2017 19:57:23 +0000, Ian Jackson wrote:

1. While the ignition is sparking, there has been a considerable
increase in interference to the radio.

That shouln't happen, pretty sure ours produces no interference at
all.
wanders off to bolier with MF radio tuned to inter station space
maybe a brief "tick".

2. The time the ignition runs for seems excessive long. The ignition
sequence is roughly
- The motor starts - and at the same time, the igniter starts sparking
(as heard on a nearby radio).

Odd. Are you sure the interference is the igniter and not the motor?

- After about 3 seconds, there is a slight click (presumably the oil
valve opening or pump starting).

AFAIK all burners have the pump driven by the fan motor. Click I'd
say if the valve opening but 3 seconds pre-run seems short.

- After about 5 more seconds, there is a 'whump', and the boiler
ignites.

We get clickwhump after about 10 seconds of pre-run.

Ignition should be very quick, might be a weak spark (due to
knackered supression component(s)) and/or bad adjustment and/or
erroded electrodes in relation to the nozzle.

- The boiler continues to burn as it should, but the ignition spark
(the interference) also continues for typically 30 to 40 seconds.

That seems wrong as well. The flame detection should turn the
ignition off once it detects a flame and turn it back on if the flame
fails. Failure to ignite within a few tens of seconds will lead to a
lock-out. Maybe the photocell is sooted up?

I don't think there is any connection with the lock-out problem,

If several things become marginal, weak ignition long time to
ignite, poor flame detection longer time to detection, worn nozzle
bad spray pattern/big droplets hard to ignite, can all add up to a
lockout.

The Riello burner in our bolier has the following sequence:

Power on
Motor/pump runs for 12 seconds
Valve opens
Flame detected?
No
Igniter on
5 seconds elapsed?
No
Goto Flame Detected?
Yes
LOCKOUT, Valve closed, Igniter off, motor off, lockoout
indicator
on
Yes.
Igniter off, Valve open, Motor on
Goto Flame Detected?

--
Cheers
Dave.

On Sun, 5 Feb 2017 19:57:23 +0000, Ian Jackson
wrote:

The oil CH boiler's a Worcester Danesmoor HPJU25OOO. It's nearly 20
years old, and has been 'professionally' serviced annually - and it has
been fairly trouble free.

About 6 months ago, it started locking out - but the local service guy
got it sorted out. Unfortunately, it has started doing it again
(although I've turned its internal thermostat up a bit, and it seems to
be OK at the moment) - and I'm going to call him again tomorrow to have
another look at it.

Anyway, my question really relates to the ignition (which I want to ask
the service guy about, when he comes).

For the past couple of years, I have been aware of the following:

1. While the ignition is sparking, there has been a considerable
increase in interference to the radio. My previous boiler was very bad,
and needed the insertion of a suppressor in the ignition lead. This
boiler used to quiet - but it now seems to have got pretty bad. [I'm
pretty sure that neither the ignition lead nor the igniter have been
changed.]

2. The time the ignition runs for seems excessive long. The ignition
sequence is roughly
- The motor starts - and at the same time, the igniter starts sparking
(as heard on a nearby radio).
- After about 3 seconds, there is a slight click (presumably the oil
valve opening or pump starting).
- After about 5 more seconds, there is a 'whump', and the boiler
ignites. At the same time, the intensity of the interference drops
slightly (presumably the flame is partially shorting the spark-gap).
- The boiler continues to burn as it should, but the ignition spark
(the interference) also continues for typically 30 to 40 seconds.

So has anyone got any advice as to whether this sort of behaviour is
normal? I don't think there is any connection with the lock-out problem,
but it would nice to know if the long ignition duration is typical - and
if there's likely to be any service adjustment to shorten it to
something more sensible.

Hay, I was waxing lyrical about oil boiler QRM in the Smart-meters
thread in URAM.

On Sun, 05 Feb 2017 19:57:23 -0000, Ian Jackson wrote:

The oil CH boiler's a Worcester Danesmoor HPJU25OOO. It's nearly 20
years old, and has been 'professionally' serviced annually - and it has
been fairly trouble free.

About 6 months ago, it started locking out - but the local service guy
got it sorted out. Unfortunately, it has started doing it again
(although I've turned its internal thermostat up a bit, and it seems to
be OK at the moment) - and I'm going to call him again tomorrow to have
another look at it.

Anyway, my question really relates to the ignition (which I want to ask
the service guy about, when he comes).

For the past couple of years, I have been aware of the following:

1. While the ignition is sparking, there has been a considerable
increase in interference to the radio.

People still use analogue radio?

And a pilot light is better than lighting the bloody thing each time.

--
If a person with multiple personalities threatens suicide, is that person considered a hostage situation?

On Mon, 06 Feb 2017 01:52:50 -0000, James Wilkinson Sword wrote:

People still use analogue radio?

There are no digital radio signals here...

And a pilot light is better than lighting the bloody thing each time.

It's a pressure jet boiler not an oil fired Aga.

--
Cheers
Dave.

In message l.net,
Dave Liquorice writes
On Sun, 5 Feb 2017 19:57:23 +0000, Ian Jackson wrote:

1. While the ignition is sparking, there has been a considerable
increase in interference to the radio.

That shouln't happen, pretty sure ours produces no interference at
all.

As I said, the previous one (a Potterton, probably installed in the
early 70s) needed an additional suppressor. I simply asked the annual
service guy if anything could be done about the interference, and he
immediately produced a suppressor from his van. However, I would have
expected a more-modern boiler to have resistive ignition lead.

wanders off to bolier with MF radio tuned to inter station space
maybe a brief "tick".

I hear it on the FM band, where it's pretty vicious. But it's
essentially wideband.

2. The time the ignition runs for seems excessive long. The ignition
sequence is roughly
- The motor starts - and at the same time, the igniter starts sparking
(as heard on a nearby radio).

Odd. Are you sure the interference is the igniter and not the motor?

I think it's unlikely that the interference is from the motor, as it
(the interference) stops after about 40 seconds.

- After about 3 seconds, there is a slight click (presumably the oil
valve opening or pump starting).

AFAIK all burners have the pump driven by the fan motor. Click I'd
say if the valve opening but 3 seconds pre-run seems short.

Well, it might actually be 3 or 4 - but it's certainly not very long.
Apart from being long enough to ensure that the oil has got up to the
correct pressure, why would it need to be longer?

- After about 5 more seconds, there is a 'whump', and the boiler
ignites.

We get clickwhump after about 10 seconds of pre-run.

Ignition should be very quick, might be a weak spark (due to
knackered supression component(s))

I doubt if spark is weak, because boiler fires up readily, without any
obvious hesitation.

and/or bad adjustment and/or
erroded electrodes in relation to the nozzle.

I'm sure that the neither the igniter nor the ignition lead have ever
been changed during one of the annual services - or when the guy came 6
months ago to fix the lockout. He reckoned that the nozzle (the one
thing that HAS been changed annually), although the correct size, might
not be the right one (variations of the profile of the hole?) - and he
changed it. He also replaced the solenoid coil, which has a reputation
for going o/c when hot (a look at posts in online forums confirms this).
His other work was re-setting the oil pressure (which was too low).

- The boiler continues to burn as it should, but the ignition spark
(the interference) also continues for typically 30 to 40 seconds.

That seems wrong as well. The flame detection should turn the
ignition off once it detects a flame

Yes - I would have thought so. I wonder if the 40 seconds of sparks is a
default maximum?

and turn it back on if the flame
fails. Failure to ignite within a few tens of seconds will lead to a
lock-out.

Maybe the photocell is sooted up?

Or even faulty. There's certainly something keeping the spark going for
far longer than necessary.

The previous boiler flame detector was a spiral bi-metal probe
protruding into the flue, with a spindle that drove a microswitch.
Otherwise, the whole sequence of events was driven by a small electric
motor, with a long spindle turning a row of around 6 cams - each with a
microswitch. If there was a lockout, it took a full 7 minutes for the
sequence to get back to the start, while in the meantime, the motor and
fan ran on to purge the unburnt oil fumes.

I don't think there is any connection with the lock-out problem,

If several things become marginal, weak ignition long time to
ignite, poor flame detection longer time to detection, worn nozzle
bad spray pattern/big droplets hard to ignite, can all add up to a
lockout.

The Riello burner in our bolier has the following sequence:

Power on
Motor/pump runs for 12 seconds
Valve opens
Flame detected?
No
Igniter on
5 seconds elapsed?
No
Goto Flame Detected?
Yes
LOCKOUT, Valve closed, Igniter off, motor off, lockoout
indicator
on
Yes.
Igniter off, Valve open, Motor on
Goto Flame Detected?

As you can gather, I don't know what my boiler is supposed to do - but
it's probably similar,

I've rung the local service guy (who, last time, definitely seemed to
know what he was doing). He's going to call back to arrange a visit, and
as it's nearly time for its annual service, I'll get him to give the
boiler the full works.

Anyway, thanks for all the info. While I don't want to appear to be a
'know-all' customer, it's handy to know which sensible questions to ask,
and what background evidence might help him to diagnose the problems.
--
Ian

On Mon, 06 Feb 2017 09:45:02 -0000, Dave Liquorice wrote:

On Mon, 06 Feb 2017 01:52:50 -0000, James Wilkinson Sword wrote:

People still use analogue radio?

There are no digital radio signals here...

People still use radio?

And a pilot light is better than lighting the bloody thing each time.

It's a pressure jet boiler not an oil fired Aga.

I have a gas boiler with a pilot. It gives off no interference.

--
We used to have Empires run by Emperors.
Then Kingdoms run by Kings.
Now we have Countries.....

In message , James Wilkinson Sword
writes
On Mon, 06 Feb 2017 09:45:02 -0000, Dave Liquorice
wrote:

On Mon, 06 Feb 2017 01:52:50 -0000, James Wilkinson Sword wrote:

People still use analogue radio?

There are no digital radio signals here...

People still use radio?

And a pilot light is better than lighting the bloody thing each time.

It's a pressure jet boiler not an oil fired Aga.

I have a gas boiler with a pilot.

It's obviously much less practical to have a pilot light in an oil
boiler.

It gives off no interference.

Would you expect it to?

However, my 'previous previous' boiler (in my 'previous' house) used a
hot coil of wire to ignite the oil vapour (sort-of like a glow plug) -
and (of course) it too didn't give off interference. I would have been
surprised if it had.
--
Ian

On Mon, 06 Feb 2017 16:02:10 -0000, Ian Jackson wrote:

In message , James Wilkinson Sword
writes
On Mon, 06 Feb 2017 09:45:02 -0000, Dave Liquorice
wrote:

On Mon, 06 Feb 2017 01:52:50 -0000, James Wilkinson Sword wrote:

People still use analogue radio?

There are no digital radio signals here...

People still use radio?

And a pilot light is better than lighting the bloody thing each time.

It's a pressure jet boiler not an oil fired Aga.

I have a gas boiler with a pilot.

It's obviously much less practical to have a pilot light in an oil
boiler.

Why can there not be a tiny oil jet? Does the jet have to spray on to a hot sheet of metal?

It gives off no interference.

Would you expect it to?

No, I'm just saying it's better than having to ignite the gas every time.

However, my 'previous previous' boiler (in my 'previous' house) used a
hot coil of wire to ignite the oil vapour (sort-of like a glow plug) -
and (of course) it too didn't give off interference. I would have been
surprised if it had.

I've lived in two houses with oil boilers, neither interfered. I don't know how they functioned.

--
"I wonder who discovered we could get milk from cows and what the **** did he think he was doing?!" -- Billy Connolly

On Mon, 06 Feb 2017 16:05:25 -0000, James Wilkinson Sword wrote:

I have a gas boiler with a pilot.

Well I guess the waste heat stops the boiler freezing and the
£100/year it costs isn't worth worrying about.

Why can there not be a tiny oil jet?

The pump would have to run all the time.

Does the jet have to spray on to a hot sheet of metal?

Which jet? Your ficticious pilot jet or the main burner jet? The main
burner jet operates at the low 100's PSI and atomises the oil into a
very fine spray with a defined shape to match the cavity into which
it sprayed, ignited and burnt.

--
Cheers
Dave.

On Mon, 06 Feb 2017 21:13:51 -0000, Dave Liquorice wrote:

On Mon, 06 Feb 2017 16:05:25 -0000, James Wilkinson Sword wrote:

I have a gas boiler with a pilot.

Well I guess the waste heat stops the boiler freezing and the
£100/year it costs isn't worth worrying about.

My gas bill isn't that much in the months it's not used.

Why can there not be a tiny oil jet?

The pump would have to run all the time.

Oh.

Does the jet have to spray on to a hot sheet of metal?

Which jet? Your ficticious pilot jet or the main burner jet?

Either.

The main
burner jet operates at the low 100's PSI and atomises the oil into a
very fine spray with a defined shape to match the cavity into which
it sprayed, ignited and burnt.

I thought there was a hot plate. Maybe I'm thinking of a Primus Stove.

--
One tequila, two tequila, three tequila, floor.

On Mon, 6 Feb 2017 11:23:34 +0000, Ian Jackson wrote:

In message l.net,
However, I would have expected a more-modern boiler to have resistive
ignition lead.

Don't think ours has a lead, the igniter has a couple of insulated
sockets that the electrodes slide into with a locking screw to enable
adjustment.

I hear it on the FM band, where it's pretty vicious. But it's
essentially wideband.

Yee gads, that's bad...

I think it's unlikely that the interference is from the motor, as it
(the interference) stops after about 40 seconds.

Inclined to agree, just thinkimg of the age, mind you ours is of a
similar age or older with no hint of motor trouble. (SSSSHHHHHH...)

Click I'd say if the valve opening but 3 seconds pre-run seems
short.

Well, it might actually be 3 or 4 - but it's certainly not very long.
Apart from being long enough to ensure that the oil has got up to the
correct pressure, why would it need to be longer?

To purge the boiler/flue of any oil vapour if the valve is weeping a
bit. The right oil vapour/air mix will go BANG big time not just
whumpf...

I doubt if spark is weak, because boiler fires up readily, without any
obvious hesitation.

Apart from the time between click and whumpf when the igniter has
been running since the motor started.

The previous boiler flame detector was a spiral bi-metal probe
protruding into the flue, with a spindle that drove a microswitch.
Otherwise, the whole sequence of events was driven by a small electric
motor, with a long spindle turning a row of around 6 cams - each with a
microswitch. If there was a lockout, it took a full 7 minutes for the
sequence to get back to the start, while in the meantime, the motor and
fan ran on to purge the unburnt oil fumes.

The words Heath and Robinson spring to mind. B-)

As you can gather, I don't know what my boiler is supposed to do - but
it's probably similar,

Have a look at the burner fitted to your boiler and google any
maker/model information you can find. You'll probably be able to
download a manual for it that ought to contain the start sequence and
timings. There aren't many burner makers out there.

--
Cheers
Dave.

On Mon, 06 Feb 2017 21:21:20 -0000, James Wilkinson Sword wrote:

I thought there was a hot plate. Maybe I'm thinking of a Primus Stove.

A kerosene stove (or lantern) needs to be preheated and manually
pressurised before trying to light it. It'll then need to be
regularly pumped back up during use.

You may be thinking of an Aga type burner, they run 24/7. They can be
turned up and dowm by controlling how fast the oil drips into the
burner tray where it is distributed to wicks that vapourise and burn
the oil, like a candle or wicked (not mantled) oil lamp. The burn
should be an awful lot cleaner than either of those though!

--
Cheers
Dave.