Worcester Danesmoor 15/19 oil fired with combustion readings

[billy_smith]

My son has just bought an old farm house with this boiler fitted.

The boiler looks very old although it works away fine, he phoned someone regarding a service/general health check, the engineer said he would need the service/installation manual for setting this up.

We've tried looking for a manual for this but nothing we have found is suitable for this boiler.

Anyone point us in the right direction.

I don't really have any additional info, there is a knob on the front panel along with 2 orange lights (mains on & lock out) nothing else.

There is no pump within the boiler and the house has a hot water tank.

Thanks

 

[Boilerman2]

Do not use this Engineer!! he is clearly a newbie or inexperienced!!

Under the top cover and on top of the exposed control panel you will see a label that indicates the correct Nozzle to use and the correct oil pressure - any decent Engineer will know that the CO2 should be 11.0 - 11.5% with "0" smoke and around 180'c on the flue gas temp!

(this info has just come out of my head no need for the manual for a Worcester Danesmoor!!)

 

[billy_smith]

Hi Boilerman2,

Thanks very much for that, you were spot on, we've just checked and there is a green plate (much like a vin plate)

It has the nozzle size required (0.55/80), it also states that the flue temp should be below 350 degree.

Upon checking other threads here it would seem we need to know oil pressure and air settings to set this up.

Should an experienced engineer have an idea what settings are required for certain nozzle sizes.

I checked the air reading on the boiler just now and it's reading 5 if that means anything.



Thanks in advance

 

[Boilerman2]

The Nozzle size and fuel pressure are specific to the boiler - flue temperature below 350'c is a legal requirement (boiler design) your boiler should come in at around 180'c -220'c - the air is not a specific setting, it must be set using a Combustion Analyser, to give as I have already said 11.0 -11.5% CO2

Any engineer that does not understand this SHOULD NOT BE WORKING ON YOUR BOILER!!

 

[billy_smith]

Thanks again for your input.

By chance we've got a shot of a Sprint V2 tester from a friend.

Now we stuck the probe into the flue terminal and the readings we got are below, the guy we borrowed the tester from knows nowt about oil he deals with gas only so he's not much help !

CO 9
C02 10.5
Ratio 0.0001
Pressure m/bar -0.02
02 6.8
XS air 48.0
Temp Flue 335
Efficiency 84.5

This is our last involvement, we were just curious too see what like the boiler is.

Going by that reading the flue temp is really high ?

Thanks again

 

[Burnerman]

Just sticking my nose in.....there's a flue gas sampling plug on the top of the boiler (cover off) that may give you more accurate readings.
There's also a baffle arrangement diagram nearby, and the baffles live beneath the access hatch, secured with 2 nuts. Worth cleaning them up!
John

 

[billy_smith]

Thanks John,

I've had a look, we can't see anything obvious regarding sample point for flue gas.

I do see the 2 nuts on top of the combustion chamber but we had no intention of going in !!

Would I be correct in saying there is a baffle diagram on the underside of this hatch ?

 

[Burnerman]

The baffle diagram is usually on the boiler top somewhere, but its only on a paper backing and maybe its gone.
No matter, if you remove those two nuts, the boiler top comes off to reveal the flue gas passage and the baffles within. The rope seal should be checked at the same time for fraying or disappearance.
The baffles just lift out, but do keep them in order - all they do is to slow down the passage of the hot gases so that more heat can get into the boiler water.
Its probably best to pull the burner out of the way first (one screw on the top of the flange usually) just to stop crud falling into the blast tube area.
The baffles shouldn't be too sooty, and you are likely to see yellow crusty sulphur deposits around the edges.....use a wire brush to clean them.
The flue sample plug is very close to this access hatch - maybe a square or hexagon nut is visible?
John

 

[billy_smith]

Excellent John thank you,

I've found the sample point on the top right hand side of the boiler, We've tried the tester again, the results are similar to the above although the flue temp is lower and the C02 is up to 11.

Doe's this mean much to you ?

 

[Burnerman]

I think the CO2 is spot on there!
Just for info, if the fuel oil pressure is correct and the nozzle is the recommended one, the CO2 level is adjusted by moving the air door screw.....but only a tiny bit at a time and you have to give the analyser time to sort itself out - results aren't immediate!
Nothing to worry about there - one of my favourite burners, the B9.
John

 

[xr4x4]

Sound fine to me, the flue temp is high, this could be down to the wrong nozzle, or the baffles have been messed with or cracked/bits missing.

As its working and seems to be heathly you could leave it be, or give it a service. Up to you.

 

[billy_smith]

Magic guys thanks for the input,

Well if all is well apart from the flue temp being high we might well leave it alone.

Would I be right in saying, the more air it gets the leaner it will run meaning the flue temp would be higher ?

Just relating this back to petrol engine tuning ?

 

[Burnerman]

Excess air will cause the oil flame to impinge on the back of the firebox i.e it will be blown away from the burner blast tube - and you don't want that.
The flue temp is a wee bit high but personally I've never had any real issues with this and its often due to the baffles being distorted due to overfiring.
John
Edit...I'm sure there are instructions to download from the Bosch Worcester website - under obsolete boilers.
J.

 

[Agile]

The flue gas temp was stated to be higher at the terminal then the test point on the boiler! Perhaps there is an afterburner ( as used on jet fighters? ) to increase it?

Would a high flue temp not indicate the HE needs cleaning?

Tony

 

[Burnerman]

Dead easy to do with the baffles out....broad bladed paint scraper at the ready!
John