Potterton statesman 45/50 nozzel size?

[Inverness]

cant find the spec I need to service this boiler and I'm not planning in making two visits so getting info and parts ready but can't find any info on the nozzel size.Any advice would be appreciate.

 

[DjClubber]

cant find the spec I need to service this boiler and I'm not planning in making two visits so getting info and parts ready but can't find any info on the nozzel size.Any advice would be appreciate.

This may Help... Ive got more or less all Oil Boiler Manuals Handy. . .

 

[Inverness]

Can't seem to download it mate

 

[SJB060685]

If you have OFTEC books or even their pocket guide it will show you how to calculate a suitable nozzle size and pressure depending on burner output needs. I did look online quickly but couldnt see the nozzle sizes etc in a manual.

 

[Tea-Break]

You can easily find the manuals on line.
Unfortunately, they do not seem to contain combustion settings. So you’ll have to work it out.
My calculations make it .45 US Gals @ 100PSI = 50000BTUs (15kW).

 

[SJB060685]

My calculations suggest you need a 0.45gph nozzle at 8 bar pressure

 

[SJB060685]

Bare in mind a slightly bigger nozzle will require less pressure and a slightly smaller one will require more. Neither Tea-Break or I are wrong, we’ve just worked it out slightly differently, however too low a pressure and the fuel won’t atomise properly

 

[SimonG]

How many nozzles do you carry. I have about 80 to 100 on the van.

 

[SJB060685]

Anyone working with oil should have a variety of sizes, angles and patterns

 

[MikeJhn]

The RDB1 manual says 10bar Page 8 Table A for Kerosene.

https://www.rielloburners.co.uk/images/content/downloads/RDB1-2_2902489-18.pdf

And this should give you the nozzle needed: http://www.delavaninc.com/pdf/total_look.pdf

 

[Sharp Point]

How many nozzles do you carry. I have about 80 to 100 on the van.

Well that’s just god damn greedy...

 

[Tea-Break]

The RDB1 manual says 10bar Page 8 Table A for Kerosene.

https://www.rielloburners.co.uk/images/content/downloads/RDB1-2_2902489-18.pdf

And this should give you the nozzle needed: http://www.delavaninc.com/pdf/total_look.pdf

I think this relates to the generic pump pressure range.
The boiler in question is quite small 45/50.
Therefore the correct nozzle should be .45-.50.
As SJB correctly states, going below 100PSI is not recommended.
To return to the the original post. Without wishing to be condescending, this is all bread ‘n butter stuff for any oil engineer.

 

[MikeJhn]

It's categoric at a maximum of 10bar, how many times do we see posts that say follow the manufacturers instructions, concerning pump pressure and nozzle size.

The Delavan catalogue on page 7 also says to find the correct nozzle:

GPH = BTU Input / 140,000 or GPH = BTU Output/(Efficiency %) x 140,000

 

[Best]

Ten bar is really too high and is a max limit for oil pumps on kerosine I believe. Higher can damage the pump
7 to 9 bar is range.
Diesel can be higher.

On outputs you will find the nozzle size will closely match x 1000 the btus with kerosine.
(.75 nozzle at 7 or 8 bar kerosine usually going to give 75,000 btus or more)

 

[MikeJhn]

To obtain 0.75 from 75,000 you would need to divide by 100,000.

 

[SJB060685]

If you read burner manuals especially Riello it clearly states that it’s 10 bar max for kerosene, for the very reasons Best has mentioned above, class D is usually higher pressure and different nozzles/patterns. I didn’t feel the need to mention this before as anyone working with these burners should know this and study all sorts of manuals. As best said usual range is between 7-9 bar, but like I said too low and you’ll get atomisation and combustion problems.
If you haven’t got one already Inverness phone OFTEC and buy their pocket guide, if I remember correctly it’s about £5 plus delivery. It has these calculations in there plus all the other important information for checking tanks etc etc.

 

[MikeJhn]

That's what I said 10bar maximum, the OP posted they did not have the manual for the unit, so I posted what I thought was a helpful link to the burner and nozzle calculations, the criticism's where unnecessary, be helpful by all means, but don't denigrate others for trying to help.

 

[SJB060685]

I’m just clarifying this to anyone watching this thread, it’s not aimed at anyone in particular

 

[Best]

To obtain 0.75 from 75,000 you would need to divide by 100,000.

Lol! True! I did post that at 2.40 am.
Although tbh I just always have in my head to add 3 zeros to the smaller nozzles size (without thinking of the position of the point)
But as you say, multiply by 100,000.

Just was something I always noticed with boilers on kerosine and still applies as a rough guide despite the increase in efficiency in HE boilers.

 

[SJB060685]

Best you say multiply smaller nozzle size by 100000 to get btu’s. At what pressure is this assuming? And I assume this figure is burner input, not boiler output or efficiency must be taken into consideration?

 

[Best]

Best you say multiply smaller nozzle size by 100000 to get btu’s. At what pressure is this assuming? And I assume this figure is burner input, not boiler output or efficiency must be taken into consideration?

Only saying that as a very rough estimate of boiler output for kerosine and at 7 bar or 8 max oil pressure.
At 9 bar the output will be higher.
Just really judging that on all boiler specs, of various types.
Nothing to rely on, but just an indication that a nozzle on a boiler you go to is wrong size.

 

[SJB060685]

Yeah I just done some examples on my EOGB calculator and what you say is a vary rough figure, depending on pressure and efficiency. I’ll stick to what I know lol

 

[MikeJhn]

Best you say multiply smaller nozzle size by 100000 to get btu’s. At what pressure is this assuming

All nozzle output is quoted at 100psi.

 

[Tea-Break]

All nozzle output is quoted at 100psi.

Sorry, I don’t understand ?

 

[MikeJhn]

Any nozzle size is quoted on its GPH output at 100psi.