Too much vacuum on RDB burner.

[HampshireSteve]

can you help. my boiler was failing to light and yesterday my engineer (very respected) did 2 things. 1) removed debris from filer where oil leaves tank, and 2) adjusted air intake to reduce amount of air which was blowing out flame. Spent a fair bt of time measuring gases and adjusting both oil pressure and air to get right co2.
all excellent and now very quiet in lighting. BUT this morning wouldnt light at all and when i held hand over air intake flexi tube it was sucking like a vacuum cleaner ( set at just below 4).

any ideas why it should be sucking so hard. I resolved it in short term by resting flexi tube opening against body of the flexi tube so reduces air and boiler lit but obviously i am now not using regulated air intake just luck of the draw. Will i need a new burner or can the air air intake part be replaced on the existing burner? will also call my excellent engineer but it is new years day and cold so not likely to get a visit!

 

[oilman]

Your measurement method is hardly valid. Call your excellent and well respected engineer. Running with a partial blockage is not a controlled approach.

 

[wilhelm]

if its a balanced flue. sounds like spent gasses putting flame out.

 

[Agile]

This is a question to the oil experts.

The boiler was carefully set up to run when hot at the optimum settings.

Many oil boilers are housed outside the thermal envelope of the house and over night will go down to freezing temperatures.

Could it just be the difference between the cold setting and the hot setting ( as it was adjusted for ) ?

Cars have to get over this problem by using a choke !

Tony

 

[oilman]

This is not a car and works more like a diesel which do not have chokes. I attend dozens of outside boilers, and cold starts are not a factor.


Does your blowlamp suffer starting difficulties in the cold?

 

[gremlin16]

I attend dozens of outside boilers, and cold starts are not a factor.

Not if you have a can of Easy Start handy.

 

[Agile]

This is not a car and works more like a diesel which do not have chokes. I attend dozens of outside boilers, and cold starts are not a factor.

My diesel ( car ) has glow plugs to preheat the CC and help the mixture to ignite! As a couple of them have failed it has to have multiple attempts to start in this weather.

Well, if the cold weather is not a reason why his boiler needs a richer mixture to start, then what is the problem?

Tony

 

[WDIK]

if it were a gasoil / 37sec / diesel burner, then waxing can be a problem.

the problem being, lower atomisation, not a prevelant problem with 27sec kerosine / parafine.

lower nozzle sizes and increased pump pressures overcome gasoil burner problems, but are not indicated as a cure for kerosine burners, normally.

gas oil burners also use trace heating and preheaters, again rarely with kerosine burners.

generally, badly setup and badly serviced burners are the cause of bad lighting.

most problems can be resolved with a tiger loop.

 

[Slugbabydotcom]

Spank my botty if I am wrong but isnt it 32 sec gas oil and 28 sec kerosene?