I have some questions about my thirty year old hot water, oil fired furnace made by The Peerless Heater Company of Boyertown, PA, Model  JO3L WPCT.

The furnace is cast iron and the heated water is in a chamber that extends to the bottom of the furnace (wet base?).  The fire chamber had a lining (asbestos?) which has deteriorated.

Does running the furnace without the lining harm the furnace?

Does that reduce the efficiency of the furnace?

The furnace gun is labeled “Peerless FH F12.”  It has has a fuel pump made by Webster Electric.  I did not see a model number.

Does that pump have a fuel filter inside?  I took the end piece off but did not see any.

I was told that the air shuttle (air adjustment) should be adjusted so that the tips of the flame are just no longer smokey then adjusted for a little more air.   I was told to do that to ensure that the flame is not running dirty and that although that might reduce the efficiency that is better than having a dirty flame.  I do not have an efficiency test set.

Is that the best way for me to adjust the air?

What is the best efficiency that one can get form such a furnace?

Thank you for any information that you provide.