Hi, i am very new to this so bear with me. I just moved into a big two storey house approx 900 square feet per floor (the basement is unheated but is always warm, i assume cause of the two boilers). It has two boilers; an oil fired boiler connected with a wood fired boiler. When I moved in I signed a maintenance contract with an oil delivery company (Ultramar) whereby they do all the maintenance on my oil fired boiler. Well after a couple months of 800 dollar (per month) oil bills, I bought 2 cords of wood (aready seasoned) so I wouldn't lose my shirt this winter. The old home owner assuerd me that the wood boiler worked , so after a few hours of messing around with the valves i figured it out (i think). Long story short, when I got a good fire burning in the wood boiler everything was going fine until the fire died out when i went to sleep. I awoke to extreme heat and to the sound of my oil boiler firing. My oil boiler wouldn't shut off no matter what i did. Anyway on to the repair guy. I got charged a lot ot fix it (400 dollars) he said it was the dump zone valve causing it. Now i'm still learning but i need help. The old home owner left these guidlines for me (he's left the country so i can't get it touch with him anymore) OWNER SETTINGGS Wood fired boiler(WF 100 New Yorker) L4006B Hi 190, diff 10 ; L4062A Hi 220, low 200 Oil fired boiler(saturn kerr, riello burner) Triple aquastat-relay L8124G high 200 low 180 diff 15 When the service tech fixed the boiler he changed the settings like this Wood- hi 160 diff 5 hi200 low 170 Oil-(triple aquastat) hi 180 lo 160 diff 15 The service guy said that these are the proper settings and that i shouldn't change them, i don't buy that so i'm trying to learn what i can. It dosen't seem to run as efficient now. I can't have a shower without the oil kicking in , i can only run hot water for about a minute or so then the oil comes on. the temp guage on the wood boiler is almost always above 180 when i have a fire in but the house won't get warmer that 70, i always keep the thermostat on 77 but only when the oil boiler is on alone will it get that warm. Also it says that there is 18 psi on both guages (oil and wood boilers) but the wood boiler says that it has a working pressure of 10 to 14 psi. Is this a problem? should i be concerned? both relief valves are set at 30 psi. Any help would be greatly appreciated, i'm always trying to learn more. On a side note its almost impossible to get anyone to work on boilers here, apparently there is a huge shotage of people who know about them.