Just moved in , Need info on wood and oil boilers

[jcsheppard]

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.

 

[Eric Johnson]

I like the original aquastat settings better, especially since you're not getting enough domestic hot water.

Are you around enough to turn the oil burner off and keep the wood going for a couple of days? I'd try that and adjust the wood settings to where you want them. Then worry about the oil later. Depends on what your priorities are, I guess.

I wouldn't worry about the pressure, either. Most boilers operate in the 12 to 15 psi range, but anything less than 30 is usually OK, IME.

 

[jcsheppard]

Wow! thanks for getting back to me so fast, i think i'm gonna love this place. i love the whole idea of having boilers. i'm getting a wood cutting permit this spring, so i got something else to learn too.

I am not normally home long enough to turn off the oil burner. I would like to try it though. How do i turn off the oil burner?
What does the diff do?
How come the wood boiler has two aquastats? One aquastat is like the one on the oil boiler but has no diff and the other has just one temperature setting (mine is at 160) and a diff(5) Is the wood circulator always on? It just seems that i should be getting more heat to the rads (i have the big old cast iron rads). As i have said , my house wont get any warmer than 70 with the wood boiler.

 

[Eric Johnson]

The differential on a Honeywell aquastat sets the range that the stat will drop or rise to before kicking back on. If your high limit is set at 180 with a 20-degree differential, in other words, the pump (or whatever) will kick on at 180, but it will drop down to 160 before shutting back off. It provides a reasonable amount of swing so that your equipment isn't switching on and off if the temp hovers around the setpoint.

If you have two aquastats on your wood boiler, one probably runs the pump and one runs the draft blower. Or, perhaps one is the dump zone trigger (i.e., turns on the pump at 200 no matter what, to dissipate the heat from the boiler). Something like that.

Oil burners tend to have three-function stats. I'll let somebody else explain that, because I really don't.

There is probably a power switch with a red plate that allows you to turn off your oil burner from the first floor of your house. If there isn't, there should be. Or, you could switch off the breaker at the electrical panel. Unfortunately, this might also shut off your pump(s), which you don't want to do if the wood side is running. Again, maybe somebody more familiar with oil burners than I am can help us out with this one.

 

[ssupercoolss]

become friends with your local heating/plumbing contractor. i really dont think that once you are dealing with a wood boiler added to an oil boiler, the oil man will say " these settings will work best for you and make sure that you burn as little oil as possible." i plan to sever all ties with my oil company when my add-on wood boiler gets installed.

 

[Mainewood]

Wow! thanks for getting back to me so fast, i think i'm gonna love this place. i love the whole idea of having boilers. i'm getting a wood cutting permit this spring, so i got something else to learn too.

I am not normally home long enough to turn off the oil burner. I would like to try it though. How do i turn off the oil burner? What does the diff do?
How come the wood boiler has two aquastats? One aquastat is like the one on the oil boiler but has no diff and the other has just one temperature setting (mine is at 160) and a diff(5) Is the wood circulator always on? It just seems that i should be getting more heat to the rads (i have the big old cast iron rads). As i have said , my house wont get any warmer than 70 with the wood boiler.

jcsheppard, You do not need to turn off your oil boiler. Try setting the oil triple aquastat settings at 140-lo & 155 hi, this will keep the oil burner from firing as often. Turn the aquastat settings on the wood boiler to 180 lo & 200 hi. You may use more wood at this setting but the fire will burn hotter, providing more heat to the radiators. Turning down the oil settings will give you a wider range in operating the wood boiler before the oil kicks in. If you need domestic hot water and the temp. is down in the wood boiler, you will need to turn up the oil settings. The single aquastat on the wood boiler that controls the mixing circulator may be set at as low as 140 so that it continues mixing water from the wood boiler to the oil boiler.