Wood Boiler Questions

[PA_MIKE]

My place had a Royall indoor wood boiler installed in it when I purchased the home.
I am going to use it this winter. What should I set the aquastat temps to? I place on burning wood and coal. The draft blower turns on with the aquastat. But the flu is manual. How should I set the flu?

[MELOC]

ross can help you, i am sure.

i would guess it depends on the delivery system. you want higher temps for radiators and lower temps for floor heating. i have cast iron radiators and i run my system in the 170 degree range. i have a weird setup in a sense, but i am rusty on the details of why, so i won't go into detail, lol. i would suspect you would want 170 as a low and 190 as a high temp.

[Ross]

Sure put me on the spot, I'm certified on oil burners but run (have run) lot's of wood burners. I would say the manual damper is for a no power running situation so you can regulate the draft. I would set it open when running on power. We've used the manual dampers to stop a down draft to get a fire started. I certainly wouldn't run the power damper leaving the manual damper closed!

I'd try for a manual to set the aquastat, but what Meloc suggests sounds safe enough. What sort of distribution system is the boiler connected to? Rads, in floor radient, air handler and ducts, or?

[MELOC]

yeah, you don't want to have 170-190 with floor radient heat i would imagine. i meant to say that, but i had just erased a paragraph of useless rambling about my system and i forgot, lol.

[PA_MIKE]

Let me clarify.... There is a manual flue and a blower draft. The type of heat is like a baseboard heat. What kind of pressure? How do I regulate the pressure?

Right now I have been running 140 low and 160 high ... the pressure says 34lbs when at 160.

Thanks in advance.

[Ross]

Those temps would be low for an oil fired boiler; however, the manufactuer may have it set lower for a greater margin of safety. Wood burning is less controlable. I'll asume there's make up water valve and bypass water feed, and that's where you adjust the pressure. The manual damper is in the vent pipe before the chimney?

[Ross]

One more thing (I forgot) the reason I asked about the distribution system is no power operation. It's possible for some systems to gavity feed the hot water (steam more likely) through a well designed radiator system. If your pressure guage sits on a pigtail pipe it's very likely steam capable, if on a straight pipe it's not. (Or it's not set up for steam at least) Nothing to fool with if you're running steam, I'd get a fitter in to show you first hand.......... Not that 160 degrees is even close to steam (212 degrees) but it makes gravity (no power) operation through baseboards a little less workable and therefore the damper (in the vent pipe) really just for startups. If it's on the boiler it's self, you probably just match a setting to the type of wood you're burning and the draft conditions. It's going to be very hands on, not set and forget.

[PA_MIKE]

It is a flu dampner. What should I keep the pressure at? Thanks for your help

[Ross]

Whoo boy I'm gonna pass on that Q cause A: it's important to get right, and B: it's out of my feild of expertise. You need an owners manual, try a Google search for your boiler or the phone book for local dealers.

[haypoint]

I don't think you want any pressure beyond the weight of the water above the furnace. I ran a wood fired boiler with cast iron radiators for 30 years. It was designed in the 1930 and didn't require a pump, the hot water would simply rise and the cooler water settled to the boiler. I operated both the air intake and damper manually. I operated it with a 110 degree water temperature at the furnace. I'd guess the radiators would have been warmer. Is there an expansion tank to insure that the system can not build pressure?
My boiler had a non-electric temperature control that was broken. When it did work, a brass "wafer" would expand under heat and tip the air intake closed and shut the damper. It was a sort of "teeter-totter" affair and you could adjust it to various settings.

[rambler]

My experience is almost a 100% copy of haypoint. House was build in Minnesota in 1926, & had only the gravity wood boiler for heat until 1972. (My ancestors did not take vaccation, it never froze, no antifreeze, never drained.)

You need enough pressure to allow flow throught the stories of the house, but less is better.

I think 30+ would be very high, but I am not qualified to say. I think just over 20 is what mine was at - same as the oil burner - they are interconnected.

You might want to go to Yahoo, & check out the 'Woodheat' newsgroup area. There are some real good wood boiler people there. They are helpfull. They really like your type of setup over the new outdoor boilers, so you will have an 'in'.

--->Paul

[MELOC]

i think my hot water system runs at 18 psi.