Just Installed a Manometer.

Since it's too hot to keep it going, I decided to to take the opportunity to install a manometer. I odered it from Graingers on Thursday, and got on Friday. I used 1/8 pipe fittings at the stove end. I hope a 4" nipple will be enough to keep the automotive vacuum hose from melting/burning. It's rated for 250 degrees. The stove has a double wall design; so I'm hoping it will be okay. I know when I was burning wood that my chimney creates a terrific draft. I used to crack open the clean-out to relieve it some. Has anyone ever seen a clean-out door with a three window spin draft? I remember seeing one somewhere. Probably not a good idea with wood, but should be alright with coal.
Here are a few pics. Any comments are welcome. Good or especially bad. I rather have done right now and find out in January.
Charlie

That's plenty good. Mine is right on the pipe essentially. I had it up to 600* quite a few times, as my liquor-soaked brain tends to forget important things ... It just hardens the rubber. I just cut 1/4" off the end & all is well for this season.

Good to know, Thanks

So what do you adjust it to, negative .04?

From what I have read on here; it should be .04 to .08 in the black numbers. I assume that's positive. I have only zeroed it for now. With no fire going it's pulling .04

Wouldn't a positive pressure indicate a downdraft?

No, you are just using the positive scale to read the negative number easier as the scale is in the positive side of the meter. If you use the other port it will read negative numbers.

AAhhhhh I think I get it. If you use the "low" connection port you are reading negative inches of water column on the positive scale. If you use the "high" connection port you read positive inches of water column on the positive side of the scale. For measuring the draft you would use the "low" connection port. On a different type of application such as determining if a filter in a heating/ac duct is clogging up you would use both ports, the high piped to the upstream side of the filter and the low to the downstream side, measuring the differential in pressure. The gauge is designed for multiple applications. Do I have it right Ian?

That is correct. With a pitot tube, you can measure velocity I believe by using both ports. IIRC, the Dwyer comes with instructions about that application. Now I have to go down in the dungeon and look.

Recognize this?

http://www.dwyer-inst.com/PDF_files/markII-wsi_cat.pdf

Pitot.

http://www.dwyer-inst.com/Products/TOC.cfm?MainCa ... egoryID=36

Thanks Coke, You've explained it so that it's more understandable to me too! Luckily I got it right! Can you tell me the oil-fired boiler should have for a draft when running? I assume about the same.
Charlie

With a properly adjusted baro, you should never have to open the clean out door on your chimney.

the snowman.

Most oil burners want negative .04 inches of water column. (There are a few direct vent models that operate on a positive pressure with a SEALED burner and smoke pipe system.) If the draft is too much on a standard oil burner it can destort the flame in the fire box (in a bad way) and rush the flue gases out before they transfer all the heat the system could of extracted. Not enough draft can cause soot to puff out and gases to leak into the building. If a house is "tight" it can cause problems with natural draft chimneys. Air must be able to get into the house to make up for the gases going up the chimney, out an exhaust fan, or when a clothes dryer is running. That is why outside air kits for oil burners are getting more common in new construction. An overly tight house could cause CO to leak from the coal stove. It might be a worthwile experiment to turn on the clothes dryer while you have the coal stove running and see if it has any effect on the manometer readings. (If you do, please let us know!)

I'll check that out when I'm up and running again. I always have a basement window slid open slightly for that reason. Now that the stove has been down for about 24 hrs.,and the chimney is cool to touch, it's still pulling around -.04. You can see an instant response when you reach over and tap the baro open. It will be interesting to see how much draft there is when we are deep into heating season.
Charlie

Now that the baro is installed what do you use the readings for?

Nice work body hammer. Look good and should last many years.

Maxie, a manometer measures the vacuum ( negative pressure below 0 psig -atmospheric pressure) in your flue. Other words, it read , the sucking power pulling the exhaust up the flue into the atmosphere. If your vacuum is too strong, it will pull excessive air through the stove damper thus adding more air across your firebox than required for a consistent burn. Too much air and you waste coal with excessive produced heat.

What exactly is a body hammer?