Help understanding my Mano readings

zachary193 · Post by **zachary193** » Wed. Jan. 25, 2023 8:26 pm

Installed my Mano this eve . I just just hooked a screw and placed the line over the hole to get an idea .

The .05 was around 290 degrees stove top before tending Hose in the high

Second was after tending something didn’t seem right so I switched the hoses around.

Which way is correct . To me it seems it should be hooked up on the low side ?

ShawnLiNy · Post by **ShawnLiNy** » Wed. Jan. 25, 2023 8:32 pm

Zach technically the red negative side is the correct side but every one uses positive side ( a lot do)

zachary193 · Post by **zachary193** » Wed. Jan. 25, 2023 8:38 pm

ShawnLiNy wrote: ↑
Wed. Jan. 25, 2023 8:32 pm
Zach technically the red negative side is the correct side but every one uses positive side ( a lot do)

I was confused for a moment . I thought we should have Ben all dead my now !

waytomany?s · Post by **waytomany?s** » Wed. Jan. 25, 2023 8:47 pm

Everyone does it the opposite way cause it's easier to see.

warminmn · Post by **warminmn** » Wed. Jan. 25, 2023 9:24 pm

I use the Low side also.

Sunny Boy · Post by **Sunny Boy** » Wed. Jan. 25, 2023 9:29 pm

Not enough reading range showing when using the left side of the scale. I think all of us with a Mark II use the hose plugged into the "low" port.

Paul

zachary193 · Post by **zachary193** » Wed. Jan. 25, 2023 9:38 pm

I want to install a barometric this weekend . It’s Ben pretty windy and I feel like it pulls on the stove pretty hard at times .

Sunny Boy · Post by **Sunny Boy** » Wed. Jan. 25, 2023 9:47 pm

zachary193 wrote: ↑
Wed. Jan. 25, 2023 9:38 pm
I want to install a barometric this weekend . It’s Ben pretty windy and I feel like it pulls on the stove pretty hard at times .

The mano wild readings from wind looks worst that it is. Take the hose off the mano and gently blow across the end of the tube. That is how much the wind is affecting the chimney. A baro will help reduce the wild swings, but those wild swings are not sucking as much heat out as the mano may make you think.

Paul

zachary193 · Post by **zachary193** » Wed. Jan. 25, 2023 11:12 pm

Sunny Boy wrote: ↑
Wed. Jan. 25, 2023 9:47 pm
The mano wild readings from wind looks worst that it is. Take the hose off the mano and gently blow across the end of the tube. That is how much the wind is affecting the chimney. A baro will help reduce the wild swings, but those wild swings are not sucking as much heat out as the mano may make you think.

Paul

Ok , so say I increase primary air . I’m running my dial in the middle now . It maintains my house at the given outside temperatures now which are mild 35-40s . Say the outside temp dips and I increase the primary air to keep up with demand . That also increases draft as well .

So if the temp drops and the high winds pick up and my house calls for more heat . Wouldn’t turning the bi metallic up increase the amount of draft from ,05 to whatever the case may be .

I have not got to fiddle with settings to see if any changes affect this yet .

Draft is not a static ? It should increase with adjustments correct ?

Sunny Boy · Post by **Sunny Boy** » Wed. Jan. 25, 2023 11:43 pm

Yes, obviously, to get more heat you need to burn more fuel.

To burn more fuel, you need to increase the primary air intake.

That causes an increase in exhaust gas volume. The stove pipe diameter does not change so the exhaust gas speed increases for the pipe to be able to handle the exhaust volume increase.

And that increase in exhaust speed causes the mano to read higher to the right - if the tube is connected to the mano's "low" port.

A baro, or MPD helps control the burn by how they affect the draft strength (exhaust gas speed). The MPD by restricting exhaust flow, and the baro by cooling the exhaust with room air.

Paul

zachary193 · Post by **zachary193** » Wed. Jan. 25, 2023 11:51 pm

Sunny Boy wrote: ↑
Wed. Jan. 25, 2023 11:43 pm
Yes, obviously, to get more heat you need to burn more fuel.

To burn more fuel, you need to increase the primary air intake.

That causes an increase in exhaust gas volume. The stove pipe diameter does not change so the exhaust gas speed increases for the pipe to be able to handle the exhaust volume increase.

And that increase in exhaust speed causes the mano to read higher to the right - if the tube is connected to the mano's "low" port.

A baro, or MPD helps control the burn by how they affect the draft strength (exhaust gas speed). The MPD by restricting exhaust flow, and the baro by cooling the exhaust with room air.

Paul

Thanks , that was the best easiest to understand explanation I have ever heard .

Sunny Boy · Post by **Sunny Boy** » Wed. Jan. 25, 2023 11:57 pm

Also keep in mind. Coal stoves are a bit self-regulating to outside air temp changes. As the temp drops outside the stove and chimney system, the pressure difference increases (draft strengthens), which tends to force more primary air in and increase the heat output. Conversely, as it warms up outside the pressure difference drops and the stove reduces its heat output.

Not enough to handle big outside temp drops but it will deal with the minor changes so that you don't have to keep adjusting the dampers every hour.

Paul

nut · Post by **nut** » Thu. Jan. 26, 2023 7:32 am

The cave men never knew it was so complex.

Sunny Boy · Post by **Sunny Boy** » Thu. Jan. 26, 2023 7:55 am

nut wrote: ↑
Thu. Jan. 26, 2023 7:32 am
The cave men never knew it was so complex.

Hence the old saying, "Anyone can burn wood, but burning coal is an art form."

Paul

nut · Post by **nut** » Thu. Jan. 26, 2023 8:27 am

It sounds like these stokers have a learning curve. My hand fired stove is pretty easy if the coal does it's part. Shack it down, fill it up, rinse, repeat.

Help understanding my Mano readings

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