Going to buy a Dwyer Magnehelic Series 2000 gauge...what range?

[bill-e]

Hi folks,

I have an XXV and I'm going to pick up a gauge. What range is best, 0-1 or 0-2? I would think 0-1 would be more accurate for what we need but wanted to double check first.

Thanks
Bill

 

[maple1]

I'm not sure the 2000 will give the preciseness you will be looking for at low draft conditions. It might, but with draft in the 0.05" range, the needle will be working in the bottom 10% or so of it's range.

I've got one of these (used for a boiler and not a pellet stove - so not sure what your specd draft or pressure diff is), the Model 25:

http://www.dwyer-inst.com/Product/Pressure/Manometers/Stationary/SeriesMarkII

Might not be as pretty, but it's more accurate on the bottom end.

 

[Doug Doty]

0 to 1, all of my reading are in the 0 to .4 range in my stove.

(broken image removed)

 

[maple1]

I think you mean 0.04.

 

[bill-e]

Maple1, actually the Harman manual says .4 for low draft and .6 for high.....not .0X

 

[Doug Doty]

I think Bill was looking at my picture with .04 showing in the meter, the stove was off !! I changed it to an operating picture to elim. confusion . It shows as much as .04 type #'s when off based on natural drafts I suppose. I have thus far seen a high of .53 on just now's start up with the intake draft restricted with the butterfly. My zero is off .02 or so even outside, it was trivial so I did not even zero it out, I should, but wanted to learn a bit about it before I started turning screws.

Sitting outside the mall waiting on the wife, nice to have the hearth forum to peruse while killing time.

 

[hyfire]

0-.5" w.c. would work best for any pellet stove...

 

[Doug Doty]

Sounds logical but mine just pulled .48 on a startup until the fire lit off and it started dropping down ?? and spiked to .53 playing with the intake air draft adjustment.

 

[Doug Doty]

I found this in a P68 harman manual.
(broken image removed)

 

[maple1]

I think Bill was looking at my picture with .04 showing in the meter, the stove was off !! I changed it to an operating picture to elim. confusion . It shows as much as .04 type #'s when off based on natural drafts I suppose. I have thus far seen a high of .53 on just now's start up with the intake draft restricted with the butterfly. My zero is off .02 or so even outside, it was trivial so I did not even zero it out, I should, but wanted to learn a bit about it before I started turning screws.

Sitting outside the mall waiting on the wife, nice to have the hearth forum to peruse while killing time.

Ha - someone pulled the old switcheroo with the pic I was looking at here a while ago.

 

[Doug Doty]

I could'a not admitted it and left ya hang !!

 

[bill-e]

Just to close this out I purchased the 0-1 single scale for about 59$ delivered from Amazon and set my low end to .40 (could go as low as .30) and my high end at about .52

 

[Doug Doty]

Nice tool !!

 

[Randy Fischer]

Just to close this out I purchased the 0-1 single scale for about 59$ delivered from Amazon and set my low end to .40 (could go as low as .30) and my high end at about .52

Newbie here, anyone willing to write a paragraph on why you need a meter like this and how does it get installed?

 

[Doug Doty]

Most stoves are designed to burn best at a certain range of vacuum in the firebox to pull air up through the holes in the bottom of the fire pot. This just allows you to verify where you are at with accuracy. It is also a diagnostic tool for cases where your stove might be shutting off due to a leak and the vacuum switch cutting power to the auger or maybe for just sniffing out some leaky door or other seals.

 

[Randy Fischer]

So do you have to put a probe connected to the meter in the firebox? Assume it's the pressure difference compared to the room?

 

[Doug Doty]

These pellet stoves have vacuum pressure switches to shut down the auger if the door is open of any length of time or an air leak reduces the vacuum below the switch setting. there is usually a silicone hose from a port on the back side of the fire box to the switch and in my case I just " T'd " into that line.

 

[hyfire]

If your stove or flue is clogged you will know before the pressure switch trips, with this gauge, basically.

 

[chken]

Newbie here, anyone willing to write a paragraph on why you need a meter like this and how does it get installed?

Sometimes it's part of the mfr.'s installation process to tune the stove using a manometer or magnehelic. Takes some of the guesswork out of the process, given the uniqueness of each installation. It's also useful as a diagnostic tool for when a stove doesn't seem to burn properly. Whether you can use one on your stove depends upon whether the mfr of your stove set it up for one. I don't know enough about other stoves to know whether they all do or don't. All I know is that my stove's installation guide has it.

 

[Randy Fischer]

Thanks folks for the info, anyone know how hard it is with a Harman 52i?

 

[Luv2burnPellets]

I found this in a P68 harman manual.
(broken image removed)

So is there an adjustment screw for the high draft set point as well as the low draft point? Is the Dwyer model 2100 ( 0-1" ) the correct model to use? I see that the model 2100 has the ability to gage differential pressure also and has two ports , a high and low. How would that gage be used, assuming it is the correct gage to use? I would like to check my P68 as I am not certain the installer used one and would like to check my fathers stoves, as he has a P68 and a P43.

 

[chken]

Thanks folks for the info, anyone know how hard it is with a Harman 52i?

So is there an adjustment screw for the high draft set point as well as the low draft point? Is the Dwyer model 2100 ( 0-1" ) the correct model to use? I see that the model 2100 has the ability to gage differential pressure also and has two ports , a high and low. How would that gage be used, assuming it is the correct gage to use? I would like to check my P68 as I am not certain the installer used one and would like to check my fathers stoves, as he has a P68 and a P43.

I'm thinking you and Randy should post a new thread asking for "draft settings for Harman P-series" and you'll either get lots of answers or you'll get sent to a thread that already discusses the topic ad nauseum since Harmans are the most popularly discussed stoves on Hearth.

 

[Doug Doty]

You can see a picture of my Dwyer gauge up higher in this link, it is suitable for all pellet stoves including Harmans. They do have an adjustment that some of the cheaper stoves do not. I use a differential type of gauge to measure in and out natural and lp gas pressures when working on furnaces. Also for measuring pressure drop across evaporators and filters.