Dwyer manometer

[Rockstar1346]

Hi guys I tried ordering a manometer but they cancelled my order so long story short had to find an hvac company that sells them. Anyways I’m wondering what prob I need to connect to my flue as customer service was 0 help saying it doesn’t use a probe.. any help would be appreciated!

 

[sloeffle]

I used a foot of 3/8" OD bendable copper tubing. The small tube from the Dwyer Mark 25 will fit inside the copper tubing.

 

[Woodcutter Tom]

I use copper tubing the same size as the rubber tubing that comes with the manometer. (Probably 1/4" OD. ; Same size as from water supply to ice maker in refrigerator or from water line to humidifier.) I used heat shrink wrap to connect copper to rubber tubing.
I drilled a 1/4" hole in backside of stove pipe. Insert copper tube about 1 1/2" into hole. All works good.

 

[EbS-P]

I got a magnahelic like this one 30$ shipped.

(broken link removed to https://www.ebay.com/itm/265777436665?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=_MdUvIF5Tsa&sssrc=2349624&ssuid=sKo6Y63yQve&var=&widget_ver=artemis&media=COPY)

 

[Woodcutter Tom]

I got a magnahelic like this one 30$ shipped.

(broken link removed to https://www.ebay.com/itm/265777436665?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=_MdUvIF5Tsa&sssrc=2349624&ssuid=sKo6Y63yQve&var=&widget_ver=artemis&media=COPY)

I do not think that will work very well for you. The range is too large. I have a Dwyer 2000-00 with a range of 0 - .25. This one is would be much better for low draft readings.
(got it a few years back for $20.00 shipped)

Saw this on ebay: (broken link removed to https://www.ebay.com/itm/265779999068?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D29db29a6ee5b40858277dc3448b08bf8%26pid%3D101224%26rk%3D5%26rkt%3D5%26sd%3D265777436665%26itm%3D265779999068%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWeb&_trksid=p2047675.c101224.m-1)

 

[EbS-P]

I do not think that will work very well for you. The range is too large. I have a Dwyer 2000-00 with a range of 0 - .25. This one is would be much better for low draft readings.
(got it a few years back for $20.00 shipped)

Saw this on ebay: (broken link removed to https://www.ebay.com/itm/265779999068?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D29db29a6ee5b40858277dc3448b08bf8%26pid%3D101224%26rk%3D5%26rkt%3D5%26sd%3D265777436665%26itm%3D265779999068%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWeb&_trksid=p2047675.c101224.m-1)

View attachment 300538

Agreed get the one with the 0-.25 “wc

 

[Rockstar1346]

Sorry for the late reply death in the family but Thanks for the help everyone I got all the supplies needed to hook this thing up hopefully this weekend. How close to the furnace should the BD be or should it be closer to the chimney? I’ll post some pictures when I can but I’ve watched some videos and some say close to the stack others close to the unit itself so kind of confusing info. Anyways thanks for your help guys much appreciated

 

[mikey]

What is a manometer?

 

[EbS-P]

What is a manometer?

Device that measures pressure. Almost always a differential pressure.

 

[brenndatomu]

Sorry for the late reply death in the family but Thanks for the help everyone I got all the supplies needed to hook this thing up hopefully this weekend. How close to the furnace should the BD be or should it be closer to the chimney? I’ll post some pictures when I can but I’ve watched some videos and some say close to the stack others close to the unit itself so kind of confusing info. Anyways thanks for your help guys much appreciated

The Dwyer needs to be tied in between the furnace and any type of damper...which the damper (baro, right?) should come with a diagram that shows where and where not to put it...here https://www.fieldcontrols.com/wp-content/uploads/2019/05/01575700_TypeRC_Rev_B_04-15.pdf

 

[JRHAWK9]

This is the Magnehelic I have. I also have a Dwyer tee'd into the same line for redundancy. The Dwyer seems quicker to react than the Magnehelic.

 

[Rockstar1346]

The Dwyer needs to be tied in between the furnace and any type of damper...which the damper (baro, right?) should come with a diagram that shows where and where not to put it...here https://www.fieldcontrols.com/wp-content/uploads/2019/05/01575700_TypeRC_Rev_B_04-15.pdf

That was super helpful thank you! It didn’t have anything in the box at all just the BD. That being said I think I got it all setup just have to get some bendable copper tubing this week. So I guess final question does this setup look correct or did I do something wrong? Thanks guys

 

[maple1]

Looks ok to me.

 

[brenndatomu]

Yup, that should work

 

[Kenny4454]

I ordered my Magnehelic gauge as mentioned above and plan on using 1/4 copper tubing from HD. I understand that it needs to be located between the barometric damper and the furnace, but have been seeing mixed reviews on if its better to be closer to the damper or the flue collar. Wanted to get an opinion based on my setup before I drill the hole. Also, does it make any difference if the hole should be on side or top of flue pipe?

My other question is what fitting/tip would be best to secure the line to the pipe. I was going to just get a standard compression fitting, but thought it may not be snug enough in the pipe. Also starting looking at the static pressure tip A301 and A307 from dwyer.

Interested to hear what you all found best in location (and accuracy in readings) and fitting to allow for the connection not to fall out but can be easily removed to clean.

 

[brenndatomu]

I ordered my Magnehelic gauge as mentioned above and plan on using 1/4 copper tubing from HD. I understand that it needs to be located between the barometric damper and the furnace, but have been seeing mixed reviews on if its better to be closer to the damper or the flue collar. Wanted to get an opinion based on my setup before I drill the hole. Also, does it make any difference if the hole should be on side or top of flue pipe?

You don't want it close to anything...in the middle of a straight section is best...and I have tried different positions on the pipe, didn't see a difference...probably because the velocity is fairly low.

My other question is what fitting/tip would be best to secure the line to the pipe. I was going to just get a standard compression fitting, but thought it may not be snug enough in the pipe. Also starting looking at the static pressure tip A301 and A307 from dwyer.

A NPT to compression fitting will work fine.
As I may have already mentioned, I just bend the copper into an S shape and hang it in the hole, works fine.
What do you plan on using the pressure tip for?

 

[Kenny4454]

You don't want it close to anything...in the middle of a straight section is best...and I have tried different positions on the pipe, didn't see a difference...probably because the velocity is fairly low.

A NPT to compression fitting will work fine.
As I may have already mentioned, I just bend the copper into an S shape and hang it in the hole, works fine.
What do you plan on using the pressure tip for?

Thank you for the quick reply! I have read several of your posts since joining the forum and I appreciate any advice I can get for a newbie like myself. I did a lot of research and called the company several times before ordering. In addition, I spoke to Micdrew (a fellow Marylander) to get his insight on his experience before ordering. I have only had my setup up and running for 2 weeks and after going off what the manual and the videos say regarding the barometric damper setting and hearing about experiences on this site, I felt that getting a manometer would really help me get things dialed in with a flue that is ~25 to 30 ft tall.

I like that S hook idea! If I go this route does is matter which orientation that 1/4 copper pipe is facing inside the pipe or how far it is in the pipe?

What do you plan on using the pressure tip for?

I just saw that as an option on Dwyers site and noticed that it has several small holes rather then just the ID of the 1/4 pipe so didn't know if it was necessary for accuracy.

A few other questions I have so far for yourself or any other experienced users:

1. After 2 weeks of operation is the build up of what appears to either be creosote flakes (or possibly rust ?) normally around the edges of the backwall surrounding the backplate (see picture)?
2. It is normal for the thermocouple wire jacket to turn golden brown and even black in places (see picture)?
3. My HVAC installer created gravity backdraft flaps as directed by Lampa using the drawing they provided . However, since there are gaps around edge and top seem to decrease the air pressure in my house vents when my LP furnace is in use (since some air is bleeding back through the VF100 furnace). Seems like the intention is to allow for air to gravity feed in power failure, but it also seems to create a loss in air pressure when the other system is in use. Have you encountered this issue before?
4. What should the inside and outside flue temp readings be and at which location on the pipe? I have read a lot of mixed reviews on this as well. I own a laser thermometer now and didn't know what kind of readings I should be looking for on a 24 gauge single wall black flue pipe?

I apologize for the long list of questions and very appreciative of any members willing to share their experience and advice.

 

[brenndatomu]

If I go this route does is matter which orientation that 1/4 copper pipe is facing inside the pipe or how far it is in the pipe?

Doesn't seem to, no.
1. Looks pretty normal.
2. Ditto.
3. Sounds like poor workmanship...a little leakage won't help a lot if the power fails at the peak of the burn...a little, not a lot. And no, never really had that issue.
4. It really depends where you check it...you'll get different numbers whenever you move around.
I measure internal temps, and I see anywhere from upper 200's, to low 400's, depending on where I'm at in the burn process...general rule of thumb is that external temps will be about half of internal on single wall pipe. External on doublewall pipe doesn't mean much.

 

[Highbeam]

And don’t compare flue temps to the stove guys. These furnaces run the exhaust stream through a huge heat exchanger to strip heat out to super low levels.