Harman Measuring Draft: 3/8-16 to 3/8NTP or 1/8 Tubing adapter.

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
L

lawlopez

New Member
Sep 22, 2008
56
New Boston, NH
I have a Harman P61 pellet stove.
I have a Dwyer Magnahelic .5 inch vacuum/pressure gauge.
It has 3/8 NTP fittings.
It comes with 3//8 NTP to barbs for 1/8 ID tubing.

The Harman has a bolt closing up a place to connect the 1/8 tubing.
It's location is not found in the P61 manual but the P38 manual.

This bolt seems to be threaded 3/8-16

How do I connect a 1/8 ID to it ?

I'm at a loss unless I just push the tubing into the hole without a fitting.
I suppose I could do that and temporarily calk it in place.

The basic problem is that 3/8-16 sould not be used for an air/vacuum port.
Thanks,
Larry
 
3/8-16 thread uses a 5/16" drill.
you just need to put the 5/16" tube into the tapped hole and this is sufficient to check draft.
most dwyers come with a silicon hose 1/8" id and 5/16" od just dont leave it in there too long.
 
Larry Lopez said:
Oh my.I hadn't even thought of using somehting that could take heat !!!
Thanks a lot.
Click to expand...

You don't need to check the draft when it is hot. The draft readings in the manual are for a cold stove.
 
Yup.

I wanted to see if there was much change when it was actually running.
I foundsome tubing which worked pretty good.
It was 5/16 OD but 1/4 ID so I removed the fittings from the gauage.
And used it with no fittings at both ends.

I welded the tube I used to the stove and couldn't get it out !!!

I got it out by using a torch on the inside.
Didn't take much. Just a touch. Came out clean.
I was cracking up. What a dummy.

I have a lot of draft.
Always more than .5 inches.

How do you adjust it ?
There is nothing on the control board.
 
I have a p61-a that has a small opening for a straight screwdriver to adjust combustion blower speed.
Mine would not get below .56 at low draft.
If you have this adjustment it is to the right of the ignitor statis light.
Set feed to test, turn on stove,pellets feed for 1 min then stops feeding.
Combustion blower will alternate from low to high draft every 1 min or so.

I have set my meter up also while running.
I drilled out another bolt and attached copper tubing to it.
I used about 18" of tubing and coiled it.
Hooked up therubber tubing that is about 3' long.
The gauge works fine during operation.
I keep the gauge about 4' from stove on the floor off to one side.
 
My P61 has the hole in the sheet metal.
It has a place on the circuit boad for adjustment.
It doesn't have the adjustment device soldered to the printer circuit board.

Your P61A is adjustable, my P61A is not adjustable.

Did adjusting it down decrease the feed rate on low settings ?

Good job on the copper tubing.

Larry
 
Status
Not open for further replies.

Similar threads

J
Cannot find draft test tube on Harman P35i
Replies
5
Views
623
The Pellet Mill - Pellet and Multifuel Stoves
jeffreybcox
J
Don2222
HF Air Polisher with 1/4x20 fine thread hole and new polisher pad kit has 5/16-24 fine thread shank! How can this work?
Replies
2
Views
817
DIY and General non-hearth advice
Don2222
Don2222
Ocelot
Harman P43 install - Will 2" outside air kit restrict flow at all or do I need to go with 3"
Replies
5
Views
2K
The Pellet Mill - Pellet and Multifuel Stoves
bogieb
bogieb
Ocelot
Meat my new (to me) Harman P43 I just finished overhauling and customizing.
Replies
7
Views
2K
The Pellet Mill - Pellet and Multifuel Stoves
Ocelot
Ocelot
F
Adding a manometer/magnehelic gauge to a flue pipe
Replies
22
Views
5K
The Boiler Room - Wood Boilers and Furnaces
JRHAWK9
JRHAWK9
Top Bottom
Back