hard breathing with my DAAM

[ducky]

So i went to pool today to field test my DAAM and i find it very hard to breathe when i am in horizontal trim.. like really hard

This makes me to review if my rebuilt procedure has gone wrong somewhere..?

My daam setup includes phoenix, HPR, DBE, new diaphram and DSV. IP set at 145psi, and i adjusted the second stage nut till slight hissing with the exhaust can on then back 1/8 turn to remove the hissing.. so am i doing this correctly? as i don't really feel the venturi effect of breathing here

I have serviced a lot of conshelf in the past and also 109 with Bryan's balanced adjustable kit.. and i think my 109 breathes a lot better than my DAAM .. any input here?

[ScubaLawyer]

Perhaps regulator positioning? See

viewtopic.php?f=12&t=2119

I set my Phoenix IP at 135 but I'll leave it to the experts on here to say if your 145 makes any difference.

Is your DSV open all the way?

My 2psi.

Mark

[rhwestfall]

What are you using it on (BC/Plate/Simple Harness)? The further off your back (shoulder blades) the can is, will likely decline performance....

[Herman]

Is the HPR in the correct position? It should be screwed in all the way then backed off until the first of the larger holes is pointed directly at the feed horn. This will be somewhere from a few degs of rotation to almost 180 deg . The 2 smaller holes should be in line with the 2 screws. Is the HPR lever installed correctly? It should be pointed up with the forks around the IP adjustment screw. The levers feet should be between the 2 washers and the rounded edges of the washers should both be against the lever feet. Normally I have to back off the nut more than you describe to get the lever height correct. There should be some space between the diaphragm and the plastic tips of the lever with the reg pressurized. I find 1/16 or a little more to be about right.
The only other thought is you somehow have the wrong spring in the HPR.

If it's really really hard to breath with little flow, are you sure you have the mouthpiece check valves installed in the correct orientation ? the check valve (mushroom) should be inside the mouthpiece on the supply side and out of it on the exhaust side.

An IP of 145 is fine, a little higher than I run but its' not a problem.

One off the wall thought, was the valve on the tank fully open and did it have enough air pressure? If it breathes OK on the bench, orientation will not have that much effect on it.

[captain]

Check for a partially stuck mouthpiece inhalation valve. Has happened to me.

If the regulator hits the back of your head when horizontal or slightly head down it is too high. It needs to be tight to your back between the shoulder blades.

[ducky]

Perhaps regulator positioning? See

viewtopic.php?f=12&t=2119

I set my Phoenix IP at 135 but I'll leave it to the experts on here to say if your 145 makes any difference.

Is your DSV open all the way?

My 2psi.

Mark

yea DSV opened all the way.. tried with both on and off position

What are you using it on (BC/Plate/Simple Harness)? The further off your back (shoulder blades) the can is, will likely decline performance....

i am using DIR harness with DIY AL backplate with no groove so it rests quite flat on my back with regulator can and i purposely adjusted my harness to longer so it will stay at my shoulder blade area..

[ducky]

Is the HPR in the correct position? It should be screwed in all the way then backed off until the first of the larger holes is pointed directly at the feed horn. This will be somewhere from a few degs of rotation to almost 180 deg . The 2 smaller holes should be in line with the 2 screws. Is the HPR lever installed correctly? It should be pointed up with the forks around the IP adjustment screw. The levers feet should be between the 2 washers and the rounded edges of the washers should both be against the lever feet. Normally I have to back off the nut more than you describe to get the lever height correct. There should be some space between the diaphragm and the plastic tips of the lever with the reg pressurized. I find 1/16 or a little more to be about right.
The only other thought is you somehow have the wrong spring in the HPR.

If it's really really hard to breath with little flow, are you sure you have the mouthpiece check valves installed in the correct orientation ? the check valve (mushroom) should be inside the mouthpiece on the supply side and out of it on the exhaust side.

An IP of 145 is fine, a little higher than I run but its' not a problem.

One off the wall thought, was the valve on the tank fully open and did it have enough air pressure? If it breathes OK on the bench, orientation will not have that much effect on it.

thanks for the idea Herman.. i suspect something wrong with my assembly procedure as well.. i will remove the HPR today and see if it helps any.. the funny thing is it breathes well when in vertical.. but terrible when i am started going into horizontal position, but this is my first time diving double hose so its all quite new to me. Tank valve was fully opened at 3000psi. That was what i thought so too, i have read all the pdf documents by posted by Bryan at VDH site but i didn't expect it will be so hard in breathing like almost turning the air off

Check for a partially stuck mouthpiece inhalation valve. Has happened to me.

If the regulator hits the back of your head when horizontal or slightly head down it is too high. It needs to be tight to your back between the shoulder blades.

ok thanks cap will check my valve and see if its any FOD..
now that u mentioned it, i have a feeling that my harness is quite loose, but not to that extent of hitting my head when im head down.. i have no way to check that since i don't have a camera with me underwater

[Herman]

Properly against your body, the orientation does not make a huge difference- good to really bad but it does make some. Is it possible your BC was floating ? I had a friend borrow my reg and commented on how bad It was. I knew the reg was working very well so I couldn't figure out why he was having so much trouble until I saw his photo. He was wearing a loose jacket BC with a good bit of weight on his belt and air in the BC. The tank was floating 4 to 6 inches above is back and he was basically suspended from the BC. You could see a gap between the tank and his back through the BC. That will make a DH reg breath very badly but won't affect a single hose like he was use to.

[ducky]

Properly against your body, the orientation does not make a huge difference- good to really bad but it does make some. Is it possible your BC was floating ? I had a friend borrow my reg and commented on how bad It was. I knew the reg was working very well so I couldn't figure out why he was having so much trouble until I saw his photo. He was wearing a loose jacket BC with a good bit of weight on his belt and air in the BC. The tank was floating 4 to 6 inches above is back and he was basically suspended from the BC. You could see a gap between the tank and his back through the BC. That will make a DH reg breath very badly but won't affect a single hose like he was use to.

i was using my diy backplate with DGX 25lbs wing although it was a bit loose but the movement was horizontally.. i could feel my backplate still touching my back whole time..

I also reassembled again the HPR second stage today and partial blocked one of the smaller orifice to increase venturi effect.. may i know your regulator when u drawing ur breath how does it feel? mine feels like require quite a bit of effort and need to inhale a lot in order to feel the extra air pressure coming down to my lungs, is that normal? for example with the 109BA i can inhale small sip and i can feel the air is already rushing into my lungs.. which is quite opposite with the DAAM