Chem Meter Help

I have a Judson TNT and the chem meter (Dwyer meter) won't stay on a given flow rate. The meter after a couple of minutes goes down to 1 or less GPM flow rate, usually 1/2- 1/4 GPM.. The water box filter is clean, Cat pump was just rebuilt and holds great pressure, new filter and check valve in chem jug, just replaced all hoses to the meter and even replaced the meter. I looked for obstructions in the system and nothing. I am still having this issue and can't figure out why. Any suggestions?

I know dumb question, but is the adjustment knob real easy to turn (there should be some resistance on it), as it could be from vibration?

Nothing more frustrating than a cranky chemical draw system (my butler haunts me every year).

It sounds like you replaced about everything! It sounds like there is an air leak somewhere...often small cracks in the meter itself, but you already replaced that, so I guess that rules that one out.

My advice is to elevate your jug higher than your pump. Maybe it just can't always pull the chem against gravity on a consistent siphon. It helped me a lot on two of my tm's over the years and my new jug has the hose running from below it like an IV bag....let gravity help keep it primed.

must be an air leak somewhere. call Les, I was having minor issues with mine on the TNT and him and I got it figured out pretty fast with a phone call.

Check the hose barb where the hose connects to the flow meter ie replace and check the bushing on the meter. Use thread lock to seal. Also use a bright light to shine in the meter while looking for cracks they will show up in the light.
Seems like I remember on some of these units they used a check valve near the water Bx connection that may be malfunctioning. The one in the chem jug is a foot valve.
One other thought if the flow is good then drops off check for debri in jug clogging the screen I'm sure you've looked but you could try a clean bucket of water just to see. Just afew things to think about.

Thanks for all the help guys. I've done everything suggested except elevate the chem jug. I wanted to make sure I wasn't missing anything , I guess I'll call Les.

do you have an on-off valve if so check for air leaks on the valve it self

Any vacuum leaks at all in that system will shut you down. I chased mine for months before finding all of them on the butler. The great thing about elevating the jug is that you will be relying on gravity to pull the liquid instead of vacuum.

It sounds strange and no, you shouldn't have to, but it will often solve your issue if not the source of the problem.

gtech12v wrote:do you have an on-off valve if so check for air leaks on the valve it self

No separate valve, just the one on the meter.
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The meter doesn't seem to suck air when set @5 gph. It does get a lot of bubbles in it when set @ 2 gph. If you look at the picture above, right below the adjustment knob on the brass valve is the little hole where the flow is set. That is where the bubbles are coming from. I talked to Les at Judson and he thinks I might have got a bad replacement valve. After pulling everything back apart and resealing all connections it has improved. It takes longer to bleed down and so far hasn't dropped below 1 gph.

I'm going to go buy a vacuum tester and see how the system holds and hopefully pinpoint the problem.

Sounds like a bad meter assy. Or at least the metering valve o rings need repair.

I think Eddie^ may be onto it.

Replace the o-ring on the stem behind the black knob.

I sealed the threaded portion of that stem with teflon tape and no difference. I looked for o-rings today and had no luck. I'll do some testing tomorrow if time permits.

Hey Eddie, do you know where to find o-rings around Fayetteville?

When my o-ring was shot I also tried the teflon tape around the threads trick but it still pulled in air until I replaced the o-ring. An air leak (as I'm sure you already know), is a suction/chem injection killer every time!

Can you see where the o-ring is obliviously 'flat spotted'? If so, it's very likely where your air leak is.

Check with sunbelt. Ask for a rebuild kit for the metering valve. Also I've been told lowes has a good assortment of O rings if u take the old one they may match one up.

Dunno 'bout over there, but my local ACE Hardware has a great assortment of hardware including o-rings.

Davey Cracker wrote:When my o-ring was shot I also tried the teflon tape around the threads trick but it still pulled in air until I replaced the o-ring. An air leak (as I'm sure you already know), is a suction/chem injection killer every time!

Can you see where the o-ring is obliviously 'flat spotted'? If so, it's very likely where your air leak is.

I can see on my old meter where it is flat spotted, but on the new meter it looks perfect. I even lubed it up with vaseline like it tells you to do in the Dwyer instructions.

by ACE Services on Thu Dec 18, 2014 12:04 am

Check with sunbelt. Ask for a rebuild kit for the metering valve. Also I've been told lowes has a good assortment of O rings if u take the old one they may match one up.

Sunbelt told me they don't have rebuild kits for the meters. I'll check Lowes. Thanks.

Another temporary thing that might work is to flip the o ring, sometimes it works, sometimes it doesn't, worth a shot if the o ring is almost new like in your situation.