Flow too slow ?
Comments
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This is not a Taco problem unless that pump is defective which is highly unlikely when new.
You have a restriction somewhere. Get a 20 or 30 PSI guage and connect to a garden hose adapter. Move it around the verious ports on your loop and measure the pressure when running. This should be able to point you where the restriction is. That 007 is currently running almost dead headed so there should be 5PSI more than your expansion tank pressure just after it.
That mixing valve looks to be a DHW one, they tend to be restrictive. What is the CV on it? If that is the issue, you can remove it and adjust temperature by reducing the flow of the 006.
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Taco 5003-C3 Mixing Valve is a dual-purpose mixing or diverting valve that delivers fail-safe security and superior performance. The ASSE 1017-approved valve provides shut-off reliability on either a hot or cold water supply failure. Its high flow and low headloss make the Taco 5003-C3 mixing valve ideal for applications such as domestic hot water, radiant heat applications, installations with large variations in flow rate and supply conditions, and installations that require precise control of water temperature. Mixing valve's unique design ensures a stable and controlled mixed water temperature throughout the extended 85-176°F range.
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Others with there own, but everyone has advice but not necessarily all the data., this is what I have. And thanks
Taco 5003-C3 Mixing Valve is a dual-purpose mixing or diverting valve that delivers fail-safe security and superior performance. The ASSE 1017-approved valve provides shut-off reliability on either a hot or cold water supply failure. Its high flow and low headloss make the Taco 5003-C3 mixing valve ideal for applications such as domestic hot water, radiant heat applications, installations with large variations in flow rate and supply conditions, and installations that require precise control of water temperature. Mixing valve's unique design ensures a stable and controlled mixed water temperature throughout the extended 85-176°F range.
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there is pressure drop involved with y strainers. Brand new off the shelf, completely clean they have pressure drop😗
If in fact that one was intended for domestic water use, with a tight mesh spacing, it will be adding to the pressure drop of that circuit. It’s an easy test to remove it.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream0 -
I'll do that right now..
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I removed it, it made no difference..
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The 5000 series is incredibly restrictive, but with only 4 loops, should not be causing the issue you're seeing. Something else is restricting flow, so I will ask one more time: is this a glycol system or straight water? Are you absolutely positive that all 4 flowmeters and all 4 white knobs are cranked all the way counterclockwise? Strainer screen is definitely a possibility, and you should pull the check valve out of the circulator while you have the system opened up as well- it's not serving a purpose.
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Where is the mixing valve in relation to the pump? suction side or discharge side of the pump? (pumping toward the mix valve, or pulling through it?)
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Straight water, yes valves open on manifold, check valve removed, strainer screen removed. The temperature gauges do restrict some but This much ?
Could it be the heat exchanger ?
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I have seen pros with 20+ years under their belt not purge air correctly on occasion, how did you purge the air from the system?
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I used an external pump , pumped water out of a bucket and into the bucket from the discharge until air stopped coming out. The pump is very quite, I know the sound when air is in the system..
And the air eliminator has burped a bit of air out as well.
I have to go for a few hours, be back later and can do some testing with a gauge like suggested.
Thanks for all the help guys !!
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I said the direction seemed strange to me, is that My problem ?
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If you are not scooping water and pushing it that's a problem.
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Well then I will have to call Taco when I get back.
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Circulators do not "scoop" they water, they paddle or slap :) it through.
Fluid enters the center, eye of the impeller, centrifugal force flings the fluid out to the discharge.
I've never heard of the vanes being backwards, the arrow on the volute casting is the direction the fluid wants to travel, regardless of how the impeller vanes look to you.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream1 -
Ok thats good.. thanks,
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Hello Bob,
We both know the issue is water movement. Resistance to flow creates pressure. What I am saying is the counterclockwise rotation of the volute is the problem and I believe this why it is not pushing hot water through the loops even though the impeller casting is of very close tolerance to the volute vanes.
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It is pushing water, and what are the odds it was manufactured wrong, is that even possible?
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I wrote Taco, see what they say, we have eliminated everything but the Heat Exchanger.
I don't think that's a problem as it's working fine on the other side.
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A plugged exchanger is certainly a possibility, though VERY improbable on a new system unless you had a whole mess of debris or flux in the system. Did you isolate each loop one at a time when purging, with the valve between the two purge valves closed tightly? Filling on the right and draining on the left? Did you see any flow on the flowmeters during that purge phase? If yes to all of the above, maybe move your purge pump and hoses over to the drains on the manifolds themselves and after isolating the manifolds from the rest of the system, try it again purging only the floor loops.
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Yes to all the above, I could try that, also I used water soluble flux.
Yes I believe I did see flow on the gauges using the other pump but I really wasn't paying attention to it.
If there was air wouldn't I hear it ? I have it the past, the pump is very quiet now.
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If there's no/minimal flow, no you wouldn't hear the air because it's stuck in the floor loops. Moving the purge to the manifolds themselves and purging each loop individually (pumping into the supply manifold with the flowmeters) for 3-5 minutes each will eliminate that as a possibility and verify whether or not the flow issue is within the manifolds/tubing or the rest of the system.
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I think it would be rare to see an impeller that manufactured in the reverse patten. Or a motor spinning the wrong way?
A partially plugger HX is certainly an option also.
If you slowly close down the red handle valve on the manifold you should hear the flow going through as it gets restricted. That tells you the circ is spinning and moving some fluid.
The arrow on this circ is pointing the correct way.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream1 -
Ok, I will do that tonight, thanks
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Taco wrote me back , the direction of the impeller is correct.
Because our 007-F5 slings the water and not scoop, the imp will spin opposite the direction of the flow arrow on the casing Hope this helps.0 -
What is the make and model for the mixing valve? do you know the cV value for it?
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In this example the impeller as you look at it is spinning clockwise. Flow is going from left to right. I'm not sure how you would call the flow since it goes into the center of the impeller and is sent out the right port. I guess I would call the direction CW also? This graphic is more about cavitation, but it shows the inside look of a circulator.
Regardless of the terminology, hydraulic equilibrium is established in a hydronic loop within seconds of the power being applied. ECM take a bit longer to wake up and get up to speed.
Keep looking, if the impeller spins, the 007 is doing what you paid it to do.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream1 -
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Did you find some air? What are the flowmeters showing now?
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The sure thing is to get a pressure gauge with a hose adapter on it and move it around from drain valve to drain valve until you find the restriction.
@Kaos mentioned this several posts above. It's the closest to a sure thing as you're going to get. Without that you will continue guessing.
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I'll never know, I had to replace a damaged gasket on the mix valve so ..
1/4 GPM each loop so no big change, but the numbers aren't too bad and thing are warming up.
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any idea how long the loops are? That is yet another thing that could cause low flow.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream0 -
I did, system pressure set at 15 psi, I measured 15 psi everywhere I looked except the manifold supply side where it measured 18 psi.
And I can't believe just five hours ago it was 64*!and now it's almost 70*. And the slab is not even saturated yet.
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Yes the loops are 200 feet x4
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Something is still screwy here. That system with the components used should easily be flowing double that, likely closer to triple. "Good enough" might be just that, but something is still not functioning properly.
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I'm out of ideas, I could send drawings to Taco and have them look to determine if the pump is the reason, already talked to them about it.
It's s either the pump or the mixing valve, there are no other restrictions.
Furthermore Im thinking my loops may be more like 250 feet each.
I'm all ears if you have any ideas.
And how do we know the flow gauge is correct…
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Have you thought about taking a control valve out of the manifold to see if the manifold might be gunked up?
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