Noisy Taco FloChk Valves

[velvetfoot]

I've noticed a noise that sounds like air bubbles coming from the first floor baseboard. After doing a few things like raising the system pressure, draining some water, and throttling the various isolation valves, I got an automotive stethoscope today. I'm almost certain the noise is coming from the Taco 218 FloChk valve. If I move the valve some when it's running it makes a similar sound and the noise seems to be greatest near the valve. I noticed that when the other zone is running, even though I don't hear the noise in the house, I hear it in the basement, located and amplified by the stethoscope.

Now that I know what it is, I'm not that worried about it, but I wonder if there is something that can be done about it.
(PS: The circ loops are driven by Taco 007s.)

Thanks

 

[ewdudley]

A Taco 007 on a single baseboard loop is quite likely over pumped. Try calculating your feet per second according to the Taco sheet: (broken link removed to http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf) .

Over pumped is more noise. Taco promotes their newer Flo-Chek as being quieter: "A unique, re-designed weighted check on the 221 and 222 models features an enhanced heating and quieter operation on high flow systems.", so there apparently is such a thing as a noisy Flo-Check.

Your problem will likely go away when the new Varios are in place and you can adjust flow to be slower.

 

[velvetfoot]

Thanks EW. I've been messing around a lot with the Taco HSS program. I'll read that Taco sheet at some point, .
Anyway, HSS is saying:
1st floor: 3.2 gpm flow/6.7' head loss/1.9 fps velocity
2nd floor: 2.8 gpm flow/12' head loss/1.7 fps velocity.

Looking at the pump curves, below, as far as gpm goes, yeah, way more capacity. What gets me is head. Is that head loss I'm reading on the chart, because the 007 only goes to 10' Or, does 'total head' mean something else, because I'm working with 12'. Now, the pipe lengths were pretty roughly estimated, but I might be misunderstanding something fundamental.