Taco Zone Valve Question

I have a taco zone valve on a supply line. Can I safely cut the pipe after the zone valve and add in a ball valve if the taco valve has no power to it. In other words, can I assume the taco valve closes 100% as the norm (are these valves quality enough to assume this?) with no power applied.

Simple answer NO. You will still have pressure from the return side.

John

John,

Thanks for the quick reply. Didnt think about the return side, but this line does a 90 with a drop of 7 ft, so I assume water loss will be minimal with this to equalize (didnt explain this though in original post).

Any thoughts on the valve though?

If you will not get water from the "return side" then you will not get any from the supply side either, regardless of whether it is open or closed because both sides will have equal pressure, the valve just stops flow. Normally, you would put the ball valve in front of the zone valve, but why are you doing it anyway?

Follow up:

There was no flow, as per hj. Lost about a cup of water from the line when cut, as expected. Ball valve inserted.

Taco Zone valves, depending on type (I think I have the 571s) have the following specs, so had I read this I would have known:

Taco Zone Valve 571-2 3/4" Features:

Normal Flow Rate - 4 1/2 to 6 GPM
Volts - 24V / Amps - 0.9
Equalivent Feet of Pipe - 20
Pump Head Feet of Water - 65
Maximum Working Pressure - 125PSI
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