First, make sure the valves have silicone tubing in BOTH sides of the valve. This is required for the valve to work properly.

If this does not solve the problem, then try lubricating the valve. Place a small drop of mineral or 3-in-1 oil to the front of the valve when it is compressed. Then cycle it several times to distribute the valve. (Try this with only one valve at first!)

If this does not solve the problem, then we'll want to examine the valve controller as a source for the error. Call our tech support for a test procedure.