sounds like you have trash in a valve or a bad valve. if turnign the sprinlers on for a few minutes does not clear it, then the zone valve is bad and needs to be repaired or replaced.

dt, Sound like you have good pressure for your purposes except when you mother in-law is doing laundry or watering her plants. check the flow rate by filling a 5-gal bucket and record the time to fill. You are splitting your flow rate from the street with her when you are both using water. If your mainline from the street is 5/8" which is common for subdivision (1" for upscale homes), I assume your house is 60 years old, so you have a reduced size of piping to about 1/2" diameter(from scaling). This size give you about 14 gpm. You can verify this by the filling bucket method. If you have a demand from a 3/4" pipe while gardening and you and your MIL uses water you may experience lower pressure. To establish what that pressure is use a pressure gauge(cheap at Hardware Store) on a hose bid to monitor the pressure. I would put a 1" pvc to the beds to reduce pressure loss and go from there. Each fitting and regulator you install saps pressure, but you should be okay. You can always irrigate one bed at a time if necessary. A little wordy but hope this helps. JMHO Aloha

What you describe sounds like the washer in the stop valve being loose. Since you changed the valve,that is ruled out. There shouldn't be another valve upstream in the line but it's worth taking a close look anyhow. I assume you inspected for obstruction in the tube between valve at wall and fill valve.

A wet bulb of 63°F at 74 RA is close to 50%RH; NOT 55%; the indoor Delta should be 18 to 19°F; NOT 14°F. Where was the indoor delta taken? Edited: The SuperHeat (SH) at 90°F ambient Edited: with fixed orifice is on target at 10°F. (I had Misread SH chart) Subcooling (SC) is on the low side. Perhaps Evaporator could be absorbing a little more heat, but the only thing off is the 14-F indoor split.