Solenoid mystery
Hi Y'all,
My zone 1 stopped working about 2 weeks ago. I have an older house so I assumed that the valve / solenoid had gone bad. I measured 28 V at the valve when I'd unplugged (and turned off) everything. I went ahead and changed the diaphragm and the solenoid (I bought a new valve and replaced the entire top section).
The valve did not turn after this. In fact, I didn't hear any noise at all when the solenoid is powered / unpowered. So I disconnected the solenoid - and interestingly, I discovered that I get 24 V when I disconnect the line from the solenoid, but barely 0.5V when the solenoid is still connected. I understand the solenoid draws current, but did not expect such a large voltage drop. When I test the (new) solenoid with an ohm-meter, I get 30 ohms of impedance, which I understand is the normal reading.
Does this situation make sense? After all this testing, I am at a loss to explain what I am seeing. I deeply appreciate your help,
Regards
Walker