Problem fixed! I replaced the valve - not the problem - did not think it was, but thougth it was an easy enough to try. I purchases a 100' roll of 1" poly and bypassed the inground line between the valve and the 1" line near the hose bib I mentioned in previous replies above. The sprinklers worked perfectly. The problem was an obstruction in that line. Now to fix. The line is a 1" poly that was already installed long before I purchased this home so I did not know where it was buried (and it was ...
Thanks for the suggestions. I will replace the valve. BUT - what explains the lack of pressure (input 75 PSI) when directly connected to city water with the connection of the city water directly to one of the heads? The valve is not even in the circuit.
Getting wierder! The valve has a "bleed valve" on top, a long thin metal shaft that goes down the center of the valve with a plastic knob on top. By turning this 1/2 turn you can operate the valve manually. The top of the valve is a faucet type handle so you can turn the valve on manually and adjust the flow just as one would on a faucet. I have the same problem if I use the valve fully open manually and using the system with the automatic timer. Now for the wierd= I installed a hose bib about 3...
This valve and all the valves in the system are: Toro 1" Model 53381. I installed the system 8 years ago.
Valve body is clean, no cracks, dirt, etc. All other components were replaced, seats, diaphragm, solenoid, etc. After this replacement - problem is still exactly the same. Pressure (as measured at a tap I had installed about the center of the run to the first head) is OK if the heads are capped. This is the only zone with a problem. Thanks for your interest. I am about to start digging. At a loss as to what else to do.
Thanks for the reply. Lake (LBJ in central Texas) is very good quality. All other zones works as they always did, most are the same or larger in size as 3. I replaced the entire assembly except for the body. Inspection showed no problems in the body. This system (& zone 3) has been working perfectly for 8 years. Today I capped all the sprinklers on zone 3 and took pressure readings. With all heads operational I have 10 PSI. With all capped I have 40 PSI. With 2 operational I have 25 PSI. Zone 3 ...
Thanks for the reply. This is why I am at a loss. All other zones work OK. (So not a pump problem) Zone 3 has worked great for the last 8 years (so not an installation problem) Leak test shows no leak. ( So not a leak problem) All sprinklers on the zone fail the same way ( So is a common poblem) I just replaced the control valve with no improvement. (Not a valve problem) What else is there? Mystery!
Thanks for the reply. This is why I am at a loss. All other zones work OK. (So not a pump problem) Zone 3 has worked great for the last 8 years (so not an installation problem) Leak test shows no leak. ( So not a leak problem) All sprinklers on the zone fail the same way ( So is a common poblem) I just replaced the control valve with no improvement. (Not a valve problem) What else is there? Mystery!
I have a 5 zone (lake pump) system. Has been working great for 8 years. Now zone 3 has very low pressure. Have done the following: Removed all sprinkler heads (5) and capped uprights - attached pressure gauge, turned pump on = great presure. Turned pump off and waited - pressure did not drop = no leaks! Reinstalled heads one at a time and checked pressure - one head = great pressure - as each head is reinstalled pressure drops. Replaced control valve = no difference. I am at a loss. Does not app...
