At this point they are considered incertae sedis;in other words, we know that they are theropods; and probably coelurosaurs; but we don't know who they are related to or how they fit into the big picture of theropod phylogeny.
Idle speed is adjusted by means of the idle control valve, which is a solenoid-operated valve that is generally automatically adjusted by a computer. One problem that can occur with this component is a loss of power (from a severed line or a short) but a more common problem is simply dirt and grime.
A master valve is a single valve located at the water source that can shut off all the flow of water into the irrigation system. For more details see my article on master valves. On systems with a pump you will probably want to shut off the pump.. Make sure you have a really good quality spring-loaded check valve on the irrigation mainline pipe. The check valve goes someplace after the pump, but before the pressure switch. A good quality check valve is needed to keep the water from leaking backwards out of the system through the pump.