Fuel quality needs to be monitored on a daily basis. This is usually done by taking samples from drain valves. There are 2 main types of drain valves that are commonly used:
- Apollo spring return valves – these are “deadman” type valves which spring shut when released.
- Ball valves – these are 2 way valves which also allow control of flow. Open and closed positions are at 90 degrees to one another.