Pressure Gauges
Pressure gauges are fitted to pressure washers so that you can tell firstly if the power washer is getting to the correct level and also to see if there is something going wrong, if the seals are going in the pump often the pressure gauge is the first place that you will notice any difference.
The pressure gauge can be mounted to the outlet nut on the pump (if there is a hole tapped and threaded there for it), the pressure gauge on some unloader bypass valves can be fitted on there, but many of the pressure washer manufacturers now mount pressure gauges on the instrument panel so that they can easily be seen.
When putting chemical on to whatever is to be washer it os often a good idea to lower the pressure to about half the working pressure before putting the chemical on as ofte on high pressure machines most of the chemical is blown back off before it has chance to do its job, please check with your chemical provider to see the best way to use there chemical.