Graffiti barrier

This type of sacrificial anti graffiti coating is similar to floor polish in that it forms a coating to prevent the paint/dirt being absorbed by the wall/floor.

Once painted its stripped off taking the graffiti with it. They do work fairly well, but its a continuous cycle coat/strip coat/strip coat/strip.

Commercial hot water pressure cleaners (single phase) operate @ up to 150 bar x 10 ltrs/min and reach around 90c. Fairly safe activity with a little common sense. However, they pressurise the water first, then heat it via a continuous flow boiler.

If you heat the water first, you have to keep the temperature below 60c or the pump will cavitate & wreck itself.

Your B&Q jobby is prolly around 100 bar x 6 ltrs/min and limited to 60c, so it won't work that well. You might find it difficult to remove the coating, which could look worse.

Might be easier just to use a graffiti remover if you get attacked, they are good if you get in quickly.

My DeltaJet pressure washer says 40C max water temperature. It uses the water to cool the motor.

Karcher have used water cooled motors for some time on their hot water machines, benefit being slight pre heating of the water prior to it being heated & the facility to use one end of the motor for the pressure pump & t'other end for the fuel pump & combustion fan.

Rare on cold water machines, Gerni introduced a 'hot box' machine in the

There are spray on graffiti remover products that work well. I've found that the best way to stop graffiti is to catch the little bastards. Around here they always use a vehicle (their own and not even stolen), and with my video cameras and still cameras I get their rego numbers and the police do the rest. Failing that, a dummy video camera with a flashing red light does keep them away.