There are a lot of petrol operated and diesel operated pressure cleaners available on the market today and the noise levels of the machines vary drastically.
We are always asked about how noisy some of the machines are as people are concerned about the noise level in residential areas.
Petrol powered pressure cleaners whether they are hot water or cold water units will always be the noisiest units that you can use, as the dba rating of the petrol engines are around 89 dba if not louder. Then there are the diesel engines and these also vary. A lot of pressure cleaners that are manufactured or brought into Australia have air cooled engines and some are single cylinder engines as well. These engines are also very noisy with a dba rating nearly as high as the petrol engines used on pressure cleaners.
If you work at night or in a residential area when you are working, the quietest engine to use is a water cooled engine and to get a longer life out of the engine would be a 3 cylinder as the noise level / dba rating for these types of engines are around 79.6 dba.
You can get specialized engines that are quieter and are around 59.6 dba @ 3mtrs away but of course they are very expensive as well, but you will find that the noisiest part of a machine with a silent pack engine on it will be the water hitting the ground and not the actual machine.
We have also found that water cooled diesel engines will also last longer than an air cooled engine.
Although air cooled engines and petrol engines are a LOT cheaper then water cooled diesel engines, you end up saving money on repairs to the engine and replacement of the engine as well.