The spray at the front end is dispensed via the heater box in the handle behind the light. This has a maze of narrow water channels which will get clogged up if dirty tank water is allowed to mix with the clean. Always run clean water through after use.
The heater box can be dismanled and cleaned by taking the wheel to handle part apart. Watch out for the small seal washers under each screw when the cover of the heater matrix is removed. Don' do it over the sink as I did. Some washers went down the drain & I had to recover them.
Reassemble & spray should be restored to the front. Spray from the wand does not go through the heater.
Fixit Lewis, December 2006