I have installed a Satellites shower unit to my gravity fed hot water system. I have commissioned it according to the fitting instructions but there is no spray force when I turn it on. What should I check?

Check that you have installed the correct type of mixer unit. It must be a low pressure unit not a high pressure unit. This detail is on the rating label on the mixer unit. Check that the purge pin is in the off position in the control panel. Check that air is not present in the water supplies to the mixing unit or the mixer unit itself. Check that the mixer inlet filters are not blocked.