Always get a qualified person to do the work . I knew a guy who changed an electric shower four times in one week. He insisted he had power because the lights came on. When I put a meter on the terminals in his shower he had 35 volts ( some issue will the pull switch) He had enough voltage to make the lights work but the elements required 240volts. He worked all week for nothing. If the low flow light is coming on. Despite the fact you may or may not have good pressure in the home , the shower is telling you it is not getting it. The unit has a service filter Check the instructions and have the unit serviced by a qualified or competant person. Good Luck
Alan, December 2008
