I have a triton HP combi shower which has been workin for 10 years but performace was fallen off. So a triton engr fitted a new cartridge. Result no hot water, low pressure ,Bosch combi boiler light does not light when shower is operated, but will supply hot water through bathroom sink tap Engineer blames boiler. But shower did operate with original cartridge. Any suggestions?

D S Beech, February 2010

Are you in a hardwater area?
check to make sure that shower outlet head is not scaled. Does the combi fireup when the showerhead is removed (just the hose allowing blended water to flow out), This seems like an insufficient flow through the cartridge caused by a blockage in the blended water outlet

garryk, February 2010