Hydrotech Membrane and Filters
It is recommended that they check valve and auto-shutoff valve be replaced annually. Hydrotech filter pack for a 4 stage reverse osmosis is one sediment 41400008 and two carbons 41400009 and should be changed every 6-12 months. Reverse osmosis membranes generally last 2-5 years.
Tanks need air annually using a bicycle pump or air compressor. The tank should have 10 psi when empty. Tanks should be changed every 5-8 years.
