Air locking in mixer shower

[BINGO]

HI Guys

can any one help please.
Since having a custom made twin coil cylinder from Gledhill ( 1 side fed from solid fuel rayburn other gas boiler).
Pipework out of cylinder up 8 inch to tee, up for vent to cold water storage tank, across 16 inch before a tee down in 22mm pipe to bath, reducing to 15mm pipework across to another tee, down to kitchen taps and up into loft area for shower and down to mixer shower over bath.
Every day or every other I am constantly letting air out of bottom of mixer shower tap which gets trapped. Once released shower works fine!
Also I have noticed that when running any tap the vent pipework into cold water storage tank gets hot,

ANY IDEAS ITS DOING MY HEAD IN!!

 

[PlumbBobBob]

hi bingo any chance of a picture showing the pipe arrangement? sounds like you should have taken the feed from the horizontal pipe before it teed into the feed/vent.

 

[BINGO]

Hi Steve
will try to attach photo. but would an auto airvent work on shower pipework in loft area???