▁in ▁the ▁US . ▁ ▁Elect ro - h yd ra ul ic ▁– ▁the ▁motor ▁drives ▁a ▁hyd ra ul ic ▁p ump , ▁which ▁press ur izes ▁the ▁oil ▁in ▁a ▁door ▁closer , ▁which ▁in ▁turn ▁turns ▁the ▁door ▁closer ▁and ▁opens ▁the ▁door . ▁This ▁is ▁the ▁preferred ▁type ▁in ▁Europe . ▁( In ▁the ▁US ▁it ▁has ▁a ▁reputation ▁of ▁being ▁pr one ▁to ▁oil ▁le aks .) ▁ ▁Elect ro - p neum atic ▁– ▁the ▁motor ▁drives ▁an ▁air ▁compress or ▁and ▁may ▁be ▁located ▁away ▁from ▁the ▁door . ▁The ▁air ▁pressure ▁is ▁used ▁to ▁drive ▁the ▁operator ▁above ▁the ▁door . ▁This ▁type ▁is ▁not ▁common , ▁and ▁noise ▁can ▁be ▁a ▁factor ▁if ▁compress or ▁is ▁located ▁close ▁to ▁a ▁door . ▁Typ ically , ▁the ▁compress or ▁can ▁be ▁located ▁up ▁to ▁ 2 0 0 ▁feet ▁away ▁ens uring ▁that ▁noise ▁is ▁not ▁a ▁factor . ▁ ▁A ▁typical ▁life ▁expect ancy ▁of ▁a ▁p nea um t ic ▁system ▁is ▁ 1 0 – 1 5 ▁years ▁except ▁the ▁compress or . ▁Best ▁application ▁of ▁a ▁p neum atic ▁system ▁is ▁in ▁a ▁resident ial ▁environment ▁where ▁usage ▁is ▁limited ▁to ▁ 3 0 – 4 0 ▁times ▁a ▁day . ▁ ▁Of ▁the ▁elect rome chan ical ▁types , ▁two ▁approaches ▁are ▁used : ▁Dis eng aging ▁– ▁the ▁motor ▁driven ▁mechanism ▁( the ▁op ener ▁portion ) ▁is ▁not ▁joined ▁to ▁the ▁closer , ▁but ▁only ▁eng ages