snowmelt

Paul S_3

hey everyone ....i posted about this system before ....im designing a snow melt system using the "WIRSBO snow & ice melting design manual"....i have it pretty much complete btu sqft load=95....supply water temp 115f....9'' on center....total load 82,000btus...6 loops at 190 ft each....leader length 20 ft....so total loop length from manifold is about 210 ft....im using a 30% mixture of prop glycol....flow per loop is 1.14 GPM...there are 6 loops so total system flow is 6.9 GPM....Head press drop per foot 0.02143ft head multiply by 210 longest loop length = 4.5ft head.....i will be using 5/8'' pex for tubing....my question is should i be using 5/8'' pex? i know flow per loop is 1.14 gpm  which is suitable for 5/8''but is that correct? i found head loss in 5/8'' pex with 30% glycol charts....also the piping to the manifolds need 6.84 gpm should i use 1'' copper ? system is based on a 25f delta T ....and i have the ft of head for the longest loop (4.5ft hd)but for proper pump sizing how do i add the amount of head loss before and after the manifold?   thanks PAUL S