Originally Posted by jbell36
this is exactly what i was thinking, but i wanted to ask because i'm usually wrong...on this particular system we have 7 heads on two of the zones and i can guarantee you we could put another 7 on...you can't even push the head down with your foot...we didn't design the system, but we did renovate it...the issue is it's on a huge hill and years ago when the house was first built the builder didn't backfill or pack the hillside properly and there was a landslide...i didn't find this out til later, because the design of the system made absolutely no sense, but when they told me this it all clicked...there was 40' of swing pipe at the bottom coming up at a 45 degree angle to compensate for the pipe/heads that slid down the hill...one lateral was only half way across the hill, so we had to install like 100' or something like that just to complete the system...
anyways, i was thinking while i was there how i would have designed the system knowing it was a 5/8 meter and knowing there is 90 psi...it just makes more sense to me that if you are able to put more heads on a zone that will cover adequately then why not...i just figured i would ask just in case there was something i didn't know about that i would be doing wrong
If it is a new neighborhood, i usually try not to max out gpms. Also keep in mind you lose/gain a 1/2lb of pressure per foot of rise/decline.
And on a long pipe run to the backyard you are going to have some pressure loss if it is 1" pipe. So if you are running 7 heads with great pressure right at the meter, then try to do the same 200' behind the meter and up an incline you could have a problem. I always try to be conservative... keeps me out of trouble and leaves the option to add a head in the future.