On Nov 21, 8:04*am, wrote:

Also, I agree with Ransley on the volume issue. * I can do mine with a
decent size portable shop compressor. *Not sure how big the tank is,
but it's one of the old craftsman horizontal tanks, with *2 wheels and
pull handle like a cart. * I can do mine OK with that, but I have 3
rotor heads per zone, maybe 5 smaller pop up heads on another zone,
etc. *I recently used it at a friends house and while we got through
it, I doubt I'd do it again. *He has a lot more heads, maybe 8 on some
zones. * It's very marginal, because there isn't enough volume. * On a
zone with 8, by the time you have 5 blowing air, so much volume is
being lost that it then takes a long time to get the rest of the water
out. * Even when I do mine, I have to let the compressor build up to
80-100 lbs, then turn on the zone. *I repeat that process until they
are clear. *On mine that is usually going through all the zones
twice.


Can you crank down the adjusting screws on all the heads and open them
up one at a time, then close it and move on to the next? Start
upstream and work your way to the end of the run.

Kinda similar to the way I winterize my cabin in Flagstaff, one faucet
at a time. Done it that way for 8 years, haven't had a problem yet -
except for the DUH moment when I blew the water heater empty without
remembering to turn if off first - burned out both elements, but the
pipes were fine.

Jerry