A properly installed sprinkler systems has drain valves to make sure
that there is no standing water in the pipes. However, many installers
save time and money by leaving these out. If water is left in the
system you may have a problem. In 30 years in Dallas I never had a
problem. In my other home with a 36" frost depth, it is another issue
altogether.

The issue with blowing out the system is that you need air volume more
than you need high pressure. I large diameter air hose and fittings
help. It's similar to the problems that you'd have trying to "pop" a
tubeless tire after installing it on the rim with a nail gun compressor.

RB


Thomas Kendrick wrote:
BTW, what is the reason for blowing out a sprinkler system? In 13
years in Texas, I have never done so. I have repaired it several times
due to driving over a line or damage while planting a shrub.
What would be the benefit of doing so?
Leaving water in the lines is not usually a problem since my lot has
significant slope and the excess drains out of the lowest head.


On Wed, 21 Jan 2004 17:22:56 -0700, "Chris Shearer Cooper"
wrote:


How do I know if the compressor I bought to power my finish nailer is strong
enough to blow out my brother's sprinkler system?