If your backflow device is above grade you should turn off the water and
remove it to a place that won't freeze (garage or crawlspace). If it is
underground, most people in my neighborhood just leave it in the ground;
maybe turn off the water at the pressure reduction valve and run a test
cycle to releave the pressure and drain some of the water.

Although my blackflow device is underground, I do remove it. It's the most
expensive single piece of the system (after the electronics), so it's cheap
insurance. In Durham, blackflow testing is required every spring, so I just
have the plumber re-install it.

No need to blow-out the system, even if it is just 4" deep; it just doesn't
get that cold in the Triangle (BTW, the standard for professional
installation is 8-12" deep).

Doc

"Doug Bradley" wrote in message
...
We bought a house this year, and it came with a sprinkler system.

It's a first for me, so can anyone please relate or point me to some
winterization instructions?

All I've been able to find so far are instructions which talk about
hooking up an air compressor and purging the lines. Does it get that
cold here to need that? Of course, I didn't put in this system so I
have no idea how deep the lines are (probably not very!)

Any suggestions welcomed.

tia,
Doug