Compressor to blow out sprinklers??

[GSB Ice Man]

I know its winter but, I need some info to make a buying decision.

What do you guys think is the smallest compressor a person should use to blow out sprinklers?? I sold my 60 gallon lunker and am going to buy a new one(smaller than 60 gallon)that sits vertical and has wheels.

Thanks in advance for your input

[CFRay]

I use a 30gal. craftsman to blow out my 8 zone system. Have used this for around 6-7 years and not had any freeze issues. Good Luck!

[Tom7227]

Wouldn't the answer depend on how the system was installed? I don't have one so I don't know the 'real' answer, but for instance if you have a low spot you may be able to get air past it while blowing it out but not enough to force all the water out of the system. Then it may just migrate down to the low spot and freeze. I see rigs being pulled around with the towable compressors and wonder if that's overkill, a way to get it done quickly so you can do more in a day and earn more money or what. BTW I think this has been posted before so if you do a search back on this thread you may find prior Q & A's.

[LwnmwnMan2]

Look down about 6 posts.

[setterguy]

Too many variables to answer accurately. Size of system, number of heads on each zone, size of pipe.

One key piece of advice, if you do it yourself with a small compressor let it sit for a day or two then do it again. With the small volume of air being pushed through the pipes it can appear that all the water is out when it is actually being pushed to the side of the pipe allowing the air to pass right by. What will happen over a day or two is it will settle in the lowest spot causing potential problems in the spring.