Winterize sprinklers


  #1  
Old 08-25-11, 08:45 AM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
Winterize sprinklers

I had underground sprinklers installed in 2005 and every October the guy comes and blow the system dry with a compressor he has in a truck. The 1st year it cost me $70 for this job which took him not more than 10 minutes. Second year the price went to $90 and the 3rd year was $110.

The last few seasons I didnít use the system because we had a very wet summer but this season I use it only once and then the city put a ban on watering the lawns and I didnít use it again

The system consists of a total of 18 sprinkler heads divided in 7 zones and we are talking the longest leg to be not more than about 150 feet. I have a 2 gallons 100 psi compressor and I was thinking to blow dry the system myself. I know that with a 2 gallons compressor it may take some time to do the job but Iím retired and I have the time. To my opinion it can be done if I do one zone at a time.

What do you think?
 
  #2  
Old 08-25-11, 06:41 PM
mike1059's Avatar
Member
Join Date: Jun 2011
Location: usa
Posts: 64
Upvotes: 0
Received 0 Upvotes on 0 Posts
one zone at a time is how it is normally done. once you have the fittings to connect to the system close the main shut-off, open the first valve either manually or by the clock then start the compressor and cycle through the zones.
 
  #3  
Old 08-25-11, 07:56 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,704
Received 662 Upvotes on 562 Posts
I blow mine out using a 20 gal and that works fine. 2 gallon compressor is not a lot of air but might get the job done. You will have to take a lot of breaks to let the compressor catch up.
You could likely get a used bigger compressor for the cost of 1 or 2 years of blow outs on craigslist. You could also pick up a air tank and put it in line with your compressor to get you more volume.
 
  #4  
Old 08-25-11, 08:25 PM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
Tolyn thatís a good info, thanks

I would love to have the space for a 20 gal one but your idea for an air tank, which I though, is an easy way out and thatís what I will do
 
  #5  
Old 08-27-11, 06:16 PM
S
Member
Join Date: Sep 2008
Location: Long Island
Posts: 695
Upvotes: 0
Received 0 Upvotes on 0 Posts
just let the pressure build up to what your water pressure is coming in onto the house and cycle the heads if zoned..can you disconnect the main water feed going outside to let the balance of the water drain out
 
  #6  
Old 08-27-11, 07:37 PM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
Originally Posted by sminker View Post
just let the pressure build up to what your water pressure is coming in onto the house and cycle the heads if zoned..can you disconnect the main water feed going outside to let the balance of the water drain out
Dont really understand what you mean but yes the system has 7 zones selectable from the main panel. No way to drain the water by gravity
 
  #7  
Old 08-28-11, 12:31 PM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
I try to figure out the air volume in my sprinkler system in order to determine the approx. volume of the air tank I need.

So my 2 gallons air compressor is about 0.3 cubic feet

One of the zones in my sprinkler system is 120 feet and the pipe diameter is 3/4", which I figured is about 0.33 cubic feet.

Anyone can tell me if the above are correct?
 
  #8  
Old 08-28-11, 06:02 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,704
Received 662 Upvotes on 562 Posts
I think you might be over thinking it a bit. You just need to hook up the air line, open the zone valve and then open the air valve. The air will push out the water. You don't need to know the cubic feet of pipe because the heads will be spewing water as fast as the air rushes in. Also the compressor may be .3 cubic feet but that would be the volume at atmospheric pressure. Your compressor is about 120 psi. If you really want to calculate it you need the CFM.
 
  #9  
Old 08-28-11, 06:53 PM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
The rental place has 2 size air tanks so if I know the approx. volume of my pipes I can get the right size tank. If I get the largest tank I may have my small compressor working overtime for no reason
 
  #10  
Old 09-16-11, 06:29 PM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
I had a chance today to blow my underground sprinklers and I need your opinion.

The rental places do not have any more compressed air tanks and so I had to try to do the job with my 2 gallons compressor. With a setting of 75 Lbs and working one zone at a time, it pushed the heads of the zone up and the water started to come out for about a minute and then I heart the hissing sound of air coming out from each head along with a lot of drops of water. Finally the air run out and the heads went down still hissing a bid and lots of water droplets around each head. Repeated the same for each zone with the same results. Doing each zone for a second time produced the same results Ė the heads go down with a lot of droplets of water around them and a lot of air coming out.

My conclusion is that the pipes are empty of any water, or almost empty, but the droplets of water around the heads bother me. I plan to do the same work tomorrow and go around on each head with a piece of rag to try and soak out as much water droplets as I can. To my opinion, if there is any small amount of water left inside the pipes, when this water freezes it will not damage the pipes because the small amount of water will have the space to expand since the pipes are not full of water

I donít know the internal construction of the sprinkler heads and Iím asking if the water droplets which may have stayed inside the head will break the head when the droplets freeze up.
 
  #11  
Old 09-17-11, 06:12 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,704
Received 662 Upvotes on 562 Posts
Minor droplets shouldn't cause any problems as they will just dry out in a day or two. Any water left will drain down back tot he lines. As you mentioned, the leftover water will freeze, but since it is not full is will not damage the lines.

You could unscrew the heads, shake them out and reinstall them, but I don't think it is worth the effort. I don't think one drop will break the head. But these are not my heads.

Sounds like everything worked OK with the small compressor?
 
  #12  
Old 09-17-11, 07:18 AM
kolias's Avatar
Member
Thread Starter
Join Date: Jul 2004
Location: Canada
Posts: 1,609
Received 7 Upvotes on 7 Posts
Yes my little 2 gallon compressor did a good job although a 5 gallon one would have been ideal. Also never noticed any difference between the short and longer zones; I was expecting the heads in the longest zone (about 300 ft of 3/4" pipe) not to go up but they did and lots of water was pushed out until the air started to hiss out.

As you said Tolyn not worth it to remove the heads but I will go around the second time with a sponge and mop out any water droplets.

But I donít think I will ever use my sprinklers again. This summer we had a complete ban from the City Hall on watering the lawns and all the ones in the neighbourhood went brown but with the first rain fall we had they all became green as ever. So why bother, let the nature take care of it

Thanks for the help
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: