My lawn sprinkler maintenance man came to turn on my sprinklers today, and informed me that 19 of my 45 or so heads have blown seals. After he left, I found an outdoor valve (back flow valve?) was leaking heavily. I had to close the master shut off valve for the system. He is supposed to discuss it with the office, and get back to me.

This company installed my system about 7 years ago. I have paid them to winterize it every fall, and turn it on every spring.

Like much of the USA, NJ had prolonged cold weather this winter. I am suspicious that the fall winterization I paid for may not have been done properly. I am wondering if water was left in the system, and it froze, blowing out the head seals and back flow valve. I don't yet know what the company is going to say.

So, here is my question. Do you think this large amount of damage to the system was likely to have been done by water left it the system to freeze?

Thanks for any opinions.