I have a submersible pump for irrigation it is 1 1/2 HP at 100 deep and during zone changes the pressure relief valve pops and I have it set at 100 PSI now should I set it higher and what is the harm to the system and or the pump if I do. The other possible answer would be what can I do with the gallon or so water for the 8 cycles that the system has. Other than letting it spray into the air. It is really only a problem in the winter and it causes ice issues in the drive and neighbors yard. OOPS!
What happens to the pump if it dead heads for 20 seconds or so between cycles. Thanks.

You could probably solve your problem by putting a small pressure tank (10 gallon or so) on your system. It could "absorb" the additional volume between zone changes. Fairly cheap solution.

Would the tank need to be installed attached to the pressure relief valve or could it be on the downstream side? Where can I get on cheap. Would it need to be a bladder type of tank? What about freeze protection in the winter?

It would need to be near the pressure switch. I was thinking of something like this:

Sears: Online department store featuring appliances, tools, fitness equipment and more (http://www.sears.com/shc/s/p_10153_12605_SPM2043088101P?sid=IDx20101019x00001 e&srccode=cii_125121617&cpncode=00-18555835-2)

Would need to be protected from cold weather. What state are you in?

Thank I am looking for a cheap pressure tank. Do you have any sources?