System Design Decisions - Pressure Tank, Relay, Pressure Switch, Valve Placement???

I have read alot about designing your own system and I think I am ready to tackle it but I am in sort of a dilema. From what I can tell, there are two basic ways to set up your valves and pump.

First of all, I am pumping from a canal about 15 ft lower than my pump. I have been deliberating on putting a pressure tank on my line and letting a pressure valve control the pump operation or using no pressure tank and letting the irrigation controller control the pump with a relay.

I want to place my valves near each zone so that I may manually control the valve if there is a problem without walking all the way around the house, plus I avoid the loss in running smaller line from the valve to each zone with having the valve at the zone.

I really don't want to use a pressure tank because they are ugly and expensive but I still want to have the valves at each zone. I don't want to turn off the valve and have the pump overheat because the irrigation controller is running it. I am thinking of putting a relay for the irrigation controller and a pressure switch in series with the relay so that even if I turn off a valve, the pressure would build and turn off the pump. The also allows you to save the pump from overheating if a head becomes clogged, etc...

Will this work? Does this sound like good logic? Has anyone done this before?

I would appreciate any feedback on a system set up in this manner.

Thanks.

 

Without a tank, you can not use a pressure switch.

An irrigation controller can turn on the valves and the pump at the same time if you have a pump start relay. Problem is, if the valve does not open the pump will run deadhead for the duration of that zone.

Fifteen feet is a pretty good lift for any above ground pump, jet or centrifugal. You will lose efficiency. A submersible would be a better choice.

bob...