You can increase the pressure from your tinaco by increasing the size of your PVC downpipe. There is a lot more resistance to flow in a long 1/2" pipe than in say 1-1/2" or 2". Especially if there are a lot of elbows in it.
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Exactly, I've mentioned this before. The only downside to a 2" pipe is if your hot water source was on your roof (solar) then you would be using the large amount of water (about 2 gallons) standing in the supply pipe before ever getting to the hot water. But still very do-able.
To help with the 45 degree elbow problem, you could use 45 degree long sweeps. I can't wait to try it.
..............................................WATER FLOW RATE IN GPM.............................................
...................... ..................................Pipe Diameter in Inches............................
length, ft........0.5.......0.75........1.........1.5.........2.........2.5.........3..........4..........5............6
....5................23........66........140.......407.......868.....1560......2520....5371.....9659......15,601
...10...............16........45.........96........280.......597.....1073......1733....3694.....6643......10,730
...15...............13........36.........77........225.......479......862.......1393....2968.....5337........8620
...20...............11........31.........66........193.......410......738.......1192....2541.....4569........7380
...40................7.........21.........46........132.......282......508........820.....1747.....3142........5076
..100...............4.........13.........28.........81........172......309........500.....1065.....1916........3096