I run one from tractor supply 25.00 bucks 200 psi max, it is just a 3 ported chemical resistant pressure regulator that when the pressure coming back from the spray gun is greater than whatever you have the pressure regulator set at it will overcome the spring and bypass back to the tank. Don't over crank it though because it just has a spring and a diaphram and if you overcrank it it will curl up the diaphram and start leaking but at that price I keep an extra on the rig. I went this route not so much for safety rather than I wanted to keep my pump running constantly throughout the whole job. I have been in Industrial maintenance for 12 years and one thing that I believe is that any motor is better off running verses turning off and on several times .Make sure you have a good hot battery before you start. I use Gel filled and never have any trouble.You can call me if you want 270-535-3882
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ALG Contracting Owner Chuck Drane Non Pressure Roof Cleaning Bowling Green Ky 270-535-3882 chuck@algclean.com www.algclean.com
Roof Cleaning Kentucky, Roof Cleaning Bowling Green, Roof Cleaning South Central Kentucky
On the delavan pumps there is no reason to have pressure relieve valve and you want the pump to cycle most guys here buy the demand pump these pumps are designed for intermitent running not continuous