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Bay Hose Sizing

Mr. Clean

Member
Is the pump going to be happier and live longer the larger the hose between the outlet and bay boom or is fitteng size the determinant factor? Have two locations - one using 1/4, one 5/16. Have never considered the difference previously but have to replace a 5/16 and only have 1/4 on hand.
TIA
MC
 
I have 1 wash that is 1/4" and one that is 3/8" I have noticed no discernable difference on pumps, Pump maintenance etc. The main difference i have is on high pressure functions the changeover time is less on the 1/4" vs 3/8"
 
What size tips and pressure are you guys running? I'm speculating more pressure loss at the tip with the 1/4" but maybe some of you can test this.
 
I use 3/8" but 5/16” is the sweet spot for changeover time and not excessive friction loss in the longer runs. I tried 1/4" and I felt the loss was too great. I was having to dial up pressure to 1600 at the pump gauge to get 1000 at the gun. You could use 1/4” from manifold to trigger gun to speed up changeover time.

Looking online it appears that with a #6 nozzle@1000 psi (3 GPM) 1/4" hose loses over 40 psi per 10 ft. , 5/16" loses 17 and 3/8" loses only 7. I’ve got one wash with an equipment room on one end and my furthest bay is a 120 ft. run. Add in miscellaneous losses from the bay manifold, swivels, etc to that and you can see where 1/4” is pushing it , especially in longer runs.
 
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I used three eights for everything. It seems to work well for me. I've only got two ss bays though, and changeover is about 6 to 7 seconds for chemicals. Nobody complains about that.
 
3/8" from pump to bay manifold, then 1/4" to the gun.
I should clarify, this is what I do - only 1/4 from manifold to gun. 3/8 for pump to bay. Running a 2505 tip set at 1200psi at pump - like this combo and customers come to our wash due to better pressure than our competitors
 
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