Mag 18 - Advise Needed

[DBlackman]

kaiser, I was concerned about 'back-pressure' too, along with preventing 'Stress fractures' known to be experienced with Mag pumps.

I am using two (2) 1-inch 'T' in the 'Return' line:
a. The 1st 'T' directs flow to the CA Reactor, which has a Ball Value to prevent too much pressure on the CA Reactor.
b. The 2nd 'T' directs flow to the Chiller and is 'unrestricted'.
c. The rest of the main flow hits the SWID, before returning water to the tank.

I figured that the 2nd 'T' line to the Chiller would prevent back-pressure from occurring, but I am not plumber.

[kaiser]

Every T added will create more back pressure. Mags are very sensitive to that. I've read somewhere that for every t or elbow in the line is dropping the flow quiet a bit.

[DBlackman]

kaiser, Yes, I was made aware on the use of 'elbows', to include other factors on flow restriction. But the insight on the use of T/s and PVC/s or plumbing in general, were not to use materials that are smaller then the outlet of the pump being used. I figured that using 1-inch tubing and 1-inch 'T's' wouldn't be a major factor... unlike the 3/4 inch fittings on the SWID. When I take the Mag 18 out for cleaning, I will check it's condition. If there are stress fractures, then I will need to put the SWID on a separate pump or something. Just don't want to add additional electrical equipment.

[kaiser]

Does anybody here have experience with Mag 12s used as external pumps?

[tomanero]

I'm a big fan of fans blowing across the water surface for cooling.

I read in 2 other posts that because of the humidity people were having overheating problems this past weekend. Haven't had that experience myself but who knows.

[alton]

I used a mag 18 on my 75 for years but only as an external pump and never had any heating issues. But in saying that Marine Depot will not warranty mag drive pumps if you use them externally.

[DBlackman]

Hey alton, that's great information. Thanks!