Originally Posted by WalterAtMarchPump
If you are getting cavitation then its usually cause by a couple things:
1. you have a restriction on the inlet side of the pump...either the line is too small or the fittings/elbows/valves etc are restricting the flow rate to the pump.
2. you have air trapped inside the pump. Turn the pump off for a second and let gravity try and purge any air in the pump head out...make sure the outlet is the highest point of the pump.
3. you may be sucking air either from a vortex being created inside your tank or a loose connection of the supply line.[/COLOR]
Hi Walter. Very cool that you're doing some Q&A.
I have an 809 and have been having trouble pumping boiling water. It works fine otherwise. I've had some people on the forum tell me that it was likely cavitation causing my problem. If that's true, I suspect this is due to the restriction caused by my dip tube. I plan to do a test run without it, so.....
Asuming the pump is primed, there is no restriction to flow, and the pump is not sucking "air" anywhere, it should be able to pump 212F water right? What if the water is at a state of rolling boil and water vapor is bubbling up pretty rapidly inside the vessel being pumped out? Could this perharps cause water vapor to get trapped in the pump head since I am not using a pressurized system? If I have the pump oriented correctly and water vapor does make it into the pump head while in operation, will the vapor continue up and out of the pump head or does the pump need to be shut off for this to happen? Lastly, you mentioned that higher temps adversely affect the magnets on the drive. Although I'm sure that I will never exceed the 250F ceiling, will repeated / prolonged exposures to boiling temperatures reduce the life and or efficiency of the magnets? If the magnets do get "damaged" can just the magnet drives be replaced (part number would be great) or does the whole pump head need replaced at that point?
Thanks in Advance.....again it's very cool of you to help us out with these issues.