Raw Water Strainer

[Kim Efishoff]

Peggy,I have another question related to my last, entitled "Plumbing", submitted on 2/20/02. The same diagram that I referred to in my last question shows a raw water strainer installed at the intake on the toilet (which is good for all the reasons you have stated in previous correspondence and articles). But this RWS is shown mounted above the waterline (as if it were a vented loop), yet with no air vent.What good does it do to mount a RWS above the waterline w/o venting it? Won't a syphon get started under the right circumstances (e.g. if the intake seacock is open and a leak develops inside the pumping mechanism of the toilet)?BTW. The RWS on the seawater intake of my engine heat exchanger is located below the WL and has no vent. Is this a potential problem (e.g., if a leak occurs somewhere in the SW cooling system). Should I put a vented loop in this line also?Thanks again,Kim Efishoff

 

[Laura Bertran]

Vented Loop/Strainer

Peggy- As you advised, I'm installing a raw water strainer between the thru hull and the head on the water intake line. The head is below the waterline. Will a vented loop interfere with the the head's ability to pump if I'm also going through a strainer? Which side of the strainer would the loop be on? Thanks.Laura BertranRising Tide (H31 #514)

 

[Kim Efishoff]

Peggy,It's always a pleasure to ask you questions. You always reply right away, and your answers are authoritative and to the point. I will not put a vented loop on my engine saltwater intake or my head intake raw water strainer, and now I know why! Thanks, again.Kim Efishoff

 

[Peggie Hall/Head Mistress]

The strainer goes between the thru-hull and

the pump, Laura. The vented loop cannot go in that line...it has to go between the pump and the bowl. A vented loop between the thru-hull and the pump will interfere with the pump's ability to prime.