Converting CW 30 head to fresh water.

[BB marine]

Solenoid/ Valve is necessary. The pressurized fresh water line goes to the head. The solenoid /valve is used to turn the water flow on to the head when actuated and turn water off when not actuated. You could use a manual ball valve in place of the Solenoid/valve. Hand operate the flush water.

 

[ixlr8]

Solenoid/ Valve is necessary. The pressurized fresh water line goes to the head. The solenoid /valve is used to turn the water flow on to the head when actuated and turn water off when not actuated. You could use a manual ball valve in place of the Solenoid/valve. Hand operate the flush water.

Thanks for this info, guess I need to add another item to my list of parts before I get started. I still have some time as the boat is still covered with snow and ice.

 

[quinsky]

I went the easy, cheap route on my C 28. I installed a shut off valve to the head intake at the strainer. Now I use the fresh water spigot from the sink to fill and flush. I worry about contamination when connecting the fresh water system to the head. Germs can get around check valves.

 

[BB marine]

I went the easy, cheap route on my C 28. I installed a shut off valve to the head intake at the strainer. Now I use the fresh water spigot from the sink to fill and flush. I worry about contamination when connecting the fresh water system to the head. Germs can get around check valves.

Patrick, I had the same concerns before converting Raw to fresh water. There are some opinions that say there is a possibility of contamination. I had that opinion too. When I spoke to the representative from Raritain I asked him about this concern. His first question was " is your fresh water flush in your home attached to your common freshwater system ?" My answer was yes, but there is a tank to separate. His comment to that was " we include a vacuum breaker in the kit that is installed on the top of the head where the water discharges for flush, this separates it." There is also a positive close valve (solenoid valve) and water pressure on the down stream side of the valve." The components are designed to stop cross contamination. Do they ? I excepted his explanation. Your method guarantees no cross contamination. Honestly I'm not worried about it, and we use our fresh water system for drinking water.It is a valid concern. I will be the first to post don't do this if I get sick! :shock:

Did you remove the seawater pump from the head? I don't think it will hurt to run dry because it is an eccentric driven diaphragm pump. The advantage of removing it if you are not using it for seawater flush is the head makes 75% less noise when flushing (my opinion) The eccentric driven pump makes most of the noise while flushing.

 

[jkhiser]

On Wenniway, the prior owner just moved the head suction from the raw water strainer to the suction side of the fresh water pump. The head pump draws from the FW tank through the original SW vented loop. You do not need the fresh water pump online to flush the head.

 

[BB marine]

On Wenniway, the prior owner just moved the head suction from the raw water strainer to the suction side of the fresh water pump. The head pump draws from the FW tank through the original SW vented loop. You do not need the fresh water pump online to flush the head.

I'm not sure how that works. It does because you are using it. I question the plumbing sequence. The Vented loop has to be on the pressure side of the pump. If it is on the suction side it will suck air and not pump. The biggest issue with having a fresh water flush is the chance of getting cross contamination from the head to the freshwater system. Not likely but possible. The only separation from toilet bowl and freshwater system is the Loop installed. If the previous owner installed the loop 2' feet above the head ( fresh water pressure side to allow separation ) and a check valve between the suction line of the head pump and suction side of the freshwater system pump. If the loop vent is working properly and the check valve is seated 100% this should allow enough separation from your fresh water system and the head. There needs to be a positive barrier between the head and the fresh water tank with redundancy to help eliminate cross contamination. The kit offers this, Vacuum breaker, block valve (solenoid) and system relies on water pressure all maintaining a positive barrier.

 

[quinsky]

Brian, Thanks for the info. My concern for contamination comes from being a healthcare provider 😀 No I did not disconnect the raw water pump. I confess that my knowledge of the head is lacking. I need to do a little research. I took the path of least resistance.

 

[jkhiser]

Brian - good questions.

I am more than a year into this boat, correcting prior owner mods, and now I guess I need to add the head to the list of things to examine and prolly correct. Just yesterday I finally got the bonding system back to complete configuration. Still got all sorts of weirdness in electrical system to ferret out.

As far as the supply vented loop, it remains on the outlet of the SW (now FW) pump on the head. The pump just sucks from the small FW tank instead of the big SW tank.

It seems fairly unlikely that contaminated water could work back through the vented loop to the FW tank. I have seen no evidence of a check valve. Of course, I have not examined for one either. If there is not one, I will prolly add a solenoid isolation valve.