Water temperature fluctuations while showering - Beneteau Oceanis 40

[AFKASAP]

I have added air to the accumulator as mentioned. It was due a top up. However I still get the fluctuation in water temperature. I will continue to troubleshoot on Monday.

Beneteau Oceanis 40 - 2008
Netherlands

[ontoso]

Hello,

I have exactly the same problem on my Benetau 40 from 2008.

I tried everything with the accumulator but nothing changed, did you manage to solve the problem?

[AFKASAP]

Originally Posted by ontoso

Hello,

I have exactly the same problem on my Benetau 40 from 2008.

I tried everything with the accumulator but nothing changed, did you manage to solve the problem?

Hi there,

No I have not found a solution yet. I may try to change the tap as some people suggested.

[tuffr2]

The set-up you have looks just like a camping RV...I have this issue of I do to have all the winterizing valves set correctly. On my campers there are multiple in-line valves to by-pass the water heater when winterizing. If in the spring I do not have the valves set right I get the water temp fluctuations.

Now...knowing which valves need to be opened or closed is not going to be easy unless they are marked well.

Sent from my SM-G360V using Cruisers Sailing Forum mobile app

[ontoso]

In a few weeks I will be in the boat, I will try to find the problem, I will keep you updated.

[TeddyDiver]

As a former plummer.. It's a problem with pipes. Small diameter and long runs add a lot of pressure drop on the way to shower. When the hot and cold water tubing have different pressure drop this is what happens with accumulator/pump run ons and offs. Get bigger pipes, check the length and get a shower head with lower water flow ..

BR Teddy

[AFKASAP]

Thanks guys. I will test with a different shower head as well.

[justsail]

Hi

I had this issue on my Oceanis 50. Very similar setup to the photo's in the early part of this thread re: Oceanis 40. I replaced the pump and accumulator (Johnson originals installed by Beneteau) with an all in one Jabsco VSD pump which resolved the issue.

You can see my write-up of this on my site in my discussions section on justsail.net

regards
Paul

[ontoso]

I fixed the problem on my Ocenis 40, I changed the water pressure pump and problem solved.

[dlymn]

the old pump might be OK as a deck washer or to wash down the anchor when you lift it. I have a small pump as well as the big bilge pump. The big one is there to manage the big stuff and the little one is a 'sweeper' to keep the bilge dry. They have their own float switches , intakes etc. A spare pump might be useful in these ways and it keeps it on the boat if the new one has problems,

[unclemack]

Accumulator set pressure should be about 2-3 psi below pump's cut-in pressure according to Jabsco's info.

Johnson Flowmaster pump pressures are on page 12 of their manual. They forbid pressure adjustment but it looks like it could be done by trial and error. Tank looks to be in the way on your photo though, need to remove the pump from the mounting board.
Some pumps let you choose cut in and cut out pressures. Least difference means faster cycling but more constant pressure.

Bigger accumulator (mine's 24 litres) does reduce the number of temperature changes by reducing the number of pump start/stops during a shower but best option is thermostatic temperature control valve as others have recommended.

https://www.jabscoshop.com/files/Acc...4%20doc595.pdf

http://www.spxflow.com/en/assets/pdf...Flowmaster.pdf

[wsmurdoch]

I installed a Watts Series USG-B M2 Under Sink Guardian Tempering Valve in the hot and cold lines feeding the shower. I adjusted the temperature set point to the water temperature my wife wanted to shower, which is quite hot. She opens only the hot tap on the shower to get the water temperature she wants; I add a little cold. It has been in place for two + years now and works well. It prevents scalds when the hot water has been heated by the engine and is nearly boiling. I have twice had to remove the hot water supply line to clean a small inlet screen which plugs with lime flakes from the water heater. Other than that, no problems.