Accumulator/GHS10/overflow sump

[Chimo]

I posted this in Cruises as a follow up to Roche. My apologies to those who are re-reading it but I thought it might be of interest in this forum as well.

"First thanks to Barry who showed me the accumulator installation. I went ahead and installed the Shurflo unit. My local yacht shop recommended that one over the Jabsco even though it was a tad more expensive. (I wasn't buying from him so no conflict of interest.) This was a really great mod.! The water flow has smoothed out and the pump is cycling nicely rather than being forced into a rapid chatter mode.

Second to Curt who showed me the GHS10 installation with the small block of wood addition to angle the handset slightly toward me at the helm. This handset change is great. I can see and control what is going on with the radio but also hear better.

Both mods. can be seen in our album. There is also a picture showing the overflow sump. This came up from a couple of people. As the HW tank heats up, either from heater or engine, the contents expand and have to relieve somewhere. (You can leave water pressure switched off and a faucet open as the HW tank heats up but I usually forget, or forget to close the faucet before I turn on water pressure.) Absent any other route the pressure relief valve will let about a cup or so of water escape. Once the water is hot then this will obviously stop. My issue was that this cup of water flowed through the locker (wetting contents) to the transducer location and then back through the drain hole under the locker bottom to the next drain hole down into the bilge. This latter hole is above the hull bottom on our boat so about 1.1/2 liters would accumulate before it drained. I hate resting water even though it is under the locker floor and I didn't like the idea of the water system reaching the 6 bar relief point of the tank. I simply took a clear tube off the PR valve and into a plastic box which acts as a sump. I know have to remember to empty that sump every 4 or 5 trips but I seem to be good at that."

 

[YukonRon]

Our R25sc has access holes about 2'' square cut through the side of the port and starboard storage lockers into the engine compartment. I'm not sure if they are from the factory or later modifications. The port side hole has wires through it, but the starboard side is empty. It looks like an easy fix would be to run a longer hose off the pressure relief valve, through the access hole, into the engine compartment and dump into the bilge. It passes through right by the seacock, at the level of the storage compartment floor; so downhill all the way.
I haven't had the boat long enough to notice any issues with this, but I'll probably do this fix anyway. One less thing to worry about.

 

[stwendl]

I have actually the same problem with the hot water tank pr valve. The stubby pipe that was attached would flow into the stbd locker under the electronics. First thing I did was to extend that pipe into the small defend where the depth sounder is located on my 2015/16 r27. Over time I noticed water accumulating even so the water heater was not on that often. My boat is stored under cover and rain is not an issue. The drainage is really not working well in that area. Tempted to cut an access hole in the floor for inspection and cover it with a screw on 6” panel. Not sure what is below to do that safely. But for now the pr outlet has been routed through that same 2in hole into the bilge directly. Will have to see how this works out in terms of accumulation of water in that area

 

[Chimo]

Over time I noticed water accumulating even so the water heater was not on that often. My boat is stored under cover and rain is not an issue. The drainage is really not working well in that area. Tempted to cut an access hole in the floor for inspection and cover it with a screw on 6” panel. Not sure what is below to do that safely. But for now the pr outlet has been routed through that same 2in hole into the bilge directly.

Thanks for the interesting comments. The PR valve will still relieve when the engine is run as the hot water will rise to a higher temperature than with the electric water heater. I don't have that 2 ins hole into the bilge, hence the reason for the plastic sump you can see in the photo. Let me know if you cut the hole in the locker floor and what you find please.

 

[ixlr8]

Thanks for the interesting comments. The PR valve will still relieve when the engine is run as the hot water will rise to a higher temperature than with the electric water heater. I don't have that 2 ins hole into the bilge, hence the reason for the plastic sump you can see in the photo. Let me know if you cut the hole in the locker floor and what you find please.

I was wondering if you have the accumulator/pressure tank, will the PR valve still open when the water heater tank gets hot? I am guessing the system without an accumulator has no place for pressure to build when the water tank gets hot. But with the accumulator, you should now have room for the expansion and the accumulator should adsorb the pressure and the PR valve should no longer relieve the 'excess' pressure. Unless there is a check valve between the accumulator and the hot water tank.

 

[Admiral S]

I added an accumulator to my boat the day it was delivered. I can say that with a 32 psi precharge in the accumulator that the hot water heater pressure relief still leaks as water is heated. Seems that the expansion does not have room to expand in the accumulator/pump/lines and still exits the PR.

I have installed a hose that feeds into a small container that I empty once in while. This way my stuff in the locker isn't sitting in overflow getting moldy and wet. (Copied the container idea from Chimo 🙂 )

 

[Chimo]

Greetings Admiral

Since both boats are 2017 I am assuming we have the same hot water heater. The PR valve on mine is a 6 bar unit so at 87 psi that is well above any pre-charge pressure in the accumulator. Is your set up for the container like mine (see photo in album) or have you found something neater from which I can learn?

Thanks

David

 

[Admiral S]

Greetings Admiral

Since both boats are 2017 I am assuming we have the same hot water heater. The PR valve on mine is a 6 bar unit so at 87 psi that is well above any pre-charge pressure in the accumulator. Is your set up for the container like mine (see photo in album) or have you found something neater from which I can learn?

Thanks

David

I copied your container the other day when I saw your post and photo 😛

 

[NautiTug]

Do you know what size connection did you connect to your water heater discharge pipe?

 

[Osprey]

I wonder about the 32 psi pre-charge pressure mentioned by Admiral S. I have installed a Par accumulator model 30573-0000, capacity 1 liter. The specified pre-charge pressure for this accumulator is only 10 psi. Perhaps the difference is due to a different model accumulator. In any event with my installation the pressure relief valve on the tank never opens. Just as well since the tank relief opening pressure is much too high for the hoses and connections installed in our tugs. As an exercise in caution I have also installed an adjustable in-line pressure relief valve at setting of 60 psi. So far the accumulator has prevented the system reaching 60 psi or more.

 

[Chimo]

Do you know what size connection did you connect to your water heater discharge pipe?

With apologies for the slow response.

It's difficult to see from the photograph in my album but I found a simple plastic connection to the PR valve. It is a standard garden hose fitting to the valve and then accepts, if my memory serves me correctly, 3/8 inch plastic tubing on the output side. [I can't measure since I am not at the boat]. Let me know if you need exact details and I will measure next time I'm down there.

It really does work well. Today I was winterizing the water system and after running off all the fresh water through the faucets I simply clicked open the PR valve by turning it through half a turn and the remainder from the hot water tank drained into the plastic sump so I could throw it overboard.