Hot water tank plumbing/pump?

[Norseman]

Did a search, nothing popped up

Question: Stock 2001 Albin 28TE, 26 gallon main water tank and a 10 gallon hot water heater/tank:
Can you empty both of them at the same time?

Yesterday I drained 10 gallons using only the hot water faucet and it seemed the hot water tank was immediately replenished from the main tank.
Keep doing that and the main tank will be empty and the pump with suck air, but the hot water tank is still full?
To utilize the entire 36 gallons I would think a second pump is plumbed in there somewhere, and there is a way to separate the 2 tanks, a valve or something..?

I emptied the main tank a few days ago, but did not try to hot water faucets to see if the hot water tank would also empty.

So…..Can you empty both tanks and in effect utilize the entire 36 gallons?
If not, has anybody modified the plumping so as to use all the water onboard if needed?

[Pitou]

The way that our boats are setup and I don't know of any other that is different, once the main water tank is empty there is nothing left for the pump to push and evacuate the water in the hot water tank. Albin specs (in the document library) list the 28 capacity as 36 gallons, but usable is 30 'ish and is actually a little bit less. The stock hot water tank is 6 gallon.

The 31 specs say that the capacity is 72 when in fact the tank is labeled as 65 gallons and the hot water tank is 6 gallons. Seems like Albin counted 1 gallon in the pex tubing to come up with 72. Usable is truly a little bit less than 65 as when it's time for winter storage and I unscrew the inspection ports that I installed there is always about a gallon or so left spread across the bottom of the water tank.

Don't you just love marketing!

Every year at decommissioning I would need to manually drain the hot water tank on my 28 and do same now on my 31 by using the drain spigot on the bottom of the hot water tank. For us northerners, if we don't and you bypass the water in the hot water tank to winterize the rest of the system the hot water tank will freeze and crack the tank. Years ago a member posted of that happening to him .. lesson learned.

[Norseman]

. Albin specs (in the document library) list the 28 capacity as 36 gallons, but usable is 30 'ish and is actually a little bit less. The stock hot water tank is 6 gallon.

Just as I was afraid off.
The usable water in the main tank is actually 26: I used every drop in the tank, then filled it with a digital water meter, 26 gallons and no more..
(Hence I assumed the hot water tank would hold 10 gallons, but you are saying it is only 6)
There could of course be 4 gallons unusable in the main tank, just sloshing around depending on the trim of the boat: Is the pick-up aft, center or forward?

Oh well, nothing is as advertised.
Will have to take a long and hard look, see if there is a way to add a pump to the small tank, and a valve to isolate the tanks for normal use, then open the valve only for filling the hot water tank.

[Pitou]

On my '02 engine box a plastic tank was under the quarter berth deck hatch with the pump supply fitting coming from the forward lower starboard side corner of the tank.

Up here in the northeast, my hot water tank gets a fair workout washing dishes, hands and the taking of showers. It's always in use. Even when just hanging dockside one of the first switches to be turned on is the hot water tank's AC powered heating element .. the cocktail glasses need to be washed.

[Norseman]

. Even when just hanging dockside one of the first switches to be turned on is the hot water tank's AC powered heating element .. the cocktail glasses need to be washed.

Yeah, good idea to keep them cocktail glasses clean and ready to go.

We have a dock in the back yard of the house so all dirty dishes goes in the house, then in the dishwasher. We also use disposable cups, plates and cutlery which goes into a dedicated recycle bag onboard, then back at home base it goes in the City recycling container.
As can be seen from the above, we hardly if ever use or need the hot water tank.
Until now:
Installed an electric head with fresh water flush, hence our fresh water needs doubled. (Before installation I thought we had 36 galleons available, I was wrong, IT IS REALLY 26 Gallons… )

Back to the drawing board.

[Norseman]

. Every year at decommissioning I would need to manually drain the hot water tank on my 28

Do remember what the drain under the tank looked like?
1/2” threaded plug, or an Open/Close valve?
I could use the drain hole to plumb in a line and a pump to pressurize only the hot water lines, that way I can empty both tanks..

[Pitou]

The fitting was set into the tank with a Pex tubing connection on the other end that then went directly to the freshwater pump.

[Norseman]

. The fitting was set into the tank with a Pex tubing connection on the other end that then went directly to the freshwater pump.

The winterization drain was a PEX connection going to the pump…?

Guess we are talking apples and oranges..

[Pitou]

No drain. To winterize I just disconnected the Pex fro the tank fitting and slipped a piece of flexible hose that had the same ID that fit the Pex OD and turn on the pump to run the poly glycol throughout the freshwater system. I always bypass the hot water tank and just drain the freshwater from it and leave the spigot cracked. As far as "fully" draining the freshwater tank on my 28, there's no need.

[Norseman]

No drain. To winterize I just disconnected the Pex fro the tank fitting and slipped a piece of flexible hose that had the same ID that fit the Pex OD and turn on the pump to run the poly glycol throughout the freshwater system. I always bypass the hot water tank and just drain the freshwater from it and leave the spigot cracked. As far as "fully" draining the freshwater tank on my 28, there's no need.

Darn, I thought it was a dedicated drain for the cold winters in New York and New England.

Ok, back to the drawing board.