320 DA Water Heater not delivering hot water from manifold

[beeyacht]

Usually when the engines are warm, my hot water tap delivers hot water as it is warmed via the engine manifold. Now it's not doing it anymore. Played around with some valves but still no warm water.

Any ideas? Thank you.

 

[markrsimon]

starting with the basics.. assuming that the hot water tank is full of water, and when you open the faucet on hot - water does come out, but not hot water? Are you running the boat out in the water, or warming the engines at the dock? Need maybe an hour or two of running the boat to heat 6-11 gallons of water. Also, depending on who/how the engines were winterized - you can bypass the water heater. Can you look at the water heater and see 2 regular water lines connected (cold in, hot out) and 2 other heater hoses from the engine block? Post a picture if you can. The valve you adjusted - may be a mixing valve - which mixes cold water with the outgoing hot water to lower the water temp. Most of these hot water heaters have a single temp set from factory which is very hot. Finally - do you get hot water when using the electric heating element built into the water tank? A cautionary note : make sure the tank has water in it, and water flows from the hot water faucets, before you turn on the electric heating element. The element can burn up if there is no water in the tank for it to heat.

 

[Lazy Daze]

Adding to the above... check the two hoses that come from the engine. Disconnect both at the engine, look for clogs at the fittings. Then, blow through one of the hoses to see if the pathway is clear. It's possible the internal heating coil is clogged, especially if the boat is used in saltwater. If so, this is an end of life thing.

 

[beeyacht]

Usually when the engines are warm, my hot water tap delivers hot water as it is warmed via the engine manifold. Now it's not doing it anymore. Played around with some valves but still no warm water.

Any ideas? Thank you.

starting with the basics.. assuming that the hot water tank is full of water, and when you open the faucet on hot - water does come out, but not hot water? Are you running the boat out in the water, or warming the engines at the dock? Need maybe an hour or two of running the boat to heat 6-11 gallons of water. Also, depending on who/how the engines were winterized - you can bypass the water heater. Can you look at the water heater and see 2 regular water lines connected (cold in, hot out) and 2 other heater hoses from the engine block? Post a picture if you can. The valve you adjusted - may be a mixing valve - which mixes cold water with the outgoing hot water to lower the water temp. Most of these hot water heaters have a single temp set from factory which is very hot. Finally - do you get hot water when using the electric heating element built into the water tank? A cautionary note : make sure the tank has water in it, and water flows from the hot water faucets, before you turn on the electric heating element. The element can burn up if there is no water in the tank for it to heat.

Thanks for the reply Mark. Cold water flows freely from the hot water tap which should mean the tank has water in it. I attached a pic of the hot water heater. Must be a valve that was shut down during winterization but can't figure out where. Water should be flowing to the manifold as it always does.

 

[beeyacht]

Adding to the above... check the two hoses that come from the engine. Disconnect both at the engine, look for clogs at the fittings. Then, blow through one of the hoses to see if the pathway is clear. It's possible the internal heating coil is clogged, especially if the boat is used in saltwater. If so, this is an end of life thing.

Thanks, I'll look into that. I'm all freshwater, so that might help!

 

[Lazy Daze]

That pic doesn't show us much, though - there are things in the way.

 

[Shenanigans77]

To me....that tank looks bypassed from winterizing from that picture

 

[markrsimon]

To me....that tank looks bypassed from winterizing from that picture

I would agree.

At first I thought the incoming blue cold was tapped (with white hose) to feed the mixer. Looking at it closely - you can see its directly connected using the gray check valve which is normally on the hot side of the tank.

Q: Who winterized the boat?

 

[beeyacht]

Thanks to you both. Oddly, it was winterized by the same guy who has been doing it for the past 10 years. He's so busy right now it's 3 weeks before he can get to my boat - thus the post. I will keep investigating. Thanks again.

 

[pyro]

I had the same problem this year. While I don't think this will help you since your not in salt, maybe it helps others. Issue for me was a complete clog at the inlet and outlet of the hot water tank. Shoving a screwdriver in both inlet and outlet and flushing it out with a hose freed everything up. Luckily it seemed salt wanted to clog right at the fitting connection in the water tank. If it had clogged inside the pipe, there probably would have been no way to clear it. Now water is nice and hot!

 

[markrsimon]

Thanks to you both. Oddly, it was winterized by the same guy who has been doing it for the past 10 years. He's so busy right now it's 3 weeks before he can get to my boat - thus the post. I will keep investigating. Thanks again.

If you can get a better picture, Im sure you will see two open fittings on the tank. Chances are the blue line goes to the fitting on the lower right (cold in), and the white with the gray piece to the fitting on the top left (hot out).

I would not turn on the electric heating element. While water is flowing from the faucet while turned to hot - its most likely not going through the tank - as the hoses (in and out) are connected together.