What is wrong with this water heater installation?

Observations?

Black wire is pinched behind the cover?

Rafe

The hoses from the heat exchanger do not appear to be double clamped?

The T & P valve is plumbed "somewhere" it needs to be free flowing.

Ken

Additionally, several hoses lack chafe protection and support. Ditto some electrical. Not familiar with type of heater, so can't comment further, and always hard to get perspective from a photo.

BTW, I am going to be in Santa Cruz most of the first week of next month.

The wiring, the hose runs, the clamps, no hose on the drain valve, perhaps the lack of a check valve, it looks like there was or is leak, etc. Wh, what do you think is wrong with it?

Capt.Bill11 said:

The wiring, the hose runs, the clamps, no hose on the drain valve, perhaps the lack of a check valve, it looks like there was or is leak, etc. Wh, what do you think is wrong with it?

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What he said but what about the pressure relief valve that drains up?

All of the above, plus.

Isn't the pressure relief valve supposed to be on the hot side? Looks like its hooked up backwards.

Also, the tank is failing, check the leak?

Agree with Xsbank. I believe the pressure relief valve should be in the hot side.

Xsbank said:

All of the above, plus.

Isn't the pressure relief valve supposed to be on the hot side? Looks like its hooked up backwards.

Also, the tank is failing, check the leak?

Click to expand...

The location of the pressure relief valve is correct. It is coming out of the tank where it is supposed to.

The hose run from it is odd. But would work.

Greetings,
I thought the same thing about the drainage and location of the PRV but I checked the Seaward site and there is an in fitting and an out fitting AND the PRV fitting.

It's a faux hot-water heater that is actually a safe for storing valuables aboard.

Ok, all good feedback. I guess there is nothing really wrong with the water heater, but it is installed using practices I try and avoid in dirt homes. Finding balance as to what to modify is my goal (and fix the very slow leak it has.)

The T&P is in the correct place.
The T&P valve should technically flow down to where it can drain, but it actually goes up to a though hull above the water line. I think I will drill a 1/4" hole down low in the tubing to allow it to empty out of the 'trap' into the bilge. If it ever 'goes off' from temperature or massive pressure, most of the water will still go overboard, but the drain itself will remain dry other wise.

The check valve is cocked 45 degrees and probably has not fuctioned since it was installed. I actually think I will remove it as it is not needed. It's also quite corroded even though you cant see it from the picture.

There is way too much plastic connected to the water heater. The drain valve is plastic and will be replaced with a full port brass ball valve with a hose thread adapter on it. These plastic valves, never seem to drain water heaters efficiently , and they have a nasy habit of not shutting off again after you open them once or twice after a long period of time. It's a breeze to flush a water heater with a ball valve installed on the drain.

The hot and cold supply at the water heater both use some sort of funky PVC compression fittings connected to PEX. PVC is usually not rated for hot water. The unit is leaking from these fittings. They will be replaced with brasss nipples and then run 6 inches or so away to brass unions with pex adapters, where they will be exposed to less heat. A ball valve on the cold side would be a good idea as well. PEX piping really loses its strength above 175 degrees. I have seen solar systems that have made pex piping look like candle wax. So the farther away the better.

The wiring is not so bad, but I'll tuck that hot wire back in carefully.

If I actually had to remove the water heater, I would just replace it with a new one, but for now, I'm going to just freshen up the previous owners install.

That is a good call about the double clamps on the engine coolant loop. I'm not sure there is room for them but ill do it if its possible. I'll probable add some valves on the supply and return side of that loop somewhere close to the engine room. No need to lose my engine because of a hot water heater failure down the road.

Thanks all for your input.

Scott

Scott, this is a timely post. I just replaced the water heater on my boat on Monday because of a failed relief valve. The tank was original and 15 years old so I figured I might as well replace the whole tank.

All, note I have NT 37-15, Scott has 37-14.

Mine came from Nordic with double hose clamps on the heat exchanger hoses. The heat exchanger connections are also on the back side (actually forward side...the side that faces the engine room). This makes for slightly shorter hose runs without the extra 180 degree bend.

The plastic drain valve is standard on the Seaward tanks. They recommend replacing the drain plug with a sacrificial zinc (actually it's something other than zinc...whatever you freshwater people use).

The check valve was installed correctly on my tank and in good operating condition. I didn't think about it enough to decide if it's necessary.

The T&P relief valve on my boat was plumbed to the same overboard vent as the fresh water tank vent. I knew I had a problem when the fresh water pump was cycling every 10 minutes or so, I had no obvious leaks in the system, and water was constantly dripping out of the fresh water tank vent. It took me some time to figure out what was causing this combination of symptoms since it wasn't clear where the T&P valve vented overboard.

My boat had the same type of PVC connections/tubing as yours. It has lasted fine for 15 years, so I figured it must not be too bad. No leaks on mine. I reused it as is.

Wiring on mine was neat from Nordic. You can open up the cover and tuck that wire back in. Just one screw at the top of the cover.

It looks to me like the PO replaced the tank and didn't do as good a job as the Nordic factory. The piping and wiring on mine was quite a bit cleaner.

You obviously have much more knowledge in this area than I do, so I'll be curious to see the "after" pictures and description.

bligh said:

I'll probable add some valves on the supply and return side of that loop somewhere close to the engine room. No need to lose my engine because of a hot water heater failure down the road.

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If nothing else, this is what I would do first as well ...

If you remove the check valve your hot and cold water could mix.

I think it was touched on above, but that wiring makes me nervous. Looks like solid copper Romex for house use, unsupported with no protective sheathing or strain relief.

You can get away with well supported Romex in a boat. Hanging loose and draped over other things, not so much.

All in all it is a pretty rough looking installation. Was it done during the initial build or did an errant owner do it a few years later?

sunchaser said:

All in all it is a pretty rough looking installation. Was it done during the initial build or did an errant owner do it a few years later?

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The latter. But i doubt its much different than the original install.

Ok I see what you did there, the photo makes it look as if the cold intake goes to the Pressure relief valve but it's an illusion, the cold intake is just slightly below and to the left.

You can eliminate the valves if you use a heat exchanger on the engine, then a failure of the coil in the water tank will not put glycol in your hot water, nor will it cause the engine to fail. Valves would require you to spot the failure in a timely manner but an exchanger will not. Valves just make it easier to isolate the heater, should you need to.

Definitely a dog's breakfast.

My install is very similar. My port engine is connected to the water heater and is used as a heat exchanger, like in the picture. I had not thought of a internal failure of the heat exchanger plumbing dumping engine coolant into the water heater and thus disabling the port engine.

So Xsbank, are you suggesting installing 2 ball valves on the hoses from the engine to the water heater, one on the inlet and one on the outlet?

i am not sure that having failure of the exchanger will disable the engine. Now i suppose it could water down the antifreeze enough to allow it to freeze, which would be bad. i am not sure the engine cares if it is drinking from a big tank of liquid.

It will contaminate your fresh water system with antifreeze...which in small concentrations you may not notice but could still lead to glycol poisoning.

timjet said:

So Xsbank, are you suggesting installing 2 ball valves on the hoses from the engine to the water heater, one on the inlet and one on the outlet?

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Valves at the engine take offs are pretty common if not normal in my experience.

My Take

First, regarding the fittings. They appear to be Whale brand. This is a VERY common fitting on boats. Whale fittings are sold everywhere marine plumbing is sold.

Second, the wire. The wire could be solid core as mentioned, but it could just as easily be marine two strand wire from the photo. Cant see it from the photo but I'm assuming there's strain relief on the wire inlet.

The pressure valve should go down. Into the bilge is fine, its an emergency only system.

Aside from being a sorta sloppy installation, There is nothing else technically wrong I believe.

There is supposed to be a hose on the pressure relief valve leading to the bilge as per ABYC (makes sense if you think about it ). I believe there should be a hose on the drain tap for the same reasons.

Double clamping is not required and is ill advised as the nipples on these water heaters are too short to support a second clamp. A second clamp would just pull the hose off.

There is no air space under the tank. The insulation is fiberglass batting which soaks up any drips, leaks etc. and corrodes the aluminum tank inside the box. This is the major cause of short water heater life.

eseyoung said:

i am not sure that having failure of the exchanger will disable the engine. Now i suppose it could water down the antifreeze enough to allow it to freeze, which would be bad. i am not sure the engine cares if it is drinking from a big tank of liquid.

It will contaminate your fresh water system with antifreeze...which in small concentrations you may not notice but could still lead to glycol poisoning.

Click to expand...

I have to agree. An internal leak in the water heater coolant loop would be opposing the internal water pressure of the fresh water system. If the engine is at operating temperature, say 180°, the internal coolant pressure will still be relatively low, perhaps even lower than the fresh water pressure. If a hot water tap is full open, I suppose it could draw coolant into the system, but I don't think it would be significant enough to disable the engine. Any leakage would be dangerous for humans though.

Now, if the coolant leak is outside the water heater, the only thing that will save you is cut-off valves on both the inlet and outlet lines from the engine.

Maybe this is another reason to perform a periodic pressure test on the coolant side of the engine. The radiator-cap style of testers are inexpensive and easy to use. Test once with the cut-off valves closed to check the engine side. If OK, then test again with the cut-off valves open, the water pressure pump off and a hot water faucet open. That should let you know if there is an internal leak.

Just thinkin'

Larry
M/V Boomarang

Xsbank said:

You can eliminate the valves if you use a heat exchanger on the engine, then a failure of the coil in the water tank will not put glycol in your hot water, nor will it cause the engine to fail. Valves would require you to spot the failure in a timely manner but an exchanger will not. Valves just make it easier to isolate the heater, should you need to.

Definitely a dog's breakfast.

Click to expand...

Well, yes. And no.

A additional heat exchanger is another potential point of failure as well, isn't it?

And whats a dogs breakfast?

ksanders said:

My Take

First, regarding the fittings. They appear to be Whale brand. This is a VERY common fitting on boats. Whale fittings are sold everywhere marine plumbing is sold.

Click to expand...

Whale brand or not, the fittings dont meet my standard and IMO dont belong in an environmentally harsh area (near the hot water heater).

boatpoker said:

There is supposed to be a hose on the pressure relief valve leading to the bilge as per ABYC (makes sense if you think about it ). I believe there should be a hose on the drain tap for the same reasons.

Double clamping is not required and is ill advised as the nipples on these water heaters are too short to support a second clamp. A second clamp would just pull the hose off.

There is no air space under the tank. The insulation is fiberglass batting which soaks up any drips, leaks etc. and corrodes the aluminum tank inside the box. This is the major cause of short water heater life.

Click to expand...

Thanks for the tip on the hose clamps.

The T&P currently goes overboard. Isn't that better than in the bilge?

Air space under the tank. Are you saying I should shim up the tank a bit? OR is there space between the outer housing and the tank in which insulation is sandwiched? The insulation is a bit wet at the moment since the 'whale' fittings are leaking.

LarryM said:

I have to agree. An internal leak in the water heater coolant loop would be opposing the internal water pressure of the fresh water system. If the engine is at operating temperature, say 180°, the internal coolant pressure will still be relatively low, perhaps even lower than the fresh water pressure. If a hot water tap is full open, I suppose it could draw coolant into the system, but I don't think it would be significant enough to disable the engine. Any leakage would be dangerous for humans though.

Now, if the coolant leak is outside the water heater, the only thing that will save you is cut-off valves on both the inlet and outlet lines from the engine.

Maybe this is another reason to perform a periodic pressure test on the coolant side of the engine. The radiator-cap style of testers are inexpensive and easy to use. Test once with the cut-off valves closed to check the engine side. If OK, then test again with the cut-off valves open, the water pressure pump off and a hot water faucet open. That should let you know if there is an internal leak.

Just thinkin'

Larry
M/V Boomarang

Click to expand...

Interesting, Larry. Ok so that begs the question as to what pressure the radiator cap will allow pressure to pass through. If the HX fails in the water heater, the fresh water pump could conceivably pump water from the storage tank out through the cap on the coolant reservoir couldn't it? What pressure does an average water pump achieve?