Water Heater Question

[saopm]

My water heater stopped making hot water off of the engine. I assume there is a clog in the loop from the engine. Any advice on tracing out the problem? Is there a thermostat in the Water Heater that may need to be replaced? The unit was replaced 4 years ago.

 

[Brite Idea]

How important is hot water to you? The water heater is fine it is the POS 1/2 diameter tubing that is clogged and will corrode right to nothing if you don't bypass it ASAP! You can disconnect the hose at the heater or the engine it's your choice. When you disconnect the hose all you need to do is loop it from one fitting to the other. If you want hot water you need to replace the water heater every couple of years. Keep in mind that you have hot water when your plugged into dock side electric. Also there is no thermostat in the raw water loop.
Rob

 

[dan313]

On my boat the fittings for the water heater rotted out from the salt water from the engine and i had to replace the heater. When i installed the new heater i did not hook up the hoses from the engine. I placed a piece of pvc sprinker pipe between both hoses to complete the loop. If i want hot water i use the dock side power and only have fresh water in the tank.

 

[ZZ13]

On my other engine not connected to the HWH, there are just plugs in the holes. Why would you need to complete the external loop? Could you just put plugs in those two holes as well? What say ye, Lazy Daze?

 

[Jimmy Buoy]

You shouldn't have to plug the two fittings. Water from the heater should not be able to enter this engine coolant hose circuit.

 

[Gunn]

On my other engine not connected to the HWH, there are just plugs in the holes. Why would you need to complete the external loop? Could you just put plugs in those two holes as well? What say ye, Lazy Daze?

I assume you are talking about the engine fittings, you have plugs there. That is fine to do. Either way is fine. What I found when I accidentally broke one of the HWH fittings and had to close this loop also was that I couldn't get the barbed fitting off the engine to install a plug; there were too many other things in the way...So I too just closed the loop with a section of the hose going from outlet to inlet on the engine.

To the OP, when my fitting broke, I then tried to remove the hose from the other fitting on the HWH, which also promptly broke. And in both cases, the hose was completely plugged up. Not sure if it was sand, shells and other stuff or just corrosion creeping through the fitting to seal it.

I still have hot water when using the generator too. Heck, even my cold water supply is pretty hot after an hour or so cruise, so I still get engine heated hot water... :smt001

 

[JimG]

You can disconnect the hose at the heater or the engine it's your choice. When you disconnect the hose all you need to do is loop it from one fitting to the other.Rob

When i installed the new heater i did not hook up the hoses from the engine. I placed a piece of pvc sprinker pipe between both hoses to complete the loop.

On my other engine not connected to the HWH, there are just plugs in the holes. Why would you need to complete the external loop? Could you just put plugs in those two holes as well? What say ye, Lazy Daze?

If you don't want to use the heat exchanger in the HWH, take the hoses and fittings off the engine, and install two plugs in the block.

 

[saopm]

Thanks for the info guys. I tried forcing water through the loop with the garden hose. I got it to dribble a little but she does not want to clear out. I do like having the hot water especially when beached all day with the kids. Unfortunately it is a pain in the azz to replace the water heater on my boat. At least it works when plugged in.

 

[JimG]

Thanks for the info guys. I tried forcing water through the loop with the garden hose. I got it to dribble a little but she does not want to clear out. I do like having the hot water especially when beached all day with the kids. Unfortunately it is a pain in the azz to replace the water heater on my boat. At least it works when plugged in.

You might try pushing a straightened out coat hanger (or similar piece of wire) through there to un-plug it.

 

[Bucit]

Unfortunately it is a pain in the azz to replace the water heater on my boat. .

Yep, been there done that. Manifolds/risers need to come of, batteries moved and the trim pump moved out of the way. Then it's an act of god to get to the two screws in the back of the WH. Sore ribs for a week but I got hot water! :smt038

 

[saopm]

You might try pushing a straightened out coat hanger (or similar piece of wire) through there to un-plug it.

I'll try this next time I'm at the boat. I have a few HVAC duct zip ties which are long and somewhat rigid. I'll let you know.

 

[saopm]

Yep, been there done that. Manifolds/risers need to come of, batteries moved and the trim pump moved out of the way. Then it's an act of god to get to the two screws in the back of the WH. Sore ribs for a week but I got hot water! :smt038

I've already call my marina for a price quote. Although I do like to do things myself, this may be more then my faimly of herniated discs in my lower back can handle.

 

[Lazy Daze]

Standard garboard drain plugs will fill the holes in your engines. Remove the hoses an then unscrew the pipe-to-barb fittings and then install the drain plugs.

Were the hoses clogged up or is it the actual heater coil?

 

[Gunn]

Yep, been there done that. Manifolds/risers need to come of, batteries moved and the trim pump moved out of the way. Then it's an act of god to get to the two screws in the back of the WH. Sore ribs for a week but I got hot water! :smt038

From what I have heard and read, the trim pump needs moved and the batteries need removed from a 280DA. I have not heard of anyone (until now) mention that the manifold and riser (assuming only on port side of port engine) have to come off. I had planned on replacing mine this winter due to my heat exchanger broken fittings, but I really don't miss the hot water; the generator takes care of it if I need it.

 

[saopm]

Success!!! I pulled the hoses off the nipples on the heater. The clog was pretty much right at the opening on both the inlet and outlet. I poked at it for a few minutes with a flat head and shoved a 2 foot long HVAC wire tie through. Flushed with the garden hose and now I have full flow. The clog was mostly white scale type stuff. I assume corrosion from the copper in the loop. I’ll keep an eye on it, but overall the water heater seemed pretty solid from what I could see. Thanks again for everyone’s input.

 

[Bucit]

From what I have heard and read, the trim pump needs moved and the batteries need removed from a 280DA. I have not heard of anyone (until now) mention that the manifold and riser (assuming only on port side of port engine) have to come off. I had planned on replacing mine this winter due to my heat exchanger broken fittings, but I really don't miss the hot water; the generator takes care of it if I need it.

I did mine the same time I replaced the manifolds. You may be able to get the WH out without removing the port manifold but I can tell you from experiance that it was pretty darn difficult with it removed. Where there's a will there's a way I guess?

 

[JimG]

Success!!! I pulled the hoses off the nipples on the heater. The clog was pretty much right at the opening on both the inlet and outlet. I poked at it for a few minutes with a flat head and shoved a 2 foot long HVAC wire tie through. Flushed with the garden hose and now I have full flow. The clog was mostly white scale type stuff. I assume corrosion from the copper in the loop. I’ll keep an eye on it, but overall the water heater seemed pretty solid from what I could see. Thanks again for everyone’s input.

:thumbsup:

 

[rondds]

Had engine hot water on the previous boat. Do not on this boat. Don't miss it at all.

 

[Lazy Daze]

Good deal!

Now, the white scaly stuff sounds like salt. So the question would be, how much damage (if any) it did to the interior coil/loop. The coil is double walled, but whether or not you would notice salty "fresh" water before it sprung a leak (and your high water alarm went off) I can't say. Just make sure that you, at the very minimum, keep the proper tools and hardware on board to bypass the hot water while you're out on the water.

 

[Gunn]

Good deal!

Now, the white scaly stuff sounds like salt. So the question would be, how much damage (if any) it did to the interior coil/loop. The coil is double walled, but whether or not you would notice salty "fresh" water before it sprung a leak (and your high water alarm went off) I can't say. Just make sure that you, at the very minimum, keep the proper tools and hardware on board to bypass the hot water while you're out on the water.

Yes, I was going to say give the same advice (that I learned from you, Dennis)...because after I accidentally broke mine (while on the trailer) I was told how fortunate I was that -I- broke it, rather than it failing while underway in the water.