My hotwater heater

South of Heaven · Posted: Sun Oct 30, 2016 7:21 pm Post subject: My hotwater heater

I've noticed that my hot water heater sometimes makes the reverse polarity light come on when on shore power but it still heats and works fine.....AND doesn't affect the other shore power connections (fridge, outlets, battery charger etc).

BUT today when I used my Honda EU2000i and connected my shore power to it, I noticed the generator really "surged" and "sounded weird" when I turned on the hot water heater from the electrical panel. As soon as I heard the genny "surging" I turned off the hot water heater.

What's the deal?? Do those heaters require a significantly higher amount of juice? Or is there something going on with my system? Buss system?

journey on · Posted: Sun Oct 30, 2016 8:17 pm Post subject:

Well, the hot water heater isn't the most complex instrument, just a restive element across the line. I'd check the wiring to the hot water heater. Specifically the ground. And you might make sure that the heater has the correct polarity if it's been doing it for a long time. Check for loose connections as well.

If you've used the Honda before i assume it hasn't offered up those symptoms. The 1500 watts of the heater is right at the top of the Honda's capability which, I believe is 1600 watts. If anything else was running, might have pushed it up to the limit. But still check the wiring.

If the wiring checks out OK, you can get a new heater element from Defender. Just a thought. Usually heaters work or not. They're really simple.

Boris

South of Heaven · Posted: Sun Oct 30, 2016 8:43 pm Post subject:

South of Heaven · Posted: Sun Oct 30, 2016 8:43 pm Post subject:

thataway · Posted: Sun Oct 30, 2016 10:47 pm Post subject:

Some water heaters are 1200 watts, some 1500 watts--either way, that is a bunch of power--and as Boris says, close to the max output of the EU 2000. Depends on what else you have one--the battery charger could put it over the limit.

The Honda will often cause the reverse polarity light to flicker on, since it has a "floating ground".

Avidmagnum12 · Posted: Mon Oct 31, 2016 7:58 am Post subject:

The Honda EU2000 is a great unit but has its limits. As Bob and Boris pointed out. I run everything but the hot water heater at one time. For me that's the charger, refrigerator, 5000 BTU AC and a computer. I don't have a microwave. When I want hot water I turn the everything off and flip the switch for the water heater. Yep if you have it on the idle setting it spins up. You'll know when the water is hot....the Honda gets quiet in 30 to 40 minutes or so. Just flip off the heater breaker and flip on the others. We may do this once or twice a day.or not at all if we are in water conservation mode. My wife can easily make 24 gallons last a week or more if fresh water is hard to get. Tom

Jake · Joined: 31 Jan 2012 Posts: 171

Sorry this is a little off topic but questioned came to me. I don't have a boat with shore power so please understand. If you are running the water heater off of the generator, any reason you can't run all your DC "stuff" at the same time?

Thanks
Jake

South of Heaven · Posted: Mon Oct 31, 2016 9:25 am Post subject:

South of Heaven · Posted: Mon Oct 31, 2016 9:28 am Post subject:

thataway · Posted: Mon Oct 31, 2016 10:55 am Post subject:

texasair · Posted: Mon Oct 31, 2016 11:30 am Post subject:

Most heating elements are available in a wide power range and it is pretty easy to change them out. You could drop down to a 1000w element and your EU 2000 will purr like a kitten. The water would still get just as hot, it would just take longer.

journey on · Posted: Mon Oct 31, 2016 11:30 am Post subject:

I changed the heating element in the water heater to a 240 VDC element. At 120 VDC, this draws ~400 watts, well within the capability of a Honda 1000. But, it takes 4 times as long to heat up. Costing $27, it was cheaper than a new Honda 2000.

Defender has them , Model No. 74032 = 240 Volts AC, $26.95. Works great. Defender also has sacrificial anodes for Seaward heaters, Model No.
74556, $23. Ever replaced yours? I've replaced the complete heater (on another boat) when it rotted out, so the anode is cheaper.

Judy can only get 5 days out of the 23 gal water tank on the 25. I'll speak to her about that.

Boris

JamesTXSD · Posted: Mon Oct 31, 2016 1:22 pm Post subject:

Your Honda 2000i generator will generally run in "eco-mode" - only spooling up when there is more of a current draw. Your water heater is a big current draw, thus the reason the generator gets louder. We have found with 30 amp, we try to generally run one major draw at a time... your Honda generator is rated at 18 amps; you are pretty much going to be limited to one major draw at a time. Things like a microwave, hair dryer, and coffee maker will likely draw less than the water heater.

Getting the reverse polarity is normal when using the generator - it is a function of the ground, and won't cause your electronics a problem.

Nice to have the available power and the amenities - a 25 equipped with a Honda (or similar) generator is a great way to go. If we were going to be where fresh water wasn't easily available (as in cruising in some parts of Canada), we could make the fresh water go a long ways, usually 5 days or so. And carried a couple of 5 gallon containers as back-up. You can get very conservative by using dish water to flush the toilet. Quick rinse in the shower, water off, soap up everything that needs soaping up, then another quick rinse. The sprayer that comes standard in the 25 encourages conservation. Don't let water run while you wait for the hot water to get through the lines. I would shave in a cup of water; figured 1 to 2 gallons at most to shower, usually less. Solar showers where it would work, and you can run the line in through the head window if you need the privacy.

Cruising in a small boat isn't always about the luxury, but about being as comfortable as the situation allows. And sometimes that means not running the generator (thus, the solar shower).

ssobol · Posted: Mon Oct 31, 2016 1:42 pm Post subject:

There are adapters available (search online) that solve the reverse polarity issue when using portable generators in situations like our boats. I believe that this is caused by not having a good earth ground. It doesn't happen in all boats.

In my boat, a reverse polarity detection will cause the external power to shut off. I haven't had issues with reverse polarity from my Honda generator. I sometimes get one when using external AC and the cabin door slams shut. Time for a Smart Plug I think.

Kushtaka · Posted: Mon Oct 31, 2016 1:59 pm Post subject: