Water heaters

[Goldenstar38]

It's time to replace my water heater and in looking at what's available, I see units from Whale, Kuuma and West Marine, but they all seem to be virtually identical. Is this because they are the same units, or just the result of design limitations?

Looking at the lower cost units at this time only, up to say $350.00. Thank you.

 

[Capecodder]

Check with HopCarr or Defender for options, with shipping could save a few $$$

 

[Ken E.]

You might check out Torrid. I don't recall the price tag but the 20 gallon tank I installed a few years ago has functioned well.

 

[JohnP]

You might check out Torrid. I don't recall the price tag but the 20 gallon tank I installed a few years ago has functioned well.

Agree--Torrid is great installed a 10 gallon horizontal and it has met all our needs. Glass lined tank similar to old school Raritans.

 

[scott2640]

Is a tankless water heater even a possibility for marine use?

 

[TG]

I went with the Torrid 20 gal. Torrid is a bit pricey depending on the options and volume.

 

[BruceK]

Is a tankless water heater even a possibility for marine use?

I may have seen a propane one while viewing boat porn.

 

[Ken E.]

Torrids can be ordered with two heat exchangers. I use one connected to an engine and the other to the hydronic heat system.

 

[Bay Pelican]

A good way to start this search is to look at what you currently have. A new unit that can be installed without any significant changes is a bonus.

Another item to consider is your use of the boat. If you hop from marina to marina and basically exist on shore power than the wattage of your unit does not matter. If you live at anchor you have to determine whether you are better off with a 750 watt unit or a 1,500 watt unit. Assume the 750 watt unit will take twice the time to heat but will cause less of a load on your generator. My current six gallon unit using 750 watts requires 30 minutes to heat fully, whereas my old 1,500 watt six gallon unit required only 15 minutes to heat fully. Downside of the 1,500 watt unit was that the increased draw on the generator was such that I had to turn off one of my chargers while the water heater was heating, thus increasing overall generator run time.

If you move the boat frequently then a water heater with a heat exchanger that can be connected to the cooling system of your main engine is a bonus and should be considered.

Size of water heater is a debatable issue. Some believe in small units, that take up little space and can be heated quickly. These units are frequently very well insulated so that hot water can last for 24 hours or more. Larger units take up more space and take longer to heat. However, a larger unit allows for long residential type showers, washing machines and dishwashers.

There are several good brands. If your boat currently has one of these brands a replacement with the same model/brand might be easier and worthwhile.

 

[koliver]

Is a tankless water heater even a possibility for marine use?

If you are concerned about what your insurer will approve, a tankless may not be in your future. The only one I have seen is on a boat owned by a guy who doesn't care about the insurance, ie is self insured for any loss due to the unprotected propane appliance.

+1 for Torrid

 

[Shoalwaters]

There are electric tankless water heaters. Would like to hear more.

 

[psneeld]

I bought an Isotherm 8 gal water heater to replace my Kuma square, SS, glass wool insulated water heater.

Night and day.

I never run out of hot water for 2 living aboard. 2 showers, followed by breakfast dishes get done. Of course if both showers are longer than average....who knows. The element is only 750 watts, but the tank insulation is so good, it seems that even 8 gallons heats faster than 6 in the old design, square, poorly insulated ones.

I have had the heater off for 2 days, unused, and the water us still warm enough to shower with for at least 1 person.

I have yet to see a practical solution for electric on demand water for the boat. To much juice for the average smaller vessel and would require the genset running whenever you needed it.

 

[Bay Pelican]

An electric tankless water heater requires substantial power. I have a home unit for an outlying bathroom sink. The single faucet unit requires a 60 amp 220 volt circuit breaker. I assume that make units which require less power but still on a boat it would consume near the maximum available on the boat.

 

[Portage_Bay]

If you have hydronic heating you can install an Everhot Tankless On Demand Copper Water Heater.

 

[Xsbank]

Pelican's advice to replace the one you've got with another (if it gave satisfactory service) is a good one as the plumbing will fit. Mine will be changed soon too and I have chosen another, larger Torrid but the installation will be difficult as it's fittings will all have to be relocated.

When you decide, don't forget to buy all the fittings and plumbing doodads too.

 

[CPseudonym]

On demand water heaters on boats our size is a false economy. Even the small units need a minimum of 30 amps. Get a standard storage tank, there's a reason why everyone else uses one.

 

[Rebel112r]

Mr Ken E. I have been considering a 2 exchanger torrid, how long to heat the water using only the hydronic? The Torrid would be the 15 or so gallon.. Thks

 

[Ken E.]

"Mr Ken E. I have been considering a 2 exchanger torrid, how long to heat the water using only the hydronic? The Torrid would be the 15 or so gallon.. "

On the heat exchanger connected to the hydronic, I don't know how long it takes for the water to come up to temperature from it - I've never used it in that manner. My usage is more like using the tank as a transfer medium....in other words, if the tank is being heated by the engine, that heat can be shared with the hydronic, or visa versa. Same thing if the water is being heated electrically by genset or shorepower, the heat can be shared with the hydronic. I do know that from the engine exchanger, the tank comes up to temp very quickly, I'd say 20 minutes or so at the most.

 

[rhakct]

replaced my 30 year old Raritan? with the 6 gal. Kuuma last year, so far pretty happy - did take a few trips to the big box store for plumbing stuff but I figured on that going in - at my age now a heater that might last another 30 years doesn't have the appeal it did when I was 40ish...

 

[Lou_tribal]

Just for 2 cents I will say that fit the less expensive biggest one you can fit connected to your engine cooling circuit. Whatever its price one day it will fail, up to you to evaluate if price difference worth it. Wrap it in insulation blanket to get a better temp conservation. Using engine heat it is getting so hot that you just use few hot water. I have a 6 galllon one it is enough for a daily shower for 2, dishes cleaning and toilet in the morning.
Of course it depends on ur usage. Do you plan to use it most of the time in your marina connected to the dock? Do you plan to use it mostly at the anchor? How many days do you expect to stay without running? All these will drive your choice.
I plan to replace mine with a 12 gallon for longer capacity as mine is in its end of life.

 

[HopCar]

I like to avoid water heaters with aluminum tanks which most of the cheap ones have. I once cut open an aluminum water tank and the jelly like slime that was in there was disgusting.

My favorite water heater is the Isotherm Spa series. Stainless tank, 750 watt element, heat exchanger and a mixing valve.

The mixing valve is nice in that it lets you heat the water much higher than is safe but it mixes cold with the hot as it comes out of the tank bringing it down to a safe temperature. That way you get a lot of usable hot water from a small tank.

The Spa series of water heaters is not cheap, it falls kind of in the middle price wise.

I may be biased as I sell these but I sell these because I really think they are a good value for my customers.

 

[psneeld]

I like to avoid water heaters with aluminum tanks which most of the cheap ones have. I once cut open an aluminum water tank and the jelly like slime that was in there was disgusting.

My favorite water heater is the Isotherm Spa series. Stainless tank, 750 watt element, heat exchanger and a mixing valve.

The mixing valve is nice in that it lets you heat the water much higher than is safe but it mixes cold with the hot as it comes out of the tank bringing it down to a safe temperature. That way you get a lot of usable hot water from a small tank.

The Spa series of water heaters is not cheap, it falls kind of in the middle price wise.

I may be biased as I sell these but I sell these because I really think they are a good value for my customers.

 

[ranger58sb]

I like to avoid water heaters with aluminum tanks which most of the cheap ones have. I once cut open an aluminum water tank and the jelly like slime that was in there was disgusting.

My favorite water heater is the Isotherm Spa series. Stainless tank, 750 watt element, heat exchanger and a mixing valve.

The mixing valve is nice in that it lets you heat the water much higher than is safe but it mixes cold with the hot as it comes out of the tank bringing it down to a safe temperature. That way you get a lot of usable hot water from a small tank.

The slime comment is concerning; I haven't noticed anything like that, at least from normal use... What would cause it? Why associated with aluminum?

Can a mixing valve like that be added to most water heaters? Ours is an Atwood, nominally 11 gal aluminum alloy tank (10.5 actual), and we've never run out of available hot water... but the mixing valve idea sounds interesting.

-Chris

 

[mbevins]

The slime comment is concerning; I haven't noticed anything like that, at least from normal use... What would cause it? Why associated with aluminum?

Can a mixing valve like that be added to most water heaters? Ours is an Atwood, nominally 11 gal aluminum alloy tank (10.5 actual), and we've never run out of available hot water... but the mixing valve idea sounds interesting.

-Chris

This is actually a good idea. I've got water temp set very high so as to get more water from my small tank. I have to remember to warn guests.

Don't see why you couldn't make one up. eBay sells them for showers . Usually a closeout sale of someone s mismatch inventory. No one says it has to be connected to the shower stall.

 

[Ken E.]

A mixing valve should be standard fare when the tank is engine heated - 160+ degrees engine temp is scalding to the skin. The valve I have wasn't cheap at north of $100, but as said by an earlier poster, a serviceable valve could be made from off the shelf parts.

 

[sunchaser]

I like to avoid water heaters with aluminum tanks which most of the cheap ones have. I once cut open an aluminum water tank and the jelly like slime that was in there was disgusting.

100% correct. My prematurely failed Seaward comes to mind. Buying cheap usually means AL,

 

[Bay Pelican]

Seem to recall my new (last year) water heater a 6 gallon Isotherm Spa was in the $300 US range. Outside was plastic, but not the actual tank. Came with a mixing valve and great insulation.

Hadn't given any thought to search for a less expensive unit.

 

[chc]

Replaced our 6 gal Kouma water heater w/ an Isotherm Spa 5.3 gal unit. No difference in apparent capacity, as mixing valve stretches hot water use out. Big advantage to us is that I can use our Honda generator to drive the 750 watt element after several days of no engine use at anchor. It would not push the 1500 watt element in the other heater. Also gained an amazing amount of space in the compartment.

 

[cappy208]

I had to replace mine last year. HopCar gave me an EXCELLENT price.

I was trying to figure out internet prices, shipping, costs of buying a 'cheap' model, then adding: stainless hoses, an actual Thermactic tempering valve, and the anode. Guess which brand comes with all standard? Isotherm! It was actually more affordable to buy the isotherm from HopCar ready out of the box, than part it out and try to 'cheap' it.

I fit an 8 gallon in the place my old 6 gallon was. 750 watts, more tempered water for showers, win win. Isotherm.

Thanks HopCar again for your terrific product, price and hospitality.

 

[HopCar]

Capps, thanks for the kind words. Glad it all worked out.