On Demand Propane Water Heater?

Ross · Oct 29, 2010

Stephen, If you educate yourself in the details of gas plumbing and if you follow your new education as though your life depended upon getting everything right, then you will probably never have a problem. I can't begin to count the people I have encountered that simply don't have a clue about product safety. I still meet people that can green beans in a boiling water bath. They think the botulinum is just a fancy name for Botox. I saw an online recipe for canned pumpkin bread that has been proven to be an unsafe method of canning.
There is much published on line that is either cute and not based on knowledge or it is published by someone who doesn't comprehend well that which he reads. Be careful and knowledgeable, that is what Mainesail does and is and what he is trying to get the rest of us to follow.
History is written in the blood spilled by the mistakes of others. We have been told that experience is the best teacher but learning from the experience of others is the least painful way of learning.

Seattle Scott · Nov 1, 2010

Couldn't get the CO detector to go off

Ran the heater on high flame for 5 minute in the cockpit locker with the CO detector in the locker - it didn't go off. Bought another detector and repeated the test - same result. Both detectors appeared to be functioning using the self test feature on both.

Edited to add: So I might as well mount the second detector in the air space the heater exhausts in.

Ross · Nov 1, 2010

Re: Couldn't get the CO detector to go off

Most of my life has been lived in homes with either propane or natural gas water heaters and cooking stoves. The only people that i have known personally to be poisoned by CO were in a house heated by coal.

John Nantz · Nov 1, 2010

Joint Leaks

Stephen Trapani said:
The advantage of having remote hot water on my boat would be huge. South Puget Sound is filled with numerous wonderful gunkholes perfect for remote anchoring. My raw water 2QM15 won't do it. I know of no other option for comfortable living for the less hardy members of my crew. I could give up that dream. If there is no reasonably safe way to do it, I will. But it has to be based upon the truth. And so far, based upon my best, yet fallible means of discerning the truth, what I see is a safe way to use the Excel heater to achieve this dream. A CO detector, propane detector, liberally used solenoid switch, my nose stuck into compartments before ignition and regular inspections seems like they should more than enough to make this dream a reasonably safe reality.

I'm still open to hearing where I may be going wrong and I truly appreciate all the input and concern so far. Thank you.

In previous posts there was a mention of joint leaks.

Several years ago there was a requirement to have USTs installed in a certain maner and be tested for leaks. Basically, the owner had to prove that USTs (Underground Storage Tanks) didn't leak. Virtually everyone who owned or operated a UST fully believed their tank didn't leak.

Well, as it turned out, probably 98% of all USTs DID leak. Maybe not at the tank but at the fittings. One could run tests and each of the pipe fittings and somewhere between the tank and the end of the line, often a gasoline pump, there would be a leak, and sometimes a huge one.

Okay, so this is for gas and diesel and we're talking LP. If you're in Olympia and you want to check what I say just talk to the Ecology people there, and especially the UST folks, and see what they say.

If it were me and I wanted hot running water I'd check out something like an Espar diesel heater. They don't take up much room, in fact, they're really tiny, and won't have the worry that LP would have. Boat Electric on Westlake, Lake Union sells them. And I believe there are other brands available.

I can certainly relate to you wanting hot water on demand in Puget Sound. I'd like it too, but I don't want to have to worry, either.

Douglast · Nov 8, 2010

with any instant heater..or heat exchanger...always when plumbing it in have shut off valves on each side of the exchanger..and just after the shut off on the feed and just before the shut off on the discharge mount boiler drains...that way you can shut off the valves and hook up a pony pump and pump a descale solution from a bucket supplying from one boiler drain and the other boiler drains through a hose draining into the same descale bucket...and you can reverse it..and that keeps your instant demand heater in great shape because they can plug up very easily an these valves and boiler drains with the hose bibs mounted ahead of time make any issues minor..

mitchf · May 3, 2011

excel hot water

so glad to read your post. I want to do the same but do not have propane yet. do you imagine that I could do safely by keeping propane tank outside and use just when showering on a hook and then disconnect? I don't see how I could start making a proper propane locker.

Thanks

JoeD said:
This is the one I have. Found it because back in 2006 on this site several peo[ple were talking about it. Let me see if i can find it. But here is the link.

Excel http://www.excelamerica.com/calentadores_eng.htm.

It cost about $250.00 with freight. many are used on boats. I found out about them from another Forum.

This of from Sailboat Owners Jim 04-11-2006 04:05 pm

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Buy a Ventless Propane Water Heater

I installed an "Excel" ventless, pilotless propane water heater on my 450 about 2 years back and it's hands down the best modification I've made. I bought it from a distributor on EBay for around $150 and plummed it into the hot water lines just after they exit my electric heater. When the hot water in the tank runs out I turn a lever that directs the outflow from the tank through the heater and back into the hot water circuit. I installed the heating unit on the bulkhead under my companionway. I run it at less than 1/2 its maximum so I don't burn myself in the shower. It operates at a claimed efficiency of around 80%. I put a splitter on my propane line inside the propane box after the stove solenoid so the propane circuit for the heater is as safe as the one for the stove. Engine-based hot water systems are great when the engine has just been running and electric is great when you are connected to shore power. I spend a lot of time under water away from the dock and my friends and I ALL want hot showers when we get back to the boat. No one wants to run the engine or the generator for an hour to refill the tank before showering. Jim. "

Have looked at two fo them installed on other boats. They work well. The ease of installation and the price is what sold me.

Steve W · May 3, 2011

I've heard nothing but fantastic things about the Excel unit. I know two sailors who've installed them (in aft cockpit lockers), one 'vented' overboard, the other in the closed locker. The unit is advertised as "ventless" but I guess it would be your choice whether or not to vent. The biggest issue I've heard is that the exhaust vent at the top of the unit gets really hot after a while.

But as someone on this thread put it, how long are you really running hot water? I don't know the specifics about the girl who died from CM poisoning but I can't see running the hot water for more than 4-5 minutes for an on-board shower. And even doing the dishes you're just not running the thing for all that long.

That heater is my next 'round-2-it' project. Probably next winter after layup...

Maine Sail · May 4, 2011

windsock1 said:
I've heard nothing but fantastic things about the Excel unit. I know two sailors who've installed them (in aft cockpit lockers), one 'vented' overboard, the other in the closed locker. The unit is advertised as "ventless" but I guess it would be your choice whether or not to vent. The biggest issue I've heard is that the exhaust vent at the top of the unit gets really hot after a while.

But as someone on this thread put it, how long are you really running hot water? I don't know the specifics about the girl who died from CM poisoning but I can't see running the hot water for more than 4-5 minutes for an on-board shower. And even doing the dishes you're just not running the thing for all that long.

That heater is my next 'round-2-it' project. Probably next winter after layup...

Be sure to read the entire thread. These units still do not meet current US marine safety standards and owners are being forced to remove them when insurance survey time comes. Can they work? Sure. But you should to balance that with applicable US safety standards and what your insurance company will allow.

EDIT : 8/11/2012 - I just had to uninstall/remove my first ventless, on-demand water heater per an insurance survey!! Owner is IRATE that the company Excel LIED TO HIM!!

The best approach is to call your insurance company before hand and ask if a non-vented LPG appliance that does not meet ABYC or ANSI standards is okay to install on your boat and still retain coverage..

Bill Roosa · May 4, 2011

CO is only part of the problem with having a flamable gas plumbed into the cabin. if the thing malfunctions and vents gas you are in for some overly exciting events when the non-explosion proof bilge pump kicks in.
There are really good reasons that these things need to be installed correctly and to the safety standards (note those two things are not the same thing in most cases!!!)

alexco38 · May 4, 2011

There are 3 options:

(1) IMHO if you have an inboard engine use a ABYC approved fixed mount unit. Running the engine for 10-15 minutes will get 6 gal of hot water. At the slip, just plug in the shore power.

(2) Solar shower, basically a black plastic bag hanging outside for a while will be the cheapest.

(3) But if you absolutely need hot water and don't have any means to generate heat, like an outboard motor, use a Coleman portable water heater:

http://www.coleman.com/coleman/colemancom/detail.asp?product_id=2300B700

It is much safer as you place it on deck. There is an optional shower attachment.

alexco38 · May 4, 2011

The real issue here is insurance. If you blew up the boat and your neighbors and the insurance found that you have an un-approved water heater on board, they may not have to pay.

Saving $100 one time may not be all that good an idea.

tommays · May 5, 2011

NO

The real issue is despite huge demand from the sail/powerboat industry nobody has been able to make a compliant device.

Maine Sail · May 5, 2011

tommays said:
NO

The real issue is despite huge demand from the sail/powerboat industry nobody has been able to make a compliant device.

Yes, this is the "real" issue for an unsuspecting boater who reads the misleading marketing from Excel, installs an un-vented heater, then a year later is forced by his/her insurance company to remove it for insurability.

We have all sorts of minimum standards to abide by every day. A good friend built a gorgeous Ipe deck on his new beach house and installed 1X19 stainless rigging as railings horizontally. He could not get a certificate of occupancy until the wires were vertical and not horizontal. The concern is that kids could climb them like a ladder and the fall off into the sand. All this despite the deck being a whopping 16" off the beach sand. The code/standard still required railings built to a certain height and with vertical stiles that had to be spaced correctly. No CO until you meet code..

Would his 16" high deck have been safe? Sure but he had to spend thousands more to rip it up to meet "standards". Could the Excel be safe? Sure but you may need to rip it out to pass an insurance survey.

As I have said MANY times in this thread CALL your insurance company and ask them if a heater that does not meet the minimum ANSI or ABYC standards is insurable.

tommays · May 5, 2011

With gasoline being the predominate power source in the boat industry you will find its the reason all your bilge pumps/battery switches and such are ignition protected and i suspect the reason the industry is staying away from the unit as water heaters tend to be installed in engine compartments and as such are for the most part ignition protected

jokers819 · Jun 13, 2011

Hot water on demand

Stephen Trapani said:
Hi,

I need a new water heater and instead of buying another cheap electric, which worked fine until it didn't, I would prefer something I can use without shore power. So far the best possibility I can come up with is an on demand propane like this one:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120314340969&ssPageName=STRK:MEWAX:IT

The problem with the on demand propanes is that they require venting, so a large chimney would ordinarily have to be cut. My idea to beat the system is to mount it on the aft railing. The problem is that the models like the one in the link can't handle much of a breeze before it puts it out and needs to be restarted. What has anyone done with these to make them work?

They have one in west marine that looks great about the size of a stereo I think its electric ,the only problem I see is that i dont carry generator on board so It can be used only dockside