Tankless Propane Water Heater ?

[boatpoker]

Originally Posted by tdunlap

In ABYC case, there work is not mandated by anyone. They are recommendations. They would have no teeth at all, if it were not for insurance companies choosing to use some of it. I have had surveyors tell me I needed things to comply, and the insurance company stood by their word, even when they were wrong. Battery boxes come to mind. They are not required, there are requirements for battery installation, but boxes are not one. Of course, how would you know, if you don't want to shell out the money to buy the "recommendations". I'm sure your insurance company did bother to buy them; they just rely on the surveyor.

Tim

You are correct, the Standard does not say "boxes", It says "Provision shall be made to contain incidental spillage and leakage of electrolyte". Having seen electrolyte eat a hole in the bottom of a boat I think I'll go along with ABYC on this one.

If you can do it without a box, more power to you.

[charlie p]

Here is what the L5 has in terms of sensors. This is based on actually inspecting the unit, rather than relying on the documentation or just speculating.

1. Water flow sensor. It is connected to a microswitch and prevents the unit from firing unless there is sufficient water flow. If the unit is running and the flow drops, it will shut down.

2. Water overtemp sensor. Located on the hot water pipe near the outlet, it will shut down the unit if the outgoing water temp is too high. The water must get pretty hot for it to kick in, but it does work. I know this from actual experience.

3. Flame sensor. A thermocouple located in the flame. This allows the unit to detect ignition and to shut down if the flame goes out.

4. Heat sensor. A thermocouple located high in the heat exchanger. It detects if the unit is actually heating up. It is unclear exactly how this is used but it is another sensor that can help detect improper operation. It is also unclear if this is used for overtemp detection.

The software also implements a 20 minute timer, which shuts down the L5 if it has been running for 20 minutes. This is a safety feature in case someone leaves the unit on and just walks away.

It would be nice if Eccotemp documented the units behavior more precisely, but for a $120 consumer product, it is not likely. Still, given the price, the set of sensors and the control system is pretty good. It is better than the $1000 Bosch unit I replaced.

Hope this clears up any misunderstandings of what is actually in the L5. And no, I have no connection to the company.

[Celestialsailor]

Thanks for that Charlie...If it does have a thermalcouple as stated in #3, it sure lets a lot of gas flow before it shuts it down. I have had it blow out due to too much wind over the poorly designed stack that was on my boat prior and reignite and a mini-explosion occurred. Nothing catastrophic but a few flames shooting out the side of it and I'm sure out of the stack too.
Like I originally stated...I have one and enjoy what it can do for the $100 I spent on it...but I watch it like a hawk.

[tdunlap]

Sorry, one last post. If you want a "cheap" tankless heater, the L5 would not be my pick.

This might be one that could be modified to work on a boat -
I can't believe they can make this for a $150

excelonlinestore.com/servlet/the-849/1.6-gpm-Excel-LPG/Detail

There web sites has much better informations, and details the heaters safety features. It even has an O2 sensor, so they say.

I have seen some people posting they have made vents to attached to these, sometime using the one from the heater they are replacing.

Just saying, and trying to bring the discussion back to useful for anyone who wants a low cost option. Still not ABYC, but none are without some modifications.