Setting up a propane system (stove on demand hot water)

[mrybas]

Hi,
I am adding a propane stove/oven and on-demand hot water heater.
There is a propane locker in the cockpit. The stove is in the galley, the hot water heater in an enclosed locker at the transom.
Can I add a T in the hose at the stove and run it to the hot water heater? Or will I need to run 2 separate lines from the tank?

[sy_gilana]

Dont be such a pussy, shower in cold water!

[Dsanduril]

Depends on whose rules you follow. If you follow ABYC then no joints allowed in fuel lines between propane locker and appliance, which means no tee to feed a second appliance (other than in the propane locker itself). There is an exception for a joint to transition between a hard pipe (say copper) and a flexible hose at an appliance that moves (gimballed stove). Otherwise ABYC says a single continuous run from propane locker to each appliance.

Other rule/standards systems may have different requirements.

[Cheechako]

No tubing joints inside any enclosed space. However, an on-demand in a closed space where you can't monitor it at all, is a huge risk anyway so it wont matter.

[deblen]

Helpful link
Safe Boat Propane System Installation

[mrybas]

Originally Posted by sy_gilana

Dont be such a pussy, shower in cold water!

Hahaha…funny coming from the guy in Panama/Columbia/San Andreas! You try that in NJ and you’ll know the meaning of shrinkage

[mvmojo]

Put the tee in the propane locker and run a separate line to each appliance. The last thing you want is a leaking fitting inside the boat where propane can collect in the bilge and go boom at some point!

[Cadence]

Originally Posted by mrybas

Hi,
I am adding a propane stove/oven and on-demand hot water heater.
There is a propane locker in the cockpit. The stove is in the galley, the hot water heater in an enclosed locker at the transom.
Can I add a T in the hose at the stove and run it to the hot water heater? Or will I need to run 2 separate lines from the tank?

The term enclosed locker scares the $hit out of me, with LP. I would tee off in the propane locker. The fewer fittings below deck the better.

[billgewater]

Whatever you do just make sure your insurance company is happy. Get it in writing. Signed document. Not an email.
You only make one mistake with gas.

[Mirage35]

I don't know the regulations so don't quote me. The thing that worries me - like others above - is the water heater in an enclosed locker. Maybe if it was drained like the propane locker it wouldn't be an issue.

Our on-demand water heater is in the V-berth, has a propane sniffer directly underneath it, and is only lit when we are actually using hot water. It passed survey five years ago but I've heard rumours that the rules have changed and it might no longer be considered acceptable.

And it and the stove have independent lines from the propane locker.

[bcboomer]

Originally Posted by mrybas

Hi,
Or will I need to run 2 separate lines from the tank?

YES!

And I hope there is an overboard drain on the locker.

[NorthCoastJoe]

Is the demand heater in a locker with a clear drain overboard and vented for exhaust and combustion air? I would not put any propane appliance in an enclosed space.

Unless it is a small one they really eat the gas when running. Make sure your line is large enough for the BTU. Put your "T" right at the regulator.

[foothillsailor]

A proper propane locker is supposed to be an airtight locker/container with an outlet at its base that would permit leaking propane gas to exit OUTSIDE of the boat. All connections (including Tee connections but excluding a flexible connection to a gimballed stove) are supposed to be within a propane locker. Thus to answer your questions: (1) yes, your T connection should be inside a propane locker thus requiring that you run two gas lines from the T connection to each gas-consuming appliance (2) your on-demand heater could be located in a separate propane locker if, and only if, it was located so that any leaking propane gas can only exit outside of the boat. Thus the on-demand water heater appliance would need to be located outboard of the hull (possibly at the transom as you suggest) with both its bottom drainage tube and its fresh air inlet (for the flame) located outside of the hull. I think that if the hot-water heater locker was located at the transom but inside the cockpit or hull that you might have a safety problem and would not pass an insurance survey unless you could clearly show that BOTH the intake and exhaust outlets (and by exhaust outlets I include both the exhaust outlets for the deadly carbon-monoxide AND any leaking explosive propane gases) are external to the both. Just my unqualified humble opinion ..... good luck ...it theoretically should be possible but I suspect will, practically, be difficult to do ..... suggest you look at a water system heated from the water heated by your boats engine (which already has a separate, safe and approved fuel delivery and gas exhaust system.

[Moontide]

Would definetly in a drain line at the bottom of the waterheater locker that drains outside the boat. Same as for tank storage. If there is a leak then want it to drain overboard.


Also, the locker for the heater will need vents or forced ventilation to replenish the O2 that the flame consumes.

[donradcliffe]

Be very careful to properly vent the hot water heater enclosure, both intake and exhaust. That is far more important than some T fittings in the propane line.