The Great Bilge Pump Debate, 2023 Edition

[jviss]

Greetings!

There are many "traditions" regarding electricity and system management on sailboats. At one time it was the generally accepted practice that one had two house batteries and alternated use of them on a daily basis; hence, the 1-2-BOTH-OFF switch. That practice is fading into obscurity. Another ancient practice that I believe is still dominant is that bilge pumps be powered directly from the house battery, so that if the 1-2-B-O switch is OFF, or the main breaker is OFF, the automatic pump will still be energized, to spring into action should the boat begin to flood.

I never understood the logic of this, and have never heard a compelling reason for it. The only reason I was given once was that if someone saw that your pump was running, they would alert someone, or go ahead and try to save your boat. I find this dubious. And, in the case of my boat, you can't see the pump output, anyway.

So, I am inclined to not follow this practice, or at least to connect the pump to the batteries through a low voltage disconnect, so I don't end up with a flood and a dead and damaged house bank.

What say you?

 

[Jacktar]

If your boat sinks because the bilge pump is not working on auto direct from battery or water rises above battery banks (usually low in bilge somewhere) depleting the battery bank is the least of your worries.

 

[FastOlson]

I have known several surveyors over the decades, and they do not like to see any connection to the batteries that violates ABYC standards requiring a very close breaker or fuse, sized to the wire.
More important tho is having the means to immediately disconnect / de-energize all circuits in case of fighting a fire. So it's important to have a "master switch" that does what it sez.
IMHO the practice of leading a clump of wires to a battery terminal kind of migrated up from small boats that never had a panel or "system" in place, especially older boats. Those are really fire hazards IMO.

We have always had the bilge pump wired thru a labeled breaker on the main DC panel, standard in our '88 boat.
As for having zero direct-wired things to our house bank we do have a sensing wire for our Smartgauge, our analog meter, and one circuit for our furnace. The later is to avoid having furnace operation carelessly interrupted by someone harming its circuit board if they turn off a breaker rather than properly powering it down.
ALL of those few battery connections are fused right at the battery terminal with a BlueSeas terminal block that mounts on the post.

Back to the opening question - our DC panel is normally energized and the bilge pump(s) are active. Also our refrigeration!

(Like our 80's Ericson, I would be rather surprised if a Tartan was originally built with a non-ABYC compliant circuit for the bilge pump. )

 

[dmax]

When I went to visit a boat I bought a week after sailing it home from CT, there was water up to the floor boards and the battery was dead (old style 2 single batteries). The engine raw water intake hose had popped off (whoever winterized it didn't tighten the clamp). I pumped it out and had to replace the battery but I'm sure the boat would have sunk if the bilge pump wasn't active. A low voltage cut-off sounds like a good idea.

 

[jviss]

If your boat sinks because the bilge pump is not working on auto direct from battery or water rises above battery banks (usually low in bilge somewhere) depleting the battery bank is the least of your worries.

The bilge pump isn't going to save the boat, it's only going to delay the sinking.

 

[Ralph Johnstone]

So, I am inclined to not follow this practice, or at least to connect the pump to the batteries through a low voltage disconnect, so I don't end up with a flood and a dead and damaged house bank.

Somebody should come up with an idea where there is something that automatically keeps a charge on your batteries while you're away from your boat. Then if the bilge pump comes on to save you from a failed shaft seal, you're not going to run down the batteries.

 

[jviss]

I'm sure the boat would have sunk if the bilge pump wasn't active.

How can you be so sure? Was the bilge pump running when you got to the boat?

 

[rgranger]

The bilge pump isn't going to save the boat, it's only going to delay the sinking.

About 6 mo ago I was sitting on my dock enjoying a cold one and heard the pump on a friends boat cycle on 4 times in the span of two beers… I called him… we saved his boat.

 

[jviss]

About 6 mo ago I was sitting on my dock enjoying a cold one and heard the pump on a friends boat cycle on 4 times in the span of two beers… I called him… we saved his boat.

Nice! I should be so lucky. My boat's on a mooring.

 

[Dalliance]

I wouldn’t call direct connection to batteries an ancient practice, I‘ld call it prudent, and that’s how I have mine set up. It’s not just about power management, it’s also about redundancy and fool proofing of safety systems.

My set up is this:
Bilge Pump 1 is lower in the bilge, on a float switch, with fuse protected connection to battery 1 and it’s on a cycle counter so it can’t mask a small problem until it’s an emergency. Cycle counters on automatic bilge pumps are kind of a soapbox issue for me.
Bilge Pump 2 is higher in the bilge as a hopefully never needed back up, also on a float switch, with fuse protected connection to battery 2 and it has a painfully loud alarm. Discharge is dock side in the hope that someone would see water coming out where is normally doesn’t, hear the alarm and call me or the harbor master. Dubious? Maybe, but it’s a small dock, everyone knows each other and we look out for each other.

The shore power charger maintains the battery charge, so not much chance of batteries going dead at the dock as long as the shore power is actually on and the charger is working. No guarantees there. The charger could crap out or shore power could go out or, more likely, accidentally be turned off. So direct connection to separate batteries, both at the dock and away, still makes sense to me.

Under normal circumstances, the only water in my bilge comes from the stuffing box and the ice box. I dry the bilge when I close up the boat and it’s usually still dry when I return a week later. So some might say that even a float switch is unnecessary, but normal circumstances aren’t a given. Stuff happens. Is the second bilge pump overkill? Hopefully, but it gives me peace of mind.

 

[jviss]

I wouldn’t call direct connection to batteries an ancient practice, I‘ld call it prudent, and that’s how I have mine set up. It’s not just about power management, it’s also about redundancy and fool proofing of safety systems.

My set up is this:
Bilge Pump 1 is lower in the bilge, on a float switch, with fuse protected connection to battery 1 and it’s on a cycle counter so it can’t mask a small problem until it’s an emergency. Cycle counters on automatic bilge pumps are kind of a soapbox issue for me.
Bilge Pump 2 is higher in the bilge as a hopefully never needed back up, also on a float switch, with fuse protected connection to battery 2 and it has a painfully loud alarm. Discharge is dock side in the hope that someone would see water coming out where is normally doesn’t, hear the alarm and call me or the harbor master. Dubious? Maybe, but it’s a small dock, everyone knows each other and we look out for each other.

The shore power charger maintains the battery charge, so not much chance of batteries going dead at the dock as long as the shore power is actually on and the charger is working. No guarantees there. The charger could crap out or shore power could go out or, more likely, accidentally be turned off. So direct connection to separate batteries, both at the dock and away, still makes sense to me.

Under normal circumstances, the only water in my bilge comes from the stuffing box and the ice box. I dry the bilge when I close up the boat and it’s usually still dry when I return a week later. So some might say that even a float switch is unnecessary, but normal circumstances aren’t a given. Stuff happens. Is the second bilge pump overkill? Hopefully, but it gives me peace of mind.

Whether one is at a dock or not, and on shore power not, makes a difference. I think in your case, and perhaps in most cases, the alarm is the thing, not so much the pump. Most common bilge pumps won't stay ahead of a serious flood.

 

[Dalliance]

Whether one is at a dock or not, and on shore power not, makes a difference. I think in your case, and perhaps in most cases, the alarm is the thing, not so much the pump. Most common bilge pumps won't stay ahead of a serious flood.

Agreed. They’re meant to handle incidental water. They may buy some time with a more serious leak, and two will buy more time, but they’re not going to stay ahead of something catastrophic.

 

[dlochner]

Somebody should come up with an idea where there is something that automatically keeps a charge on your batteries while you're away from your boat. Then if the bilge pump comes on to save you from a failed shaft seal, you're not going to run down the batteries.

Perhaps you have heard of this new invention called a photovoltaic cell? They can be grouped together to make enough energy from the sun to keep batteries charged. Many boats down here have them.

 

[Scott T-Bird]

I never understood the logic of this, and have never heard a compelling reason for it. The only reason I was given once was that if someone saw that your pump was running, they would alert someone, or go ahead and try to save your boat. I find this dubious. And, in the case of my boat, you can't see the pump output, anyway.

So, I am inclined to not follow this practice, or at least to connect the pump to the batteries through a low voltage disconnect, so I don't end up with a flood and a dead and damaged house bank.

What say you?

I can't find any logic in not having a properly wired and protected float switch that is "always on" when the house panel is switched off. I'm not really thinking about the boat sinking due to a catastrophic hose or shaft seal failure - I agree there are circumstances where the bilge pump can't save a sinking boat. I'm thinking about leaks that might develop from a much more mundane source. A slow leak from above-the-waterline sources such as a water system leak or rain water that could eventually flood the saloon floor during a one-week or two-week absence, causing all kinds of unnecessary damage that would have been avoided if the bilge pump had simply been activated just once or twice.

The reality is, the circumstance of my boat sinking due to some catastrophic hose failure is about as unlikely to occur on my boat as an electrical fire due to the bilge pump or float switch wiring being faulty, so, what would be the point in not having a float switch for the bilge pump "always on"?

 

[jviss]

Somebody should come up with an idea where there is something that automatically keeps a charge on your batteries while you're away from your boat. Then if the bilge pump comes on to save you from a failed shaft seal, you're not going to run down the batteries.

Ralph, you never cease to amaze me.

Sure, you can have solar. But if the shaft seal you're referring to is a dripless, and the bellows fails spontaneously, it's not likely a conventional bilge pump will stay ahead of the the flood. If it's a conventional stuffing box, sure, but those won't leak at a rate that would sink a boat in a week, or even a month.

 

[jviss]

I can't find any logic in not having a properly wired and protected float switch that is "always on" when the house panel is switched off. I'm not really thinking about the boat sinking due to a catastrophic hose or shaft seal failure - I agree there are circumstances where the bilge pump can't save a sinking boat. I'm thinking about leaks that might develop from a much more mundane source. A slow leak from above-the-waterline sources such as a water system leak or rain water that could eventually flood the saloon floor during a one-week or two-week absence, causing all kinds of unnecessary damage that would have been avoided if the bilge pump had simply been activated just once or twice.

The reality is, the circumstance of my boat sinking due to some catastrophic hose failure is about as unlikely to occur on my boat as an electrical fire due to the bilge pump or float switch wiring being faulty, so, what would be the point in not having a float switch for the bilge pump "always on"?

That's a good point, Scott, but I would do so through a low voltage disconnect. And, I don't think activating the pump "once or twice" would be removing enough water that would have damaged your boat.

 

[Ralph Johnstone]

​

Perhaps you have heard of this new invention called a photovoltaic cell? They can be grouped together to make enough energy from the sun to keep batteries charged. Many boats down here have them.

And we shall call these new and marvelous devices "Battery Chargers."

Can I have an "Amen" to that ?

 

[Scott T-Bird]

Amen! I assumed there was a tongue-in-cheek!

 

[Scott T-Bird]

low-voltage disconnects ... my wife is already rolling her eyes at all the reasons I find to poke around in every recess within the boat. With a charger that is always connected when at the dock, that one is even pretty low on my priority list!

 

[dmax]

How can you be so sure? Was the bilge pump running when you got to the boat?

The boat was sinking when I got there, water above the floor boards is pretty close to sunk anyway, things start to get damaged, it was hours away from flooding the engine. It drained a fully charged battery. I'm sure.