Run down house battery R21EC

[rt11002003]

My 2014 R21EC had a run down house battery, 7.6v, when I bought it. Supposedly, the batteries had been fully charged before delivery. Started engine, Garmin wouldn't engage, thruster wouldn't work. Prior owner then said m/b thruster had run battery down. Replaced battery. Charged all batteries w/on board charger; voltage readings 13+v on all batteries while charging; 12.8 otherwise. Boat has AC with two additional group 24 batteries.

Things seemed OK for a couple of days. Yesterday, house battery was down to 7+v. All switches off since 12-15-15.

PO said something about house battery not charging from alternator. Makes no sense to me. Doesn't the system work by using automatic charging relays (ACR)to charge start battery, when ACR senses start battery charged moves charge to next battery and continues until all batteries charged? Doesn't that happen to be the way for both alternator and battery charger?

I've never dealt with ACRs in the R21EC before, can't really recall how my other tugs were wired.

Is the thruster on/off switch wired directly to the house battery? Is the on/off switch under the helm console wired directly to the house battery?

Any thoughts about where the most likely current drawing device is? I'm sure this isn't a unique issue.

 

[knotflying]

I am not as familiar with the charging system on the 21. However, here are my thoughts. The alternator most likely goes to the house battery and the engine battery then gets charged when the relays see that the engine battery needs charging. If the engine battery is below a specified voltage the relays will not allow a charge because they suspect that the battery has an issue. If you have house batteries that are joined and you have a bad cell in any of the batteries then the culprit will discharge the other batteries. Just because after a charge you are reading a full charge it does not mean that the batteries will hold their charge.
After a full charge the batteries should rest a few hours and then a load test should be done on each battery to ensure that they are all in good shape. My initial thought is you have a bad battery in your grouping. Doing a full charge and then a load test will eliminate that possibility. After you do this test we can explore the next steps to check.

 

[Pilotnavigator]

There seems to a lot of discussion on batteries running down for no apparent reason on the 21ec. I have yet to trace all my boat wires and document them from the factory but I did have all the battery negative line disconnected for the winter. I checked the current draw with a good DC clamp amp meter over the summer to confirm my usage. I made sure that with all the switches off there was no current draw on the batteries. Also since you have three house batteries, as I do , make sure the positive and negative lines from the house batteries come from each end of the battery group. As opposed to the leads coming from the end battery. This will help ensure an equal drain on the full battery set. Also check that the temperature sensor and the alternator charging line goes to the house batteries. As the discussion always seems to be about the house batteries going flat while the starter is always good, verify the proper connections and then test the drain with the system off. If you confirm the current is zero with ALL switches and breakers OFF then you may have a bad battery. Then you must charge the system and the disconnect all battery negative lines. Come back in a day and verify battery voltage. Any battery not at full voltage would indicate a bad battery. Or you could take each battery to a shop and have them load tested, but that is more work getting them out. If you replace a battery make sure they are all the same type and capacity. I changed mine from the factory to be all group 27 AGM. This way I could put two in the aft locker and two on their side in the engine area. It is not good to attach two older partially worn out batteries with a new one. If you can solve the problem now then when you have to replace the battery pack do all the batteries at the same time. Try not to draw them down below 50 percent and they should last many years. Add up your amp hour usage, I don't have AC so my only main draw is the fridge at 3 amp hours, and some led lights, and the VHF, when at anchor. My house battery capacity is 190 amp hours so I can use half that, 95 amp hours before I start the engine. If I budget 4 amp hour used for 12 hours a day. Fridge compressor running half the time, and some lights, then I can go two full days on the batteries. 4x12=48, 95\48=2 days
A 21ec owner on here last year was have the same problem you are having but he sold the boat before he posted any solution, perhaps we are talking about the same boat. I always pop the house circuit breaker under the engine cover when I leave the boat. And turn off the house and thruster switches in the cabin. For me that cuts all house power. You need to verify that is the case for you. If not you have to fine which wire is still carrying current, that is we're a good clamp meter comes in. You will find the circuit in a few minutes by checking each wire starting at the batteries and working forward until you fine the single device that is still getting power when it should be off. I know the stereo for one is still charged when the house switch is off, it only gets disconnected if the breaker under the engine is popped. Just press the red button. When you come back reset with setting the yellow bar, by pressing it back into the housing. This breaker does not protect the thruster.

Hope that gives you a place to look for a start

 

[Two killicks]

This is great info for me as, I do not have much experience with the electric stuff in general.

John, if The thruster, and main switches are off the bildge pump still work. if you close the breaker in the engine compartment, do you know if the pump will still work?

 

[Pilotnavigator]

The bilge pump,is connected direct to the battery. It should not be drawing power unless running, this is one wire to check with the meter to ensure there is no problem with the switch. Mine never runs so I filled the bilge with water for a hose to check. Ther should be a fuse in the line to the pump. But with all the negative lines removed even the bilge pump is off, so only do this when on the trailer, when the plug is out!

 

[Two killicks]

Great info thanks John

 

[rt11002003]

Thanks for all your responses. The house battery, that I had on an independent charger yesterday, had 12.6 volts at noon today, after sitting all night disconnected. I put it on the independent charger again today and left it for four hours. I then put it back into the boat system and left the boat charger running. All batteries were charging at 14.9 volts when I left. We'll see what happens over the next couple of days.

I intend to check every circuit. I have three VOMs so surely I'll figure it all out. Sooner, or later. My formal electrical training was done on a USAF B-47 bomber about 60 years ago. Have had lots of practice on a variety of systems since then. Seems like every system I look at is different from every other system,

 

[Pilotnavigator]

It really is the current you have to figure out, not the volts. Invest in a good DC clamp meter to read current. You do not have to open up up the circuit. AC only are cheaper but you need a DC one. Around $100 or more. In a few minutes you can check each line in the boat. Clamp around the house battery line first the positive and then the negative, they should read the same and should be zero. If not move further down stream to find the location where the current is going. It may be more than one location so the currents should sum to the reading you got at the battery, or at least very close to it. Within 200th of an amp. 0.02 amps.

 

[mlull]

Make sure your ACR is wired correctly. Sometimes they are not...

 

[SGIDAVE]

There are parasitic loads on the house battery even with factory installed switches off. On Barry's (BAZ) 2016 model 21EC he describes a similar problem. When the house battery gets drawn down too low...the problem gets worse...

The Blue Sea ACR does not operate normally when one of the batteries to which it is connected (the now very low house battery/ies). When the voltage drops too low, the ACR won't close (or "combine") the batteries as it normally would. This is NOT a defect with the ACR but rather a safety feature to prevent paralleling dissimilar batteries (i.e., you don't want to parallel 6V and 12V batteries). So, when one battery gets TOO LOW, the ACR won't combine and send charge to that very low battery. Hence, the situation of having a 21EC that will start up just fine, but the house battery is stone-dead and not getting any juice from the alternator like it normally would.

Pilotnavigator is right, you NEED a clamp on meter which will measure DC current. You will find either your battery is defective OR there are small loads on the house battery even with "all" switches off.

The solution is to install a switch BEFORE the ACR or any other possible loads.

The bilge pump MUST be direct-wired to the battery. This does not normally create parasitic load on the battery unless it has the type of float switch that "tests" resistance every minute or two. I don't think the bilge pump/float switch combo Ranger uses is of this type. It has not been my experience anyway.

Let us know what you find Gene!

dave

 

[rt11002003]

One of my VOMs has the clamping device. I've been charging the batteries so that I'm working with a charged system when I start looking for amperage draw. I plan to start my search this pm.

I've had to contend with replacing a battery, checking out the automatic bilge pump circuit, trying to put in a device to allow me to pump antifreeze into the raw water system; we've had freezing nights already. 😱 I've found one thing I dislike about the Volvo compared to the Yanmar; that's no flushing fitting in the Volvo compared to the Yanmar. I put a fitting in the Volvo system; it won't work! :x

And, my depth sounder has quit. Since I've got all the cushions, carpets, table and PFDs in the v-berth, all of that has to come out so I can trouble shoot and work in that area, if needed. :shock:

I had given up on buying another boat because of all the problems involved. Then, my wife talked me into this one; said I needed something to do. She's right about having something to do. 🙁

 

[knotflying]

I really think before you go crazy looking for what is causing your batteries to discharge you should make sure all of the batteries are in good shape and are able to hold the charge. If all checks out okay then start to systematically check for parasitic draws.

 

[rt11002003]

Several days have passed since I began a journey thru my electrical system. The run down house battery was replaced and all the batteries have been fully charged and have held their charge for three days. I've run my VOA Meter thru most of the circuits and have only found one circuit with amperage flow with the system in normal shutdown mode, the stereo memory circuit. All the batteries have been checked for charging voltage, once with the charger running and then with alternator running. It appears all works as it should, including the ACR's.

I'll keep an eye on things; and report any further changes, should any occur.

 

[harry ames]

If you have one of those silly bilge pumps that does go directly to the house battery, it doesn't shut off with the battery master switches. On my Classic, the bilge pump fires up and runs a few second every few minutes. It will only continue running if it senses water going through and will run 'till the bilge empties. That type of bilge pump is a common cause of mysterious battery drainage.

Just a thought. I have a separate bilge off switch on the Classic that I turn off when the thing is on the trailer.

 

[rt11002003]

Harry, it is normal for bilge pumps to be wired with a switch that allows one to turn the bilge pump "on" (manual operation) and another position usually labeled "automatic". The "automatic" mode is directly wired to the battery, protecting the boat when no one is around. (IFF everything works as they should.)

If I kept my R21EC on my trailer, I'd pull the bilge drain plug and leave the bilge pump in the "automatic" position. With the drain plug removed, the bilge should remain dry and the pump should not run. However, should the drain opening get clogged, then the bilge pump can keep water from accumulating and causing problems. Over the years I've seen many boats on trailers with the bows up, full of water because they couldn't/didn't drain.

I keep my water on the water with the bilge pump switch in "automatic". In heavy rain, even with a bimini top, the boat takes on a lot of water. When I was having battery and bilge pump fuse problems, several times I found the bilge with water almost to the high water alarm. Fortunately, I live 5-10 minutes from my dock and can keep an eye on the boat in bad weather. As soon as a covered slip is available, I'm putting my boat in one. I think that's the better solution than depending on covers which sometimes fail.

 

[harry ames]

My bilge pump, in the automatic position runs every few minutes for a few seconds. It doesn't use a float or other type of water detector. It just turns on and pumps and if no water is present after a few second, it turns off. So if I left the bilge pump on when on the trailer, it would run down the battery pretty quickly. I'm fortunate to have an on-the-hard storage that has a metal roof over it so water will not be a problem with rain. I don't like the periodic turn on method of running a bilge pump, I'd rather have one that actually senses the water. The periodic pump would be sure fire though, if battery was no issue. I'm putting the bilge pump on my list of do it better and may increase the capacity while I'm at it.

My battery management on the C-Dory was to have a house battery and with the twin outboards, two starting batteries. When cruising, I'd let the automatic charge handling do its thing, keeping first the starting batteries up, and then automatically switching in the house battery. At night away from a dock, I'd shut down the two staring batteries completely and run the boats systems just on the house battery. I always had start capability that way. On the R21, I don't have any sophisticated charge management, so I'll do it myself. I'll turn the 1/2/both/off switch to the start battery and watch it charge at the helm panel, when it is looking good, I'll switch to the house battery and watch it come up. At night, I'll follow the C-Dory procedure and use only the house battery. However, an ACR relay is also on my list of "better."

 

[Jake]

My bilge pump, in the automatic position runs every few minutes for a few seconds. It doesn't use a float or other type of water detector. It just turns on and pumps and if no water is present after a few second, it turns off.

On the R21, I don't have any sophisticated charge management, so I'll do it myself. I'll turn the 1/2/both/off switch to the start battery and watch it charge at the helm panel, when it is looking good, I'll switch to the house battery and watch it come up. At night, I'll follow the C-Dory procedure and use only the house battery. However, an ACR relay is also on my list of "better."

You learn something new every day. Never heard of a bilge pump that just runs every few minutes and I assumed all Ranger Tugs had an ACR. You just can't assume anything when it comes to boat electrical systems. 🙂

 

[rt11002003]

harry ames, is there a timer that turns the pump on and off? I've seen pumps with remote sensors; and I've seen pumps with internal sensors. In fact, I saw one with an internal sensor and it cycled just like you're talking about because there was just enough water in the outlet hose and it was leaking back and activating the pump.

Live and learn. 😱 One expects to find different ways of doing things on boats from different mfg.'s; however, one would hope a mfg. would keep things the same on a single boat line. I've had a 2007, a 2009 and now own a 2014 R21EC; they've all had differences.

 

[harry ames]

No, it apparently has a time inside. Dumb way to do it, but a sure fire way to keep the boat dry if you have infinite battery.

 

[SGIDAVE]

harry ames, is there a timer that turns the pump on and off? I've seen pumps with remote sensors; and I've seen pumps with internal sensors. In fact, I saw one with an internal sensor and it cycled just like you're talking about because there was just enough water in the outlet hose and it was leaking back and activating the pump.

Live and learn. 😱 One expects to find different ways of doing things on boats from different mfg.'s; however, one would hope a mfg. would keep things the same on a single boat line. I've had a 2007, a 2009 and now own a 2014 R21EC; they've all had differences.

Remember, Harry's boat is a 1997, so it's likely on it's third, forth, fifth, etc bilge pump. My point is that previous owner's of his boat have more to do with his situation than the 'factory.'

RULE is known to produce a line of "automatic" pumps which THEY describe in their manual as:

How Fully Automatic Bilge Pumps Work:

Rule Automatic bilge pumps eliminate the need
for a separate float switch to activate the pump.
Once power is supplied, starting and stopping is
completely automatic. The pump checks for water
every 2 ½ minutes by turning on for a second and
measuring load against the impeller. If water is
present, the pump remains on until the water is
removed. Thereafter the pump resumes its 2 ½
minute check cycle. The automatic pumps feature
two positive leads: an automatic (brown) and a
manual override (brown with a white stripe).

I don't care for this type of pump since it will reliably deplete the battery to which it is appropriately connected. Using a pump with an automatic function based on a standard float switch is a more reliable solution.

.dave