House Batteries Draining

[jrski]

We recently bought a 2005 Glacier and my son replaced the 3 house batteries. They drain down below 11.8 volts which I thought was the point where the LVD would cut off the current and not allow the batteries to drain down to 9 volts. I know virtually nothing about electrical or mechanical issues, but wouldn't the LVD cut off the current at 11.8 volts? Also, there has to be some kind of parasitic drain which is draining the batteries. Any help would be greatly appreciated.

Thanks,
jrski

[chin_k]

A functioning LVD should have a reasonable cutoff voltage, but there can be other accessories that by-pass the LVD, and the batteries themselves will also continue to drain down. I am not familiar with Glacier, but the LVD is there to give you time to charge the battery back up. If you do not notice the cutoff happened, it is not that useful anymore.

My comment is the following:
1, charge up the battery ASAP, before further damage happened.
2, find out why the relative new batteries continued to drain down even after the LVD does it job
3, try to avoid future occurrence by finding the offending appliance, and pay more attention to its use.

[jrski]

Yes, we are charging the batteries back up. We just don't know whether the LVD is working properly and what else may be draining the batteries that doesn't go through the LVD. To me, it would seem that everything that could possibly drain the batteries would have to go through the LVD, otherwise the LVD wouldn't have much value. We aren't intentionally using anything in the coach. We just got it home a few days ago after purchasing it and my son is making some needed repairs. He has put on all new battery cables and ground connections, we just can't figure out what may be draining the batteries.

[chin_k]

Sometimes people adds or modified the electrical system, so YMMV. Working from memory, for the original Concourse ~ year 2000, on the negative terminal, you should only have two things on the negative side. A 8 AWG wire going to the solar controller, and a 4 AWG going to the lug on the frame for grounding. On the positive terminal, you should only have 4 wires on it. A 8 AWG with a inline fuse going to the solar controller, a 4 AWG going to the battery separator under the hood, a 8 AWG wire and another smaller wire going to the white plastic resettable fuse box (with a 50 A and a 15 A fuse) before going to the LVD. If you have an ammeter, you can measure the current drain from each of the wires, and find out if there is any parasitic drain on it. Obviously, the solar controller will push the current down to the batteries. The battery separator, for example, does not get cut off by the LVD, but it suppose to disconnect the chassis battery from the coach battery when the voltage is 12.4 to 12.9 V or so.

In the reference sub forum, there are manual for some of the Chinook. If you do not have the manual with the rig, you may want to take a look and get familiar with the electric system.

[jrski]

Thanks, I'll pass this info on to my son.

[chin_k]

Thanks, I'll pass this info on to my son.

Very sorry about this, but I just realize you have a Glacier. The Glacier have much complicated electrical than the humble Concourse, so you should use the Glacier manual as reference for troubleshooting. If you do get an ammeter to measure the current draw, you may want to consider getting a Hall Effect clamp type for DC that you can simply clamp the sensor onto the wire. Most consumer version that I used many, many years ago are not that accurate for the low current situation, but maybe technology has improved, I just don't know. I am old school type that use shunt type ammeter

[BobW9]

We recently bought a 2005 Glacier and my son replaced the 3 house batteries. They drain down below 11.8 volts which I thought was the point where the LVD would cut off the current and not allow the batteries to drain down to 9 volts. I know virtually nothing about electrical or mechanical issues, but wouldn't the LVD cut off the current at 11.8 volts? Also, there has to be some kind of parasitic drain which is draining the batteries. Any help would be greatly appreciated.

You don't mention how long it is taking to drain down?

If the LVD isn't stopping it, then my first thought, on a Glacier, would be the Inverter is turned on. While not connected via the shore cable, try to plug something into an AC outlet and see if it works. I have a Concourse like chin_k, but I believe many/most Glaciers came with an inverter to convert the DC batteries to AC power for the outlets inside the coach. I've heard that the inverter (give the super-large wires normally used to attach an inverter to batteries) does not go through the LVD. The inverter uses quite a bit of power if turned on, even if nothing is using AC power. I don't know exactly where the inverter is, and from past messages on this board I'm not even certain it is in the same place on all Glaciers over the years (and is a combined inverter/charger for some of them). It should tell you in the Chinook manual for your Glacier, unless someone added/replaced it later.

My second thought would be to disconnect the positive cable (8 AWG usually) coming in from the engine, which goes through a solenoid (the battery separator). This wire is used to allow charging from the engine alternator to the house batteries when you drive, with the solenoid being there to stop draining when the engine is off. If the solenoid is bad, it might be allowing the house batteries to charge the engine starter battery continuously while parked. And if your engine battery isn't so good, maybe that drains the house batteries fairly quickly.

Anyway, that's where I'd start, since its easy to remove that one wire (two wires if testing inverter and solenoid at the same time). But check the house batteries voltage often while doing this - you don't want to let them drain too much again or you might ruin them.

Oh, and just in case, make sure the 3 new batteries say Deep Cycle on them. That is very different than the usual engine Starter batteries sold everywhere. Even if you meant to buy deep cycle, sometimes they sit on shelves mixed together with almost the same logos and lettering as the starters (especially if from the same manufacturer) - I came real close one time when at the last minute I found the ones I wanted were slightly too large and the sales guy brought out replacements he said would fit and at first glance were identical to the ones I'd picked... but he hadn't looked closely to see that they didn't state Deep Cycle on them. I almost walked out with them before I noticed.

[jrski]

Yes, my son said the battery separator is bad and he has ordered a new one. The 3 house batteries he put in are the Optima yellow top, deep cycle batteries. Thanks for the information. I'm glad I have my son to work on this thing, because I know absolutely nothing about electrical or mechanical stuff. He did a frame off restoration of a 1950's model Airstream trailer for a lady from Florida, plus he builds/restores old cars & trucks, so he has a quite a bit of experience doing mechanical work. Thanks again.