New rv questions

We just bought a 2005 Itasca Cambria.  The first owner had never used it and as such was not a good source of information.  Also, the owners manual is missing.  We just got back from a two night "shakedown" and have a couple issues.
1. When the coach batteries get low, what is the best way to recharge them?  Run the genset, or the chassis engine?
2. This one is equipped with a heat pump, which seems to work fine.  The only problem is that when I set the thermostat to " elec heat", both the heat pump and the propane furnace run simultaneously.  While this does provide a great deal of heat, I am guessing that is not the idea.
Can anybody help me with these issues?

Howdy guys - welcome to the rvforum and Winnebago family!

1. When camping with shore power, being plugged in with the charger running is best.  If you are boondocking, charging with the gen set is probably as good as running the engine - but this depends on the capability of your charger.  I'll guess a tossup unless noise and/or fuel usage is a consideration.

2. - Electric vs. gas heat.. with the thermostat in the electric heat mode, if the heat pump cannot attain or maintain the set temperature, the gas furnace will kick in automatically with a five degree difference.  You might go to bed with the electric heat option selected and wake up in the morning with the gas furnace running.  Not sure if this describes your situation.

Welcome to Winnebago world!!

both the heat pump and the propane furnace run simultaneously.

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John explained the LP "helping" the electric heat pump on occasion. If this happens when you first turn it on, it is because you have set the thermostat above the temperature differential and caused the LP furnace to kick into "help" mode. After both reach the set temp and shut down, only the heat pump should come on later when maintaining the set temp. When raising temp in our coach on getting up in the mornings, I adjust the thermostat desired setting to no more that 3 degrees higher than the room temp to get heat pump only. Then as the temp gradually rises, I will bump the desired setting up a few degrees at a time (never going more than 3 degrees over the current temp) until I get it to the temp I really want.

Also, the heat pump will "lock out" at low temp, and default to the LP heat (which will come on when room temp reaches 4-5 degrees below the setting). The lockout temp point varies with the humidity, but normally occurs with our heat pump in the high 30's. If humidity is high, raining, misting, etc, it may lock out in the low 40's.

crwallace1 said:

2. This one is equipped with a heat pump, which seems to work fine.  The only problem is that when I set the thermostat to " elec heat", both the heat pump and the propane furnace run simultaneously.  While this does provide a great deal of heat, I am guessing that is not the idea.
Can anybody help me with these issues?

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We did not like the way this worked on our Journey either, so we pulled the panel & put a toggle switch (i think in the white wire going from thermostat to gas furnace) to keep the gas heat from coming on.
Since these heat pumps do not have a defrost cycle, when they need defrosting, they just shut down, so if you have the switch off, you may wake up cold. Then you have to turn the added toggle switch on so the gas heat will work.

Or you can leave the gas switch off until the heat pump brings the temp up to normal,, then turn it on & it should work the first time it is needed.

If by "coach batteries" you mean the ones that start the engine rather than the ones that power the interior lights and such, your 2005 Cambria probably does not charge them from shore power or generator. Only the engine alternator will do that. The other batteries (referred to as house batteries) are charged whenever you are plugged into shore power or whenever the generator runs.

I guess I am getting tripped up by terminology.  If I want to charge the "house" battery while dry camping, would it be better to use the genset or to run the chassis engine?
  Thanks for the heat pump explanation.  Will try the 3 degree stepper method and see if that solves my problem.
  Thanks so much for your help!

crwallace1 said:

I guess I am getting tripped up by terminology.  If I want to charge the "house" battery while dry camping, would it be better to use the genset or to run the chassis engine?
  Thanks for the heat pump explanation.  Will try the 3 degree stepper method and see if that solves my problem.
  Thanks so much for your help!

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Most times the generator is the best choice for battery charging.  We boondock for 3 months every winter.  We have solar charging, but on cloudy days and for cooking we supplement with the generator to keep the batteries up.  We never let them go below half charge. The engine alternator probably does not put out a lot of current when idling, the converter/charger will put out it's rated output with the generator just like on shore power.  If you boondock a lot you might want to upgrade your converter/charger to charge the batteries in a shorter time and to get the advantage of a three stage charger.

crwallace1 said:

I guess I am getting tripped up by terminology.  If I want to charge the "house" battery while dry camping, would it be better to use the genset or to run the chassis engine?

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Really depends on the capability of your battery charger that runs off of shore power or gen set.  If your charger can put out 50-60 amps or more, like John says running the gen set is a good choice and you don't put wear and tear on the motor.

If you only have a 20-30 amp charger, then you might want to use the alternator to charge the house batteries.  I would suspect your alternator is at least 80 amps, probably more.

In my case, I always run the gen set for battery charging when dry camping - my charger is three-stage that puts out about 100 amps max.

John H. has a great tip for you - try not to discharge the batteries below 50% to preserve their life.

crwallace1 said:

would it be better to use the genset or to run the chassis engine?

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That would depend on a number of things, like how many amps your alternator puts out and what size generator you have. I have found with my rig if I need a fast charge with a lot of amps quickly I run the engine for like ten minutes. If I want to totally charge the house battery then I run the generator. Most people, I think, run the gen.

As to the the electric heat. If the differential is greater than the 5 degrees mentioned, both the electric and gas heat will come on the first time and bring the temperature to what you have it set on. After that the electric heat will come on by itself each time as long as it can maintain temperature..

The generator is probably the most accepted way to charge the batteries while dry camping other than having super solar...Good Miles

John Hilley said:

Most times the generator is the best choice for battery charging.  We boondock for 3 months every winter.  We have solar charging, but on cloudy days and for cooking we supplement with the generator to keep the batteries up.  We never let them go below half charge. The engine alternator probably does not put out a lot of current when idling, the converter/charger will put out it's rated output with the generator just like on shore power.  If you boondock a lot you might want to upgrade your converter/charger to charge the batteries in a shorter time and to get the advantage of a three stage charger.

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John, how in the world can you boondock for 3 months at a time?  You are really a "roughing it" camper.  We have done 3 weeks at time before with just electricity and thought we were really boondocking but that's nothing compared to you.  Having to scrimp on electricity for TV, air conditioning if needed or furnace otherwise, any small electric heaters, coffee makers,  electric blanket at night if that cold, electric hair dryer for the wife, and the list goes on.  My hat is certainly off to you and I bow to a real camper.

Allen

Wagonmaster2 said:

John, how in the world can you boondock for 3 months at a time? 

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He has done well!!  7-10 days is plenty for us now.  When we cruised in the Caribbean for 15 months on our sailboat, we spent a total of six weeks at a marina - the rest of the time we were at anchor (or making passages) living off our solar panel and wind generator (and diesel generator) - the major limiting factors for us were water and fuel.  Wish we had a water maker more than once.

Your genset is not going to charge your house batteries as fast as the alternator. No matter how much rating your charger has, the generator can't put out anywhere near the amperage as the alternator. To check this all you have to do is check the rating of the generator which is probably somewhere in the 35 amp range (before a fuse or breaker will trip).

What is best for the batteries isn't always what is fastest though, there are lots of variables such as battery type (AGM vs flooded), temperature, battery condition and so on. Also, the current level of charge will also make a big difference. Batteries being topped off aren't going to benefit from a high amp charge rate because more than likely, the charger is going to go into float mode rather than the bulk high rate charge.

Quite a few alternators will easily put out more with an engine idling than the generator running at idle. Remember, your generator isn't going to run a low speed when it has a heavy draw on it. While the generator uses less fuel than the engine, it also takes longer to produce the same amount of power. The alternators are designed to produce lots of power even at low engine speeds. Don't forget that the diesels are turning very slow compared to gas engine to begin with. Alternators on gas engines are set to produce maximums at higher engine speeds than a diesel will ever run at.

The bottom line is that some experience will tell you what is best for a variety of conditions. Sometimes the generator will be best, some times the alternator will be best.

If you try to stick with one charging method it might be easier but you'll lose the advantages of experience and using the best method for the general condition.

Finding the ratings of your generator and alternator is something worthwhile knowing in any case.

Your genset is not going to charge your house batteries as fast as the alternator. No matter how much rating your charger has, the generator can't put out anywhere near the amperage as the alternator. To check this all you have to do is check the rating of the generator which is probably somewhere in the 35 amp range (before a fuse or breaker will trip).

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There are elements of fact in both opinions on this. Few people directly charge from a generator 12v output, and, as Crackofdawn says,  that is often very low amperage anyway (8-15A is typical). However, powering the RV's converter or inverter with the generator gives you the same charge capacity as you have on shore power, and that typically in the 45-70 DC amp range. Big difference.

The engine alternator needs to run well above idle speed, perhaps 1200 rpms, to put out much amperage, but when it does it really pumps it out, maybe 100+ amps in a car or truck and 200 in a big motorhome. Just idling the engine, though, will likely get you only 5-10 DC amps. You won't charge very much or very quickly at that rate.

Great thread for my problem this morning...
Paul (afchap) said:

Also, the heat pump will "lock out" at low temp, and default to the LP heat (which will come on when room temp reaches 4-5 degrees below the setting). The lockout temp point varies with the humidity, but normally occurs with our heat pump in the high 30's. If humidity is high, raining, misting, etc, it may lock out in the low 40's.

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I heard the heat pump on several times last night and woke to a coach that was about 4 degrees colder than the thermostat was set.  Looked thru all the documentation on the coach and never found out about the "lock out" feature.  Was about ready to look into my extended warranty and a mobile RV repair.

The heat pump did activate later in the morning when the temp got up to above 40. 

Planned a three week trip within Florida and thought that I could beat the cold...  Last year we were out on our boat in the Bahamas this time of year and the temperature cooperated.  I know that I'm whining, but it ain't suppose to be this cold in FL.

Go ahead and whine!  ;D  The heat pump in our stick house is usually running on the heat strips early in the morning.  We are more than ready for spring - had sleet/snow/frozen fog/rain/etc and lots of very cold temps this winter.

You should be able to order a replacement Owner's Manual for your 2005 Cambria (Winnebago Part No: 132000-27-005) from any Winnebago dealer.  Lichtsinn Motors (http://www.lichtsinn.com/rv-parts.aspx) is a highly recommended parts source if you don't have another source near you.