Does Danhard A/C warrant solar panels?

MikewTV · 02-18-2008, 01:08 PM

Starcool III is apparently going to gradually phase out now and Danhard a/c will take its place. In the meantime both are available for a while. I am leaning towards Danhard since it would allow me to run the a/c when I'm taking my dogs around town on errands with me. (without a generator being needed.) But, this has raised a new question for me.

Should I get solar to offset the additional battery use the Danhard will demand? I was NOT going to get the solar set up since I'm on the east coast, often going to be blocked by trees when camping, and have a 30 amp hook up in my driveway anyhow. But, now I'm wondering if I should get the solar primarily because it would help assist with keeping the 2 batteries charged when I'm out in parking lots, running errands, etc. throughout the day.

Additionally, I'll run the Danhard frequently when on road trips in order to keep the dogs cool in back. I imagine this would make it that much harder for the alternator to be charging my 2 batteries while I drive. Would having solar help keep my 2 batteries charged in these circumstances?

Any opinions/advice on this from folks who are already using Solar (or not using it and think it's not needed?)

LoneStarJR · 02-18-2008, 03:44 PM

Actually, I don't think the solar will be enough. They (SMBtx) told me that the new AC draws more current than the van's alternator will produce and, if I'm driving with the Danhard running, the AC will drain the house battery after 8 hours. I, too, have dogs so I have similar concerns. However, I'm hoping that once I get the interior temp down to a reasonable level, the van's AC will probably be enough to maintain it and then I'll be able to shut off the Danhard while driving. But, this is only a guess as I've not yet tested this theory in the real world.

mmocken · 02-18-2008, 09:08 PM

I'd assume the solar will extend you A/C battery time and provide some shade to the PH rooftop...thus helping the A/C

**daveb** · 02-19-2008, 03:55 PM

I am surprised to hear that the Alternator will not keep up with the Air. I have the Starcool and was just above the limit with headlights, front air, wipers, inverter plus a stereo amp running at night. There are 2 alternators that Ford uses, but I think SMB orders the larger of the two. I can say this, I installed a 200 amp alternator and with everything in the van running, I can still get over 5 amps to the house battery when it can take it (maybe more). I have measured +17A on my link 10 monitor when the battery was about 3/4 low but was being supplemented by solar (around 4 to 5 amps). The draw from the Add-On air will be huge and solar will only make a dent. Even the 200 amp alternator will take some time to fill a low 4-D battery. On average, my 3-60 watt panels would bring a single 4-D battery up to near full from 3/4 low by 1 PM. This varied a lot with sun, shadow, and temperature. It takes only a couple of hours with the 200A alternator. I still recommend solar or at least a solar prewire as you might change your mind. Better re-sale also. Solar is nice because it keeps the batteries up to full while not over charging as it's well regulated. If you're close to shore power most of the time and you plan to use the add-on air for brief periods, you might want to look into a second 4-D, or a larger house battery. An on board generator able to run large loads might be a solution also. Good luck.
DaveB

LoneStarJR · 02-19-2008, 04:51 PM

From what I understand, the Danhard is different than the Starcool in that it's a completely separate, stand-alone system and totally electric. The good news is that it provides redundancy in the event one system or the other fails.

**daveb** · 02-19-2008, 08:43 PM

That is a nice option (not being tied to the vehicles A/C) but there's no way I would want a system that draws the house battery down while driving. But it's hot in my area and I want a low 70 degree climate when I drive. Everybodyâ€™s different. Mike never stated how big his batteries are, but he said he had 2. If a larger alternator would power it and keep a positive charge to the battery, I would prefer it over my old Starcool myself especially if it can run for a few hours from battery only. On the bad side you're swapping out the OEM alternator, a major part of the motor that affects many areas of the engine. I don't like giving Ford the ability to put blame on problems that might occur down the road even if it has nothing to do with the aftermarket alternator but I did it and haven't had a major trouble yet. I can always put back the OEM unit.
Dave.

MikewTV · 02-20-2008, 06:58 AM

This is all interesting to hear (and helpful.) I'm trying to avoid having to get a generator. It's not worth it to me. I had liked the idea of the danhard running for an hour when I was out doing errands with the dogs in the van. But now, I'm worried that I woudln't be able to run the rear a/c whenever I wanted to while driving. (errands, road trips, etc.) All for the benefit of having an hour of battery operation. This makes me wonder if Starcool III would actually be better since I can run it as much as I want on engine power.

As for batteries I am getting the second aux battery (aka: 2 batteries) but not the large 4D battery.

I realize regardless solar could be a good option to have. But, if I get every option that could be good to have - I'll go broke. Still, I was just told I got a rebate from ford which would just cover the solar. hmmm.

**daveb** · 02-20-2008, 01:19 PM

Mike, you should discuss this with SMB. Sorry but I donâ€™t know the stats on the Danhard. I might be wrong but I thought the Starcool III could run on battery only for a brief time???
With my rig I would not use my microwave (off a single 4-D battery only) for over a couple of minutes, or the battery would run very low before morning while using my normal load (Espar heater, Hydronic for an hour or so, some evening lighting, and the refrigerator). What is the draw compare to a microwave? If you're not running these items it might not be as much of a problem but I would want to know what kind of draw the A/C has and how your 2 batteries stack up against a 4-D. Large amp loads are not real kind to small batteries. If the 2 batteries are smaller that a single 4-D, I would think you might have problems. Really depends on how you use the vehicle on whether solar is needed. If the vehicle sits in full sun fore a few hours, solar is great. To supplement or offset the draw is good, but if the end result is a practically dead bank after an hour or so, you need another plan. 3-55W flexible solar panels will charge up small bank of AGM batteries fairly fast and a couple of 120W glass panels even faster provided the A/C (or any heavy load) is off. BTW I now run twin 4-D batteries. Finally, I now have enough reserve for most trips. IMO a single 4-D didnâ€™t cut it. But thatâ€™s for my needs. Others might disagree.
Dave.

MikewTV · 03-02-2008, 09:39 AM

Okay a little update on this and a question. I have decided to go ahead and go with the Danhard for certain instead of the Starcool. I still don't want a full solar install either. I have the option of shutting the Danhard off and running the engine on the road for about 45 minutes to recharge when the batteries are getting low (after 3 or 4 hours they tell me.) Or, if boondocking I could use a Honda Generator when needed. (probably won't do this either since I'm also one of those people who thinks generator noise is just such a blight on the whole camping experience.)

Now, one thing I am still considering is the solar pre-wire for a portable panel so that I (or the next owner) would have SOME solar option if need be without going full price and putting all the panels on the penthouse. Has anyone gone this way and found a portable panel set up they like that they could tell me about?