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[chazwood]

I have a over the road ac system that is getting harder to maintain. (Mci 92) thinking of dumping it.
I have a new delco 50dn and two heat pumps in the basement. (about 15 amps each)
what kind of inverter should I use to connect to the delco and run the two airs while on the road?

also since I'm a bit of a "sparky-tard".... perhaps someone could tell me how to connect it?

[Oonrahnjay]

I have a over the road ac system that is getting harder to maintain. (Mci 92) thinking of dumping it.
I have a new delco 50dn and two heat pumps in the basement. (about 15 amps each)
what kind of inverter should I use to connect to the delco and run the two airs while on the road?

also since I'm a bit of a "sparky-tard".... perhaps someone could tell me how to connect it?   

      Hey, Chaz, I'm famous for not bein able to figger out how those little electrictron things hold hands but the basic is ~15 amps @ 120 volts is ~1800 watts.  But what's required to start the heat pump?  If a 2500 watt inverter has enough reserve to start the heat pump, plus enough reserve to handle a little battery charging at the same time, plus losses from heat and just plain electrical inefficiency (mostly heat losses), then you'd need 2500 watt (also called a 2.5 Kilowatt or Kw) inverter for each heat pump.
      Some companies offer a 4Kw (4000 watt) inverter for 24v (to match your 50dn) and I don't have a lot of experience with 24v inverters but I'd be *very* surprised if 4000W is enough to usefully carry two 1800 watt heat pumps, even if the starting loads aren't an issue.  Maybe it would work, but I'd be surprised if it did; in real life, you just gotta have a buffer above the minimum or nominal computed wattage.
      Just a WAIG, you might need one 3Kw inverter for each heat pump (one 3k @ 24v input) to be sure to have enough power in all conditions -- but that's a VERY w-a guess. 

      Maybe people who know more will comment.   BH   NC    USA
      I'm pretty sure that a 50dn will generate enough power to run a nominal 2X1800 watt load but you're talking about pulling some serious power out of your engine to do it. 

[pvcces]

chazwood , I think that the Xantrex SW4024 would handle the loads. As far as connecting it all together, I can think of some things that you need to do right.

(1) make sure that the inverter will not overheat in whatever compartment that you put it in.

(2) make sure that your wiring is sized right.

(3) you will need an interconnect between your house and start bank if you are going to be able to use any charging or power you have available. For example, if you stop for the evening and you want to plug into a pedestal. Or you want to run your AC on your generator.

(4) GFCI operation may cause problems; this may force you to choose a different inverter. Just remember the basics; all the grounds are always tied together. Both power leads have to be switched to whatever power source you are using.

(5) make a good drawing before you build.

(6) you should decide whether you want to lose all of your AC powered electrical in the event that the inverter does not run.

Try some searches on these boards; there is a lot of good info available.

Good luck.

Tom Caffrey

[Oonrahnjay]

   chazwood , I think that the Xantrex SW4024 would handle the loads. As far as connecting it all together, I can think of some things that you need to do right. 

      Again, I don't know much but I agree with Tom's points.  A Xantrex SW4024 is rated at 4Kw (4000 watts) at 24V input.

[chazwood]

Thanks bunches guys you are the bomb! Turns out a little brass collar and solder stopped the leak in the condenser ( I think I bumped it while replacing my fan) the bad news is I used about 20 pounds of r-22 to fill it back up. Ouch. Hopefully it will do as good as it did before. The info you gave me will still come in handy when I contemplate how to run my two basement airs at the pedestal and boon docking.