So when I bought my coach several years ago, it had what I believe is an early OEM rooftop AC, but I haven't been able to find out much info on it.
It's a "John E. Mitchell Co." unit rated at 13.5k BTU. It runs great, but uses a lot of power based on the fact that if it is above 95 degrees, it
will trip a 20amp breaker in the shorepower panel, even set to low. (For some reason though, the genset seems to run it fine.... Even on high when it
is 105+, it never trips the 20amp on the onboard panel whether on shorepower or the genset)
Anyway, I figured when we bought the coach, we would run the Mitchell AC for a few years, then get something newer down the road. Last year, we had a
week long trip planned to Florida in August, and I figured it would be a good time to change out the old AC, so I picked up a 15K btu Atwood Air
Command. But, one thing led to another, and I was never able to perform the swap before the trip, so we ran the Mitchell AC. It ran all the way from
here in Texas to FL on the genset, spent a week at the beach there (hooked to a 50amp service), and then ran it all the way home, and the Mitchell AC
never missed a beat.
So now, here we are, a year later, and this coming August we are again going to Florida, and I'm in the same boat of considering to change out the
Mitchell for the Air Command, (which has been sitting on a shelf since last year) but now based on how well the Mitchell unit ran, I'm sort of on the
fence on whether or not I should. My thoughts are this:
(Let me preface this with the fact that my coach lived most of it's life in a cooler climate than where we live here in Texas, so I don't sense the
Mitchell AC had much use)
1. The Mitchell AC is obviously built like a tank to last 45 years and still work great. Would a newer Atwood be more reliable? I realize it is
doubtful the Atwood would last 45 years, but say over the next 5 or 10 years, which unit would most likely give me less trouble? I'm also weighing
the fact that I have no problem doing minor repairs on either....
I could probably carry a spare run capacitor, or contactor or other spares for the Mitchell unit and swap them out if needed. OTOH, I assume the
Atwood is more dependent on electronics, so in the event that either one had an issue, I could probably fix the Mitchell with less down time... But
then, the Atwood is new, so it may run trouble-free for the foreseeable future, which makes repairing it a moot point.
2. The Mitchell unit is rated at 13.5K btu, the Atwood is 15k, but are the ratings equivalent? In my experience, it would not be unusual for things
that were built back then to be somewhat under-rated... Which unit do you think would ultimately cool better?
Those are the main things I'm considering... But also weighing in on my decision are the next few questions:
3. On high, the Mitchell unit is somewhat loud, but at low cool, it really is pretty quiet and low tends to do the job most times on our coach. The
compressor sounds more like an old sealed industrial refrigeration unit (which is probably what it is, based on the history of what I read on the
Mitchell Co.) than an AC compressor... I've heard the Atwood is quiet as well. Which do you feel would produce the least amt of noise?
4. The Atwood should put less load/stress on the genset, has a heatpump, wireless remote, etc.... The Mitchell can't match any of these.
So that's kind of where my head is at... Since the coach only has one AC, our vacation enjoyment is going to be pretty tied to how well the AC
performs, as the wife and our young children are not going to handle being in Florida, near the beach, in August in an un-air-conditioned coach....
Not to mention the drive back and forth through southern Mississippi, Alabama, East Texas, etc. with only the dash AC, which as we all know, does not
cool well stock.
I've also toyed with the idea of putting in the Air Command in the center, and adding a second unit in the rear in place of the fantastic fan we have
back there for some redundancy.... But I like the simplicity of having one unit, and it's less weight/drag on the roof... Since one unit seems to
cool my coach well, would you trade redundancy for simplicity?
Going with 2 units, I've read several of the ACs available now will fit in the rear opening mounted backwards, but does anyone know if an Atwood 13.5k
BTU unit would fit back there mounted forward? If not, are there any current units available that fit mounted forward?
Anyway, sorry for the long post and thanks in advance for your opinion, info, etc.
--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
It's a "John E. Mitchell Co." unit rated at 13.5k BTU. It runs great, but uses a lot of power based on the fact that if it is above 95 degrees, it
will trip a 20amp breaker in the shorepower panel, even set to low. (For some reason though, the genset seems to run it fine.... Even on high when it
is 105+, it never trips the 20amp on the onboard panel whether on shorepower or the genset)
Anyway, I figured when we bought the coach, we would run the Mitchell AC for a few years, then get something newer down the road. Last year, we had a
week long trip planned to Florida in August, and I figured it would be a good time to change out the old AC, so I picked up a 15K btu Atwood Air
Command. But, one thing led to another, and I was never able to perform the swap before the trip, so we ran the Mitchell AC. It ran all the way from
here in Texas to FL on the genset, spent a week at the beach there (hooked to a 50amp service), and then ran it all the way home, and the Mitchell AC
never missed a beat.
So now, here we are, a year later, and this coming August we are again going to Florida, and I'm in the same boat of considering to change out the
Mitchell for the Air Command, (which has been sitting on a shelf since last year) but now based on how well the Mitchell unit ran, I'm sort of on the
fence on whether or not I should. My thoughts are this:
(Let me preface this with the fact that my coach lived most of it's life in a cooler climate than where we live here in Texas, so I don't sense the
Mitchell AC had much use)
1. The Mitchell AC is obviously built like a tank to last 45 years and still work great. Would a newer Atwood be more reliable? I realize it is
doubtful the Atwood would last 45 years, but say over the next 5 or 10 years, which unit would most likely give me less trouble? I'm also weighing
the fact that I have no problem doing minor repairs on either....
I could probably carry a spare run capacitor, or contactor or other spares for the Mitchell unit and swap them out if needed. OTOH, I assume the
Atwood is more dependent on electronics, so in the event that either one had an issue, I could probably fix the Mitchell with less down time... But
then, the Atwood is new, so it may run trouble-free for the foreseeable future, which makes repairing it a moot point.
2. The Mitchell unit is rated at 13.5K btu, the Atwood is 15k, but are the ratings equivalent? In my experience, it would not be unusual for things
that were built back then to be somewhat under-rated... Which unit do you think would ultimately cool better?
Those are the main things I'm considering... But also weighing in on my decision are the next few questions:
3. On high, the Mitchell unit is somewhat loud, but at low cool, it really is pretty quiet and low tends to do the job most times on our coach. The
compressor sounds more like an old sealed industrial refrigeration unit (which is probably what it is, based on the history of what I read on the
Mitchell Co.) than an AC compressor... I've heard the Atwood is quiet as well. Which do you feel would produce the least amt of noise?
4. The Atwood should put less load/stress on the genset, has a heatpump, wireless remote, etc.... The Mitchell can't match any of these.
So that's kind of where my head is at... Since the coach only has one AC, our vacation enjoyment is going to be pretty tied to how well the AC
performs, as the wife and our young children are not going to handle being in Florida, near the beach, in August in an un-air-conditioned coach....
Not to mention the drive back and forth through southern Mississippi, Alabama, East Texas, etc. with only the dash AC, which as we all know, does not
cool well stock.
I've also toyed with the idea of putting in the Air Command in the center, and adding a second unit in the rear in place of the fantastic fan we have
back there for some redundancy.... But I like the simplicity of having one unit, and it's less weight/drag on the roof... Since one unit seems to
cool my coach well, would you trade redundancy for simplicity?
Going with 2 units, I've read several of the ACs available now will fit in the rear opening mounted backwards, but does anyone know if an Atwood 13.5k
BTU unit would fit back there mounted forward? If not, are there any current units available that fit mounted forward?
Anyway, sorry for the long post and thanks in advance for your opinion, info, etc.
--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
