Guess I should eat a little crow here…

Well…Just went back & reviewed your posts & noticed your limit of 5000 watts for 5 seconds…(guess I missed that before)

That will probably scratch the 20 or 24 K idea…And it really does limit you to a 12K system if we go by the lock rotor figures as start up amps, and subtract 65% for SmartStart…

Still…I know I have started a older 16K unit with standard (not SmartStart) start capacitor & relay reliably, on a Heart 2000 watt inverter in a 37' Hunter…But wouldn't want to advise you to go more than what the figures tell….

Yes it's my feeling that "Regular" starting amps will be lower than LRA…But again I'd hate to see you get equipment all the way down to Tahiti, install it & not have it work…The SmartStart does also take about 10 starts to calibrate itself to the system…

I will say that with the Marine Air controls…The pump & fan start before the compressor, so that would be a plus over the Cruisair controls which start the fan first, but the pump starts at the same time as the compressor.

Taking all that into consideration…It's your call…Sorry if I mislead…  

Steve~

Post edited 10:30 am – May 26, 2011 by Steve Pooler

Francois said:

Steve,

I checked the VTD16  and EQ16 spec sheets, it appears that EQ16+blower draws less than VTD16:

-VTD16 5.1amps + blower0.78amps= 5.88 amps…No…The Vector Turbo Self Contained unit is FLA rated as all in one…Blower & Compressor = 5.10 amps…

Very close to the Split system…and the difference was likely a small voltage difference at the time each was tested/rated.

 

-EQ16 4.1 amps+blower TVE16 0.78amps=5.08 amps…Yes correct…They don't rate "Split Systems" as all in one because you could use two or more air handlers to equal the Btu of the compressor…More air handlers may mean more amps total because of the multiple blower motors.

 

Maybe I misunderstood but the blower FLA line is seperate from the VTD16 FLA.

Do you confirm ?

François

 

Remember though…No matter which system, Self Contained or Split…You must add pump amperage to the system total…But, They don't all start at the same time, so the surge (in-rush) amperage is reduced…

 

Instead of 3 (or more) motors starting at once…They are staged as Pump first, Blower/s next, then Compressor…Well depending on control model…The blower/s & pump could reverse in order but you get the idea…

 

Steve~

Francois said:

Hi Steve,

 I am still wavering between different options,

1° option: I am really interested in the idea to have 2 separate blowers TVE8 connected to a single EQ16 split unit:

-providing a better distribution of cool air in the cata

-2 8k blowers will be less noisy than a singe 16K, correct?…Likely true but with todays digital controls & programmable low fan speeds it's not really an issue…

-I will use smaller air ducts, grilles and 8K blowers are more compact than 16K…Yes to both statements…

-FLA unit+2blowers=4.3+2*0.83=5.96amps=1371w at 230v/60Hz

BUT, there is something strange in the spec : TVE8 FLA is higher than TVE16 !! (0.83 for 8K and 0.78 for 16K).

Is it a mistake?…Yes I see that…I would say that it must be a Typo, but can't confirm that till the factory opens tomorrow (It's a Holiday here today)

 

2°)Another option: is to have 2 independent EQ10 each connected to a single TVE10 blower:

-better flexibility: I could run only 1 unit at a time when PV charging (anchored) or weak charging rate, and both units when ashore or motor-sailing or good charging rate

-I could use a single pump for the 2 units, correct?…Yes with the installation of a pump relay…You would use the PR3X : http://www.dometic.com/5a47cda…..5827.fodoc

-the units could have a staged start when both running, correct?…Yes & No…The blowers do not sequentially start…They will always start together per system…But will start at a different time than the pump…The compressors can be set to stage start…but will only do that if there has been a power interruption…It is possible (but unlikely) that they may try to start to start together when cycling on the thermostat…

-1 unit running : FLA 1 EQ10 + 1 TVE10=2.6+0.61=3.21amps=738w  at 230v/60Hz (less pump, which is really acceptable for the inverter !)

-2 units running at the same time: 738*2=1477w (less pump/s which is still acceptable for the inverter )

BUT the thing is: could I start the second unit while the first is allready running, using my 2000w inverter ?

 If I use smart start device, I have rated that: 35% of EQ10 LRA=22*35%=7.7amps=1771w inrush power added to 738w gives 2509w (lees pumps), which may be critical for the inverter…Yes but remember…Not all will in-rush at the same time during a normal start…Blowers can be set to run all the time at reduced speed (automatically) and thus reduced amperage draw when the cabin is to temp….In your application I would not program the control/s for the fans to cycle with the compressors…

Second option gives more flexibility but is the more expensive, all the more if I have to get a more powerfull inverter…You will also need 2 digital controls/keypads…

Have you ever installed this kind of installation ?…Yes…Many times, but not on an inverter…Though it is one of my preferred system setups….You are right…It is much more flexible, and will likely do a better job all around.

regards,

François

 

Steve~

Post edited 10:06 am – May 31, 2011 by Steve Pooler

Francois said:

Dear Steve,

do you have drawings of your installations in catamaran with 2 separate units?…Sorry…No drawings on stuff I've done…

I guess the compressors are in the engine rooms (together if single pump) or separate (one in each engine room), what is the best installation?…They don't have to be located in the same engine room, but if using a single pump you again need a pump relay & water must be run to the opposite location for the other system…

A 2 pump system gives redundancy, but with your power constraints it may not be an option…

Where are the blowers installed? in lockers? behind walls? under settee?…Any of these locations are fine…Just consider the ease of your duct runs & service of that unit in the given location…

Is it recommended to use tees on air ducts course to spread cold in different rooms (galley+cabin)?…Yes…These are what we recommend and carry (Click on PDF catalog once there) http://www.airmsi.com/msi_004.htm

 

If the blower spread in different rooms, where is the best place for the return grille, in which area (cabin or galley)?…Generally speaking, closer to the unit is better but…You do need a return path from each cabin that has a discharge vent…Otherwise if sealed up, that cabin will pressurize, and air flow will reduce into that cabin…Not to mention that the air needs to be "conditioned"

 

How long air ducts can reach for a 10K? And with how many tees ?…This & many other answers in the links below…

 

Also, I looked at the air filter/purifier with UV lamps, I wonder how often it needs to be cleaned in very humid weather ?…No cleaning is required…They are free flow so they will not restrict, and are in the discharge path thus after the system's return air filter/s…

 

 Is it truly efficient against mildew? Can it be used only with the blower fonction without compressor running?…Yes they can be utilized with just the fan running…In fact they advise that they be wired to full time power (main unit breaker) as each power cycle shortens bulb life….The control will have a de-humidify mode which brings on the system with compressor to remove humidity for moisture control…I can't say how much they would remove alone.

 

regards,

Francois,

PS: I hope I am not annoying with all my questions….

 

Francois~   These should keep you busy for a bit:

 

http://www.dometic.com/enus/Am…..r-Systems/

 

http://dometic.com/FileOrganiz…..-Turbo.pdf

 

http://www.dometic.com/FileOrg…..ration.pdf

 

Bring on any more questions  

 

Steve~

SmartStart is only active during Start up of the compressor…It can't help with running load.

The SmartStart retails for $450.00

The only thing you can do to help that generator is to be sure you always have full water flow and a clean condenser coil (water coil)…No scale buildup.

Steve~