Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 21-02-2013, 14:09   #1
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Efficient battery driven air condition for Lagoon 450 catamaran

Looking for expert advice. Installing this fall in the Ft. Lauderdale are.

The Lagoon 450 factory air condition for a 4-cabin version has 48,000 BTU. 4x 8,000 BTU for the cabins and 16,000 BTU for the salon.

My energy production / storage
1500W solar - delivering approximately 600 Ah during summer days
A small 3-5 KW generator ( not finalized yet)
1000 Ah LFP batteries (80% usable)
2 x Victron Multi Plus 3000

Air condition usage pattern
Only for the 4 cabins, not for the salon
Most days there will be only 2 cabins used
We can tolerate warm cabins. Have been for a long time with just fans.
Run only to cool cabins off a little in the evening before going to bed
Use batteries and inverters to run air con


Initial thoughts
Install 16k-24k BTU chiller in engine room
Use soft start or VFD to avoid inrush current spikes
Run insulated water lines to all 4 cabins
Install individual air handler in cabins

Does anybody have experience in this area?
__________________

__________________
roetter is offline   Reply With Quote
Old 21-02-2013, 14:30   #2
Do or do not
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 8,868
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by roetter View Post
Looking for expert advice. Installing this fall in the Ft. Lauderdale are.

The Lagoon 450 factory air condition for a 4-cabin version has 48,000 BTU. 4x 8,000 BTU for the cabins and 16,000 BTU for the salon.

My energy production / storage
1500W solar - delivering approximately 600 Ah during summer days
A small 3-5 KW generator ( not finalized yet)
1000 Ah LFP batteries (80% usable)
2 x Victron Multi Plus 3000

Air condition usage pattern
Only for the 4 cabins, not for the salon
Most days there will be only 2 cabins used
We can tolerate warm cabins. Have been for a long time with just fans.
Run only to cool cabins off a little in the evening before going to bed
Use batteries and inverters to run air con


Initial thoughts
Install 16k-24k BTU chiller in engine room
Use soft start or VFD to avoid inrush current spikes
Run insulated water lines to all 4 cabins
Install individual air handler in cabins

Does anybody have experience in this area?
I have one of those newer 18kBTU all-in-one units that are the same size as the 16kBTU. I also have a 3kW Victron Quattro. All that is 240V 60Hz. SOmetimes I lose shore power without noticing (asleep) and switch to inverter. After 10-15 minutes my 1,200Ah Trojan L16's battery bank has gone down enough to trigger low voltage alarms. It just takes too much too quickly from my batteries.

But with LFP this should not be a problem. We always run the genset for 1-2 hours every night, making water, charging batteries and running the A/C, before shutting that all down and sleep with just a fan. Taking the heat out of the boat after sundown is great.
__________________

__________________
s/v Jedi is offline   Reply With Quote
Old 21-02-2013, 14:39   #3
Registered User

Join Date: Jul 2011
Location: Australia NSW south coast
Posts: 616
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Are the air cond units you are running at the moment 240vac powered? I am more involved with motorhome lithium ferrous house power but we do a have a few members of our local group the use their roof top air cond for a few hrs to take the peak temp down a bit to allow for an afternoon nap or a good nights sleep, all powered from the battery packs via an inverter and solar recharging.

The chiller system will lower temp but not the humidity, it will make that worse as a lower temp can't support as much water vapour so it would start condensing on walls, windows, in cupboards and on you wil you try to sleep. Often the temp isn't the problem, it's the humidity that makes sleeping difficult.

T1 Terry
__________________
T1 Terry is offline   Reply With Quote
Old 21-02-2013, 14:51   #4
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Quote:
Originally Posted by T1 Terry View Post
Are the air cond units you are running at the moment 240vac powered? I am more involved with motorhome lithium ferrous house power but we do a have a few members of our local group the use their roof top air cond for a few hrs to take the peak temp down a bit to allow for an afternoon nap or a good nights sleep, all powered from the battery packs via an inverter and solar recharging.

The chiller system will lower temp but not the humidity, it will make that worse as a lower temp can't support as much water vapour so it would start condensing on walls, windows, in cupboards and on you wil you try to sleep. Often the temp isn't the problem, it's the humidity that makes sleeping difficult.

T1 Terry
Could you explain why the chiller system would not lower the humidity? Seems odd to me.

I thought the air handler would cool the air far enough for some moisture to condense out and collect in the drip pan. Then as the cool air mixes with the warm air the relative humidity would be lowered somewhat.
__________________
roetter is offline   Reply With Quote
Old 21-02-2013, 14:54   #5
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Quote:
Originally Posted by s/v Jedi View Post

I have one of those newer 18kBTU all-in-one units that are the same size as the 16kBTU. I also have a 3kW Victron Quattro. All that is 240V 60Hz. SOmetimes I lose shore power without noticing (asleep) and switch to inverter. After 10-15 minutes my 1,200Ah Trojan L16's battery bank has gone down enough to trigger low voltage alarms. It just takes too much too quickly from my batteries.

But with LFP this should not be a problem. We always run the genset for 1-2 hours every night, making water, charging batteries and running the A/C, before shutting that all down and sleep with just a fan. Taking the heat out of the boat after sundown is great.
Is your Victron set to 240 or do you use a step up transformer? I want to use two Multis in parallel to supply coffee maker, micro wave, etc with 110V 60 Hz, and use a step up transformer to drive the air con.

Do you use a soft start for the compressor motor?
__________________
roetter is offline   Reply With Quote
Old 21-02-2013, 15:10   #6
Do or do not
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 8,868
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by roetter View Post
Is your Victron set to 240 or do you use a step up transformer? I want to use two Multis in parallel to supply coffee maker, micro wave, etc with 110V 60 Hz, and use a step up transformer to drive the air con.

Do you use a soft start for the compressor motor?
Hmm.. the preferred way to this is to have:

1 - 240V genset (instead of 110V). Often you can jumper L1 and L2 in series instead of parallel. Do not connect the neutral at all, so that the load on the genset is always perfectly balanced.

2 - Victron isolation transformer with step-up/down so that you can take either 110V or 240V from shore but always output 240V. Leave the output floating, i.e. do not connect a ground to one of the legs.

3 - Use an EU model Quattro (or two in parallel) which is sold in the US, and re-configure it for 240V/60Hz. This is a simple software setting. With the same software you set the parameters for battery charging etc.
Connect both genset and isolation transformer to the Quattro.

4 - On the Quattro output you have 240V floating, i.e. no ground connected to either leg. Keep it like that; any boat ground system is only connected to the ground pins in outlets, the ground connections on gear etc.

5 - Now the trick: get a Victron Auto-transformer. This is a small, light unit, that is connected to the 240V Quattro output and it creates a new Neutral, so that you have 120-0-120 for the regular 120/240V service. This auto-transformer takes care for any imbalance in load between the two 120V legs.

The above works perfectly and is also how Victron endorses it.

I think my CruisAir 18kBTU came with soft-start as standard? But it might also be the change from 120 to 240V that makes so much difference that I find it soft-start-like.
__________________
s/v Jedi is offline   Reply With Quote
Old 21-02-2013, 19:48   #7
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Quote:
Originally Posted by s/v Jedi View Post

Hmm.. the preferred way to this is to have:

1 - 240V genset (instead of 110V). Often you can jumper L1 and L2 in series instead of parallel. Do not connect the neutral at all, so that the load on the genset is always perfectly balanced.

2 - Victron isolation transformer with step-up/down so that you can take either 110V or 240V from shore but always output 240V. Leave the output floating, i.e. do not connect a ground to one of the legs.

3 - Use an EU model Quattro (or two in parallel) which is sold in the US, and re-configure it for 240V/60Hz. This is a simple software setting. With the same software you set the parameters for battery charging etc.
Connect both genset and isolation transformer to the Quattro.

4 - On the Quattro output you have 240V floating, i.e. no ground connected to either leg. Keep it like that; any boat ground system is only connected to the ground pins in outlets, the ground connections on gear etc.

5 - Now the trick: get a Victron Auto-transformer. This is a small, light unit, that is connected to the 240V Quattro output and it creates a new Neutral, so that you have 120-0-120 for the regular 120/240V service. This auto-transformer takes care for any imbalance in load between the two 120V legs.

The above works perfectly and is also how Victron endorses it.

I think my CruisAir 18kBTU came with soft-start as standard? But it might also be the change from 120 to 240V that makes so much difference that I find it soft-start-like.
Interesting idea! I have to draw that one up.i

I had an autotransformer on my previous boat. My boat was US model (120V) but I travelled in Europe with several European appliances plus NA appliances. I had two shore power connections, one 110 the other 220V. I could switch the transformer to the input or output of the 120V Multi. That way I could plug in either voltage and always had both voltages available from shore or from the inverter alone. I reprogrammed the Multi to deliver 50 Hz as the washer water pump was the only item I had that did not like 60 Hz. Just had to disconnect from 120-60 and restart the Multi to get the 220V-50Hz for the washer water pump. All other items had no problem running on either 50 or 60 Hz.
__________________
roetter is offline   Reply With Quote
Old 21-02-2013, 23:45   #8
Registered User

Join Date: Jul 2011
Location: Australia NSW south coast
Posts: 616
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by roetter View Post
Could you explain why the chiller system would not lower the humidity? Seems odd to me.

I thought the air handler would cool the air far enough for some moisture to condense out and collect in the drip pan. Then as the cool air mixes with the warm air the relative humidity would be lowered somewhat.
In you opening post you mentioned a chiller system and a closed loop insulated water system wuth heat exchangers in each cabin, did I understand that part correctly? If I have got it right, the water can't be cooled to freezing so the heat exchanger in each cabin would be above freezing point, it would collect a bit of moisture but most of it would be still in the air. An air cond removes the water by freezing it, then it melts off as the system cycles, if the unit is too big for the room the same thing happens, the air is chilled before it's dried and the same uncomfortable clamy feeling is the result.

T1 Terry
__________________
T1 Terry is offline   Reply With Quote
Old 22-02-2013, 00:12   #9
Registered User

Join Date: Mar 2012
Location: On board in Alanya, Turkey
Boat: Hunter Legend 420 Passage
Posts: 540
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by roetter View Post
....My energy production / storage
1500W solar - delivering approximately 600 Ah during summer days
A small 3-5 KW generator ( not finalized yet)
1000 Ah LFP batteries (80% usable)
2 x Victron Multi Plus 3000..........
We run a 12,000 BTU reverse cycle air con/heater from our 1050 Ah Lifeline AGM bank via a Victron Muiltiplus with no soft start. It works fine for just an hour or so. If we need it for longer, or the batteries are already low we run the genny as well. Not much point running the genny if the batteries are already above 90% because its not going to put much back into them.

If you've still not decided on a genny look at the Fischer Panda 5 Kw DC genny - with a continuous output of 272 amps @ 12 volts. We have the 4kw version which has been great.

One thought on you solar output - is 600Ah/day a bit optimistic, or have you actually measured that? More likely to be 400-500 Ah.
__________________
sailinglegend is online now   Reply With Quote
Old 22-02-2013, 00:14   #10
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Quote:
Originally Posted by T1 Terry View Post
In you opening post you mentioned a chiller system and a closed loop insulated water system wuth heat exchangers in each cabin, did I understand that part correctly? If I have got it right, the water can't be cooled to freezing so the heat exchanger in each cabin would be above freezing point, it would collect a bit of moisture but most of it would be still in the air. An air cond removes the water by freezing it, then it melts off as the system cycles, if the unit is too big for the room the same thing happens, the air is chilled before it's dried and the same uncomfortable clamy feeling is the result.

T1 Terry
Yes my initial thought is a chilled water system as you would find from Dometic. http://www.dometic.com/enus/Americas...Chilled-Water/

Are you sure about that? As far as I understand all large yacht AC systems are chilled water systems. On large boats several chillers are Located in the engine room and the water is pumped to the air handles. Throughout the yacht. I would think that someone with a $30m yacht would not tolerate a humid environment.
__________________
roetter is offline   Reply With Quote
Old 22-02-2013, 00:18   #11
Registered User

Join Date: Nov 2011
Location: Fethiye Turkey
Boat: Lagoon 440
Posts: 3,164
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Rolf we have the MAR-IX Chilled water system on board, it works very well no complaints.

Cheers
__________________
"Political correctness is a creeping sickness that knows no boundaries"
Lagoon4us is offline   Reply With Quote
Old 22-02-2013, 00:31   #12
Registered User

Join Date: Oct 2011
Location: Winter Bahamas - Summer BC
Boat: Lagoon 450, Bavaria Vision 40
Posts: 599
Quote:
Originally Posted by sailinglegend View Post
We run a 12,000 BTU reverse cycle air con/heater from our 1050 Ah Lifeline AGM bank via a Victron Muiltiplus with no soft start. It works fine for just an hour or so. If we need it for longer, or the batteries are already low we run the genny as well. Not much point running the genny if the batteries are already above 90% because its not going to put much back into them.

If you've still not decided on a genny look at the Fischer Panda 5 Kw DC genny - with a continuous output of 272 amps @ 12 volts. We have the 4kw version which has been great.

One thought on you solar output - is 600Ah/day a bit optimistic, or have you actually measured that? More likely to be 400-500 Ah.
Thanks for the numbers. That helps. I assume with your AGM's you mostly work with 50-90% SOC giving you about 400Ah to work with. Not all for AC of course. I hope to get a little more from the the LFP , up to 800Ah usable.

I usually used 200 Ah during the time solar was not charging for things that are not AC. So I should have about 600 Ah's max for AC.

Which Multi are you using?

I like the specs of the Fischer Panda but hear so many bad things about reliability and warranty. Maybe that only applied to older units. I don't know. The 5KW DC Panda was exactly the one I was considering, but bad experiences turned me off. Would like it if it turn out to be a god genny. It is small and light. Don't know what to think, but don't want to turn this into a heated Benny discussion.

Had 950W solar installed before. Got in summer over 400 Ah's. In winter it was more around 200. Depended if I was not too lazy to tilt the panels. In winter I will not need the AC though. So 600Ah's just for AC at night should not be too optimistic. I would probably run the genny for an hour before bed to get the AC over the reallynhard work, then switch to battery. Had a great Outback charger with the panels. Plan the same charger again.
__________________
roetter is offline   Reply With Quote
Old 22-02-2013, 01:48   #13
Registered User

Join Date: Mar 2012
Location: On board in Alanya, Turkey
Boat: Hunter Legend 420 Passage
Posts: 540
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by roetter View Post
...Which Multi are you using?

I like the specs of the Fischer Panda but hear so many bad things about reliability and warranty....
Sorry I should have said it was a 12v 2.5Kva 120 amps Victrom Multi-Plus. 6 years old now, as is our FP Genny.

Yes FP have had a lot of trouble with their gennys but they are now getting much better, especially the DC generators which are more reliable and need less maintenance since they don't have to run at a constant speed to provide a 50 or 60 cycle output no matter what the load. So the DC genny runs much quieter when delivering a small load. Here in the UK they are widely used by the RNLI - our lifeboat rescue service. Not many cruisers are using them!

A lot of PFs problems have been water ingress into the exhaust causing loss of compression. This has happened to us twice, but that has been down to my installation, even though I followed Vetus's instructions on the waterlock/muffler/swan neck. . In a yacht it is very easy in a big swell for water from the waterlock to flow back into the exhaust. This happens if the waterlock is not installed inline with the generator. PF have modified their exhaust mixing elbow to provide a swan neck in there too.

When I installed my system there was only one paragraph on the waterlock installation in the very large manual. Now there are 15 pages. In six years I have had two relays fail - cheap replacements from local car shop, and rebuilt my exhaust mixing elbow and removed the head twice. Now I keep a spare set of gaskets.
__________________
sailinglegend is online now   Reply With Quote
Old 22-02-2013, 03:23   #14
Do or do not
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 8,868
FP is always "changed and good now", yet the owner has had the same old trouble twice already with correctly installed exhaust...
__________________
s/v Jedi is offline   Reply With Quote
Old 22-02-2013, 04:30   #15
Registered User

Join Date: Mar 2012
Location: On board in Alanya, Turkey
Boat: Hunter Legend 420 Passage
Posts: 540
Re: Efficient battery driven air condition for Lagoon 450 catamaran

Quote:
Originally Posted by s/v Jedi View Post
FP is always "changed and good now", yet the owner has had the same old trouble twice already with correctly installed exhaust...
You've missed the point - just to put down FP.

Fischer Panda demand a better installation procedure than the instructions Vetus provided. FP are trying to be very helpful to their customers - and to help the sometimes useless installers of their equipment.

Please don't waste time with posts that add nothing, or are you just trying to get your post-count up. So far you have averaged nearly 4 posts EVERY day for the last 4 years. 48 posts just yesterday - get a life!

This is an Engineering and Systems forum where we try and help each other with feedback of our experiences, not just offer opinions. If you want idle chit-chat then please find another forum.
__________________

__________________
sailinglegend is online now   Reply With Quote
Reply

Tags
battery

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 07:17.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.