Marine 12v air conditioning

[Steve_C]

I will be installing 3 of the Mabru 17K BTU units next month in my Cat. I will report back on the efficiency. I was hoping for 24 volt units, but unfortunately they are not released and apparently won't be for some time. I still believe the inverter driven variable speed units will provide my required efficiency.

[Budreau]

Originally Posted by Steve_C

I will be installing 3 of the Mabru 17K BTU units next month in my Cat. I will report back on the efficiency. I was hoping for 24 volt units, but unfortunately they are not released and apparently won't be for some time. I still believe the inverter driven variable speed units will provide my required efficiency.

Any updates Steve? How much solar and lithium do you have in there too. Thanks

[boatpoker]

Originally Posted by 170122

Mabru units are not made with commonly available shelf parts, the blowers are made with Permanent magnets brushless motors, ceramic bearings are needed to avoid friction and rust due to moisture, the reversing valves is specially designed for R134 pressures with 12V solenoids, the air coils are custom copper with copper antimicrobial, anti-electrolysis fins,

What the heck are anti-electrolysis fins ?
It can remove your first mates facial hair ?

[Russian007]

Clark and Emily have a new video up for their solar powered 12/24v 5000btu one off AC. Apparently they've partnered with a 3rd party for manufacture. The parts and materials look excellent. The footprint for the compressor/evap is only 10"x10"x14". <200 watts, >7 coefficient of power. Salt H2o cooled. Dunno what the price is. Disclaimer: C&E's vids are longish, have poor production value and his wife doesn't parade and tease in her thong bikini but content trends excellent. So you've been warned.

[Rumrace]

Ask if there is a deal for two. My air has crapped out
Sounds like an easy to manage amp demand.

[poiu]

Originally Posted by Russian007

Clark and Emily have a new video up for their solar powered 12/24v 5000btu one off AC. Apparently they've partnered with a 3rd party for manufacture. The parts and materials look excellent. The footprint for the compressor/evap is only 10"x10"x14". <200 watts, >7 coefficient of power. Salt H2o cooled. Dunno what the price is. Disclaimer: C&E's vids are longish, have poor production value and his wife doesn't parade and tease in her thong bikini but content trends excellent. So you've been warned.

You don't see a COP generally higher than 4.5 even from the most advanced manufacturers and from the most expensive units. I think 7 is a mistake.

[fxykty]

We’re looking at installing an air conditioner to cool our sleeping cabin and salon - 12-16K BTU seems about right. If it can dehumidify the air that’s half the battle, and a heating cycle would be nice as well.

We’ve pulled out a generator and would use that location under our berth for the air conditioning unit, and already have available throughulls for water intake and output, plus AC-sized wiring for power in that location. Ducting to our cabin and the salon would be relatively easy.

I don’t understand why, if you already have a 2KW+ inverter (ours is 5KW), you wouldn’t choose an AC powered unit? The power used is roughly the same, but the wire sizes running from the load bus bar to wherever the air conditioner is located can be a fraction of the size with an AC powered unit.

Am I missing something?

We’re on the east coast of Australia and we would like to install before the end of winter.

[s/v Jedi]

Originally Posted by fxykty

We’re looking at installing an air conditioner to cool our sleeping cabin and salon - 12-16K BTU seems about right. If it can dehumidify the air that’s half the battle, and a heating cycle would be nice as well.

We’ve pulled out a generator and would use that location under our berth for the air conditioning unit, and already have available throughulls for water intake and output, plus AC-sized wiring for power in that location. Ducting to our cabin and the salon would be relatively easy.

I don’t understand why, if you already have a 2KW+ inverter (ours is 5KW), you wouldn’t choose an AC powered unit? The power used is roughly the same, but the wire sizes running from the load bus bar to wherever the air conditioner is located can be a fraction of the size with an AC powered unit.

Am I missing something?

We’re on the east coast of Australia and we would like to install before the end of winter.

It must be expected efficiency savings plus remove the need for a “large” inverter. So for boats with the now popular solar + lithium + big inverters doing electric galleys etc. this removes one important reason for DC powered A/C.

I am not sure how energy efficient DC powered vs variable RPM AC powered is but I think it will be the same. This gives DC powered a 5% advantage because inverters are about 95% efficient.

[valhalla360]

Originally Posted by Acadia

Full - 100amps

So roughly the same as your standard 120v marine air/con.

That's around 1200w ...which is pretty much what our 120v unit pulls.

In terms of total watt-hour draw, if you can get away with the lower output, it simply means the 120v unit likely will cycle resulting in similar total watt-hour usage.

About the only advantage I can see is the peak output needed to kick over the compressor is likely lower but there are simple solutions for that.

[valhalla360]

Originally Posted by boatpoker

What the heck are anti-electrolysis fins ?
It can remove your first mates facial hair ?

Wouldn't the "anti" imply it puts the facial hair back on or grows it?

[FlyingScot]

Originally Posted by fxykty

We’re looking at installing an air conditioner to cool our sleeping cabin and salon - 12-16K BTU seems about right. If it can dehumidify the air that’s half the battle, and a heating cycle would be nice as well.

We’ve pulled out a generator and would use that location under our berth for the air conditioning unit, and already have available throughulls for water intake and output, plus AC-sized wiring for power in that location. Ducting to our cabin and the salon would be relatively easy.

I don’t understand why, if you already have a 2KW+ inverter (ours is 5KW), you wouldn’t choose an AC powered unit? The power used is roughly the same, but the wire sizes running from the load bus bar to wherever the air conditioner is located can be a fraction of the size with an AC powered unit.

Am I missing something?

We’re on the east coast of Australia and we would like to install before the end of winter.

From my research the 12VDC Mabru is the most efficient. The Velair and Frigomar are the next best, both of those being AC. Velair/Frigomar have the advantage of being truly variable speed which should almost entirely eliminate cycling. The Mabru being soft start but then just two speeds.

We are going with Mabru. One reason is the pure efficiency (BTU removal per watt), the second being you don't load up your inverter leaving headroom for other things. I'm sure the loaded up inverter will put out a lot of waste heat and heavily used will wear out faster. Third, it will still work even if your inverter doesn't.

[poiu]

Originally Posted by FlyingScot

From my research the 12VDC Mabru is the most efficient. The Velair and Frigomar are the next best, both of those being AC. Velair/Frigomar have the advantage of being truly variable speed which should almost entirely eliminate cycling. The Mabru being soft start but then just two speeds.

We are going with Mabru. One reason is the pure efficiency (BTU removal per watt), the second being you don't load up your inverter leaving headroom for other things. I'm sure the loaded up inverter will put out a lot of waste heat and heavily used will wear out faster. Third, it will still work even if your inverter doesn't.

The Mabru is actually equally efficient as the Velair and Frigoboat. Allowing for inverter losses the DC model may be 8% more efficient. If compared when run off shore or genset power then the Mabru is the least efficient, because you have battery charger losses of about 8%. For that you have to pay double the price to buy it. Not remotely worth it in my view as you will never (in a lifetime) claw that back in generator diesel savings in battery only mode. If they sold it for the same price as the others, especially if they did a 24v model then it would probably be the one to get.


Also note that the Mabru does not modulate much. From full power to 70%. The others modulate down to 30%, which results in very quiet operation and reduced temperature fluctuations.

[FlyingScot]

Originally Posted by poiu

The Mabru is actually equally efficient as the Velair and Frigoboat. Allowing for inverter losses the DC model may be 8% more efficient. If compared when run off shore or genset power then the Mabru is the least efficient, because you have battery charger losses of about 8%. For that you have to pay double the price to buy it. Not remotely worth it in my view as you will never (in a lifetime) claw that back in generator diesel savings in battery only mode. If they sold it for the same price as the others, especially if they did a 24v model then it would probably be the one to get.


Also note that the Mabru does not modulate much. From full power to 70%. The others modulate down to 30%, which results in very quiet operation and reduced temperature fluctuations.

First, everyone may have a different situation. We don't have a built in generator, but if you do, the cost of the generator is way higher than just the price of the diesel to run it. Way way higher.
So let's say the losses are exactly same from the inverter or battery charger, which is a better time to be more efficient? I'd say when you don't have an abundance of power is the better time to use less power!

Your second point on cost. I agree that the Mabru costs more. But double? Show me where you can buy a Frigomar (not Frigoboat) variable speed inverter aircon for half. The Velair is the cheapest of the three.
I have had great experience with Andre@theyachtrigger.com. He has sold all three of brands and should be able to help give great advice.

I'll skip to your last point for a moment. Did you read what I wrote?
Here it is again "Velair/Frigomar have the advantage of being truly variable speed which should almost entirely eliminate cycling. The Mabru being soft start but then just two speeds." So on this point we agree.

Now let's talk efficiency: My research shows differently than yours. Would you like to show your research?

They both make 7K btu/hr units, so lets compare them:
https://www.frigomar.com/en/products...inverter-bldc/
Frigomar says it uses 470 watts on 120v to make 7K btu/hr.

Mabru states 28 amps @ 12v. Let's call it 12.5, so 350 watts.

Now which is actually more efficient?

But wait, there is more... The Mabru includes the seawater cooling pump in that number? How much does your seawater cooling pump use? I bet it is a lot! It can be upwards of 150-200w.

You already mentioned inverter losses, but let me give you a real world example by adding all of it together. My buddy Rene has a 230v Lagoon 42 with Frigomar 10k unit. I mention 230v as it is more efficient both on the Multiplus and the Frigomar. On it's lowest setting (3K Btu/hr) it uses 450watts which includes the pump and the inverter losses.

Mabru, the lowest you can go is 3.5K btu/hr.
https://theyachtrigger.com/wp-conten...04/SC05-GN.pdf
Approximately 215 watts.

215w is significantly less than 450w all the while producing more cooling!


I already mentioned other advantages, no need for as much inverter capacity. Inverters aren't free, take up space, have to be wired and programmed and create heat. Heat when you are tying to have less heat. They also wear out faster when you use them harder.
The modern ones idle at 30-35w or more.

I was very hesitant about the Mabru. I wanted the Velair and Frigomar to be equally as efficient. I wanted to buy the Frigomar. After my research concluded, I ordered two Mabru 12K 12v.

Let us all know how you determined they are equal.

[poiu]

Originally Posted by FlyingScot

First, everyone may have a different situation. We don't have a built in generator, but if you do, the cost of the generator is way higher than just the price of the diesel to run it. Way way higher.
So let's say the losses are exactly same from the inverter or battery charger, which is a better time to be more efficient? I'd say when you don't have an abundance of power is the better time to use less power!

Your second point on cost. I agree that the Mabru costs more. But double? Show me where you can buy a Frigomar (not Frigoboat) variable speed inverter aircon for half. The Velair is the cheapest of the three.
I have had great experience with Andre@theyachtrigger.com. He has sold all three of brands and should be able to help give great advice.

I'll skip to your last point for a moment. Did you read what I wrote?
Here it is again "Velair/Frigomar have the advantage of being truly variable speed which should almost entirely eliminate cycling. The Mabru being soft start but then just two speeds." So on this point we agree.

Now let's talk efficiency: My research shows differently than yours. Would you like to show your research?

They both make 7K btu/hr units, so lets compare them:
https://www.frigomar.com/en/products...inverter-bldc/
Frigomar says it uses 470 watts on 120v to make 7K btu/hr.

Mabru states 28 amps @ 12v. Let's call it 12.5, so 350 watts.

Now which is actually more efficient?

But wait, there is more... The Mabru includes the seawater cooling pump in that number? How much does your seawater cooling pump use? I bet it is a lot! It can be upwards of 150-200w.

You already mentioned inverter losses, but let me give you a real world example by adding all of it together. My buddy Rene has a 230v Lagoon 42 with Frigomar 10k unit. I mention 230v as it is more efficient both on the Multiplus and the Frigomar. On it's lowest setting (3K Btu/hr) it uses 450watts which includes the pump and the inverter losses.

Mabru, the lowest you can go is 3.5K btu/hr.
https://theyachtrigger.com/wp-conten...04/SC05-GN.pdf
Approximately 215 watts.

215w is significantly less than 450w all the while producing more cooling!


I already mentioned other advantages, no need for as much inverter capacity. Inverters aren't free, take up space, have to be wired and programmed and create heat. Heat when you are tying to have less heat. They also wear out faster when you use them harder.
The modern ones idle at 30-35w or more.

I was very hesitant about the Mabru. I wanted the Velair and Frigomar to be equally as efficient. I wanted to buy the Frigomar. After my research concluded, I ordered two Mabru 12K 12v.

Let us all know how you determined they are equal.

My efficiency figures are from Velair’s spec sheets and my real world measurements, including from my pump they are better still. Details in my earlier posts.

I’m most interested in the all night low end consumption. My 10k Velair puts out about 3000btu at 240w measured inc pump.The Mabru 5000btu unit puts out 3500btu at 212w by the spec sheet plus pump. Close enough in my judgement to be considered equal. The Mabru doesn’t have the peak capacity, which is sometimes useful.

[FlyingScot]

Originally Posted by poiu

My efficiency figures are from Velair’s spec sheets and my real world measurements, including from my pump they are better still. Details in my earlier posts.

I’m most interested in the all night low end consumption. My 10k Velair puts out about 3000btu at 240w measured inc pump.The Mabru 5000btu unit puts out 3500btu at 212w by the spec sheet plus pump. Close enough in my judgement to be considered equal. The Mabru doesn’t have the peak capacity, which is sometimes useful.

I posted this: "From my research the 12VDC Mabru is the most efficient."

You posted: "The Mabru is actually equally efficient as the Velair and Frigoboat."

Then I went on and posted facts about the two units.

You responded that your system only uses 240w.

If you are getting 3K btu/hr from 240w and the Mabru does 3.5K btu/hr from 212w, then you are using 13% more power to achieve 17% less cooling.

Yours would likely need 280w to achieve 3.5K btu/hr. So apples to apples yours would use approximately 32% more power.

I think we can all agree that using almost 1/3 more power is not "equal" or even "about equal".

Even your 240w is suspect as the Velair specifications I read shows that it uses 240w in eco mode not including pump and inverter losses. So maybe you got an amazing one, or more likely it is putting out less cooling than 3K btu/hr.

On top of that, a few posts ago you let us all know: "Zero factory tech help and ignored emails" when you spoke about Velair.

Yes the Mabru costs more. But you will get support. It will be easy to install and run. No sourcing your own pump and constantly adjusting the pump for your cooling needs. Plus it will save 1/3 the power.

What does adding 1/3 more batteries and charging sources cost?

I stand by my assertion that the Mabru is the most efficient.