H340 Factory AC System - Am I lucky or not?

[markymac1961]

So my recently acquired 1999 H340 has an original factory installed AC unit (I think these were an optional extra).
Although I'm sure I may love it on hot sweaty nights, (North Queensland - OZ) I can't help noticing how 'in your face' the whole system is.

The AC unit itself takes up a huge amount of under berth storage space on the stb side, and this appears to extend to an under bench timber 'box' that prevents me sitting at the nav station (nowhere for my stumpy little legs to swing).
There's what appears to be unnecessarily large 5-6" ducting snaking through almost every cupboard and locker throughout the boat. And to power it offshore, the prev owner has jammed a large portable diesel generator in the STB aft transom locker... filling it completely.

So folks... my questions are as follows:
1. Has anyone 'moved' the AC unit to a more suitable/compact space.
2. Does the ducting throughout the boat need to be such a large diameter?
3. Is there a potential operational and/or efficiency problem with any or all of the above?
4. Has anyone ripped the whole system out, sold it... and just 'sweated it out'?
Any other tips and experiences would be most welcome.
Absolutely LOVE the boat, not so sure about the AC system.

Cheers and TIA - Mark Mac

 

[colemj]

We don't own your model boat, so I can't answer the boat-specific stuff. However, the general question on duct size is easy. Every A/C unit requires a certain minimum outlet area. This will be dependent on A/C size (btu) and fan speed, and should be in the installation manual. Yours may be sized correctly, or may be larger than needed because it goes to several outlets that together exceed this minimum.

Moving a unit usually does not affect the efficiency much, although if it was moved a long way away from where you want the coolest air, it might have some efficiency decrease for that spot.

There are newer A/C units that are more compact than older ones. There are also variable speed units that are more efficient than older ones.

Mark

 

[DRhoads]

Don't forget about the cooling requirements. It requires X amount of space to be able to draw air and keep from overheating.

 

[Johann]

We had the H336 (nearly identical to the H340) and I share your feelings about the AC installation. Before we decided to sell the boat my plan was to remove the ducting that goes aft from the unit and install a small high efficiency AC at the foot of the aft berth to cool the aft berth and head. Then convert to LiFePO4 batteries and a high output alternator for use off grid.

 

[jssailem]

MarkMac... I think Lucky!
You "recently acquired a 1999 H340".
AC is a compromise. You either need to stay in a Marina so you can keep it plugged in and running, or you need a generator running to keep the AC running, which will make you the noisiest boat in the anchorage.

Better to wear fewer clothes, have a sunshade with a "tinny", and an occasional dip in the water.

 

[colemj]

AC is a compromise. You either need to stay in a Marina so you can keep it plugged in and running, or you need a generator running to keep the AC running, which will make you the noisiest boat in the anchorage.

This isn't necessarily true anymore. The new variable capacity units are more energy efficient, as are new solar and battery technology. We run our A/C in our stateroom every night, and it uses 100-120Ah doing so. This doesn't bother the lithium batteries at all, and the solar has that back under an hour. Of course, the battery and solar capacity is relative among different boats, but that A/C consumption is absolute.

So if one can accommodate the 120Ah overnight, and can restore that amount by some charging source during the day, then no marina or generator necessary.

Mark

 

[jssailem]

I must agree you have solved one of the challenges of living in the tropics. While we get adequate sunlight in the summer to deliver a solar charge to the batteries, the winter and shoulder seasons are a bit dark for the demand. Then it is not AC we need it is heat.

 

[markymac1961]

We don't own your model boat, so I can't answer the boat-specific stuff. However, the general question on duct size is easy. Every A/C unit requires a certain minimum outlet area. This will be dependent on A/C size (btu) and fan speed, and should be in the installation manual. Yours may be sized correctly, or may be larger than needed because it goes to several outlets that together exceed this minimum.

Moving a unit usually does not affect the efficiency much, although if it was moved a long way away from where you want the coolest air, it might have some efficiency decrease for that spot.

There are newer A/C units that are more compact than older ones. There are also variable speed units that are more efficient than older ones.

Mark

Great answer mate makes absolute sense. I might get the Marine AC guys down for a look and see what they suggest. All the best cheers.

 

[markymac1961]

Don't forget about the cooling requirements. It requires X amount of space to be able to draw air and keep from overheating.

Yes mate that what I was thinking too. I know nuffink about how these systems work... except magically turning hot in to cold. I think I'll get the Pros in and see what they suggest. All the best - Mark Mac