Air Heater on Hunter 38

[Sergey Vetrov]

Hello fellow Sailors! Just wondering is anybody has installed Air Heater on Hunter 38.
I am planning to buy WEBASTO Air Top EVO 40 for my yacht to "extend" sailing season through all year. If you have Air Heater already installed in your boat - few photos with heater positioning, ducting, etc. would be VERY helpful! Also I would like to know how noisy is it - my wife is very sensitive so I should take it in consideration. Thank you in advance

 

[jssailem]

Hello Sergey. You have a nice Boat. I do not have a Hunter but my 35Cal Cruiser is similar in size.. I installed a Wallas 40D on the boat last year. It is great.
Issues I experienced in the install:

• routing of heat ducts,
  
• Insulation for ducts,
  
• routing of fresh air and return air ducts,
  
• as well as location of heater.

The rational I used:

• Locate the unit as far from the living space as practical (noise from fan and burners not near the Salon or sleeping area),
  
• Ducts to Salon each side one near bow and one near stern (This is the space we are most likely to be using not covered by blankets, small dc fan can push warm air to V-Berth if needed - I like a cool sleeping space.),
  
• Insulate ducts in locker spaces with reflectwrap (when finished hot air temps from heating vents about 90F more than needed able to turn unit down to lower setting),
  
• Add a bend to return air duct in aft section of cabin (helped to reduce air and fan noise. Locating the return duct near the aft of the cabin space draws warm air to the aft section of the boat).
  
• Use fresh (outside) air as one of the cool side returns (helps to dry out the boat, outside cold air is less humid than inside air).
• Get a Y duct to be able to add additional outlets once you have made the install and get some experience on your boat. I have one ready to install in the head should I experience the need.

The result, Great heater, minimal noise - mostly blowing air which can be turned down as desired. Once the ducts were wrapped with insulation the temps in the boat were awesome. I can sit or work in the boat in a tee shirt while the outside temps are in the 20's F. Best of luck mate. It is a smart addition to your boat.

 

[Sergey Vetrov]

Hi John,
Thank you for prompt reply.
I can guess that Wallas 40D is the 4kW heater - similar to EVO 40.
At this stage I am thinking about cockpit locket for Heater positioning - it is far from main saloon, V-berth and hopefully far enough from master bed (insulated by locker walls and false ceiling...). However hot air ducting has to go be backwards to go in the aft area. From there I have to work out the way to get it to the middle on the boat...
Another option - somewhere under navigation seat - easy to manage hot air ducting to main area, front cabin and head...
Thank you for advise about ducting insulation. Great idea to deliver hot air where it should be delivered w/o wasting it...
Cheers
I have a friend who leaves on the boat with his wife all year around - they have heater installed and they absolutelly love it! Please note - winter in Auckland is very mild - 13-15 deg C during day time and down to 6-8 deg C at night but can be very wet so I like option to keep my boat dry
Thank you again
Sergey

 

[quadrille38]

My Hunter 38 came with air conditioning / heating system installed. Actually 2 systems. They Marine Air Systems unit made by Dometric.
The air ducts and vents are located in the ceiling of the main cabin. In the aft cabin the vent is in the aft facing wall of the hanging locker on the port side. And in the forward cabin it is in the bulkhead between the main cabin and forward cabin on the starboard side.

You might want to do some investigation because I understand that there were times when Hunter installed the duct work even though the boat wasn't ordered with the air/heat system. The idea was that it was easier and cheaper to do at construction. I've found a few other places where systems were roughed in making future installation possible. For example an emergency high water high volume bilge pump. All the hoses, wiring, etc. were put in.

The two compressor units were installed with one in the main cabin under the dining table settee. It's under the seat that is against the bulkhead shared with the forward cabin. The other unit is installed under the bed in the aft cabin. Surprisingly even though we sleep right on top of it, it not noisy enough to keep us awake.

The thermostats for the two systems are located with one on the port side of main cabin near the nav station. The other is in the aft cabin on the engine compartment wall right above the little vanity counter. I would not recommend this location though as the engine block heat can throw the readings off and cause the air conditioning to run forever or the heat to not run at all.

 

[Sergey Vetrov]

Thank you! This is what I am hoping to find with my Hunter - some existing ducking to hook my new Heater to.Will wait for more comments - I am sure somebody has done it already
And you are right Hunter boats comes with all harnesses to connect optional equipment. I was so pleased to find all wires and quadrant with connection pin when I installed Raymarine EVO Autopilot - it was nice and easy job! Also I found wires in the Aft Cabin in storage on port side - looks like they are there for AC unit as you mentioned.
Cheers
Sergey