After much debate, discussion, and work not only on my part, but the part of the techs over at North Harbor Diesel we finally have a fully operational heating system in our 4788.
The technology we chose was forced air with a fresh air component. We went with this because we wanted to have the furnace draw fresh air from outside the boat, heating and ventilating at the same time.
The brand of units we chose was Wallas. We went with Wallas primatially for two reasons. First, the Wallas units are dead quiet. Much quieter than any other furnace on the market. Another reason is that on most furnaces the furnace cycles on and off all night long. I actually timed it on our 2859 and about every 15 minutes in 45 degree weather outside the furnace would cycle back on.
The Wallas units have a thermostat that varies the BTU output of the unit between 1K btu on low and 10K btu on high, with several intermediate steps. This means that on a normal evening, the furnace will "figure out" the correct heat setting and keep the temperature constant.
The 4788 is a big boat with three living levels. Heating it is a challenge. We decided that all total we needed between 25 and 30K BTU to meet our goal of keeping the interior at 70 with a 25 degree outside air temp. Having too large of a furnace is almost as bad as too small. The challenge is to properly size the system so that the "low" output of the furnace will not create too much heat for the space on a semi warm day, and that the "high" output keeps the space at the desired temp on a very cold day.
We installed one 7K btu furnace behind the pilothouse dash. This furnace heats the pilothouse and provides defrost. Return air is pulled from both inside the pilothouse and outside for fresh air ventilation.
The salon is heated using a 10K btu furnace installed behind the setee. This has two vents on the setee, with fresh air being drawn from inside the cabin and from outside.
The staterooms are heated using a 10 kbtu furnace installed underneath the pilothouse setee. There are vents in each stateroom.
Here's a bunch of photos. I'll post photos of the stateroom heater when I round them up.
Attached files [img]/media/kunena/attachments/vb/644200=23411-pilothousedefrost.jpg[/img] [img]/media/kunena/attachments/vb/644200=23412-pilothousefurnace.jpg[/img] [img]/media/kunena/attachments/vb/644200=23413-pilothousethermostat.jpg[/img] [img]/media/kunena/attachments/vb/644200=23414-pilothousevents.jpg[/img]
The technology we chose was forced air with a fresh air component. We went with this because we wanted to have the furnace draw fresh air from outside the boat, heating and ventilating at the same time.
The brand of units we chose was Wallas. We went with Wallas primatially for two reasons. First, the Wallas units are dead quiet. Much quieter than any other furnace on the market. Another reason is that on most furnaces the furnace cycles on and off all night long. I actually timed it on our 2859 and about every 15 minutes in 45 degree weather outside the furnace would cycle back on.
The Wallas units have a thermostat that varies the BTU output of the unit between 1K btu on low and 10K btu on high, with several intermediate steps. This means that on a normal evening, the furnace will "figure out" the correct heat setting and keep the temperature constant.
The 4788 is a big boat with three living levels. Heating it is a challenge. We decided that all total we needed between 25 and 30K BTU to meet our goal of keeping the interior at 70 with a 25 degree outside air temp. Having too large of a furnace is almost as bad as too small. The challenge is to properly size the system so that the "low" output of the furnace will not create too much heat for the space on a semi warm day, and that the "high" output keeps the space at the desired temp on a very cold day.
We installed one 7K btu furnace behind the pilothouse dash. This furnace heats the pilothouse and provides defrost. Return air is pulled from both inside the pilothouse and outside for fresh air ventilation.
The salon is heated using a 10K btu furnace installed behind the setee. This has two vents on the setee, with fresh air being drawn from inside the cabin and from outside.
The staterooms are heated using a 10 kbtu furnace installed underneath the pilothouse setee. There are vents in each stateroom.
Here's a bunch of photos. I'll post photos of the stateroom heater when I round them up.
Attached files [img]/media/kunena/attachments/vb/644200=23411-pilothousedefrost.jpg[/img] [img]/media/kunena/attachments/vb/644200=23412-pilothousefurnace.jpg[/img] [img]/media/kunena/attachments/vb/644200=23413-pilothousethermostat.jpg[/img] [img]/media/kunena/attachments/vb/644200=23414-pilothousevents.jpg[/img]
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