1. Measure the area to be cooled. (Measure the length, width and the average cabin height in the area.)
2. Using these three dimensions, calculate the cubic footage of the area. (Multiply the length times the width times the average cabin height. This is the area's cubic footage.)
3. Multiply the resulting cubic footage by a BTU factor as follows:

a. For below deck areas, multiply the cubic feet by 14.
b. For topside or salon areas, multiply the cubic feet by 17.

The resulting number will show the minimum BTU's needed for each area measured.

EXAMPLE CALCULATION
Assume you want to air condition three different areas on your boat indicated on the diagram below:

Area A Area B Area C Length 7' 10' 10' Width 7' 10' 10' Avg. Height 6' 7' 6'

Calculate the cubic footage:
Area A : (7' x 7' x 6' = 294) Area B: (10' x 10' x T = 700) Area C: (10' x 10' x 6'= 600)
Then, calculate the minimum BTU's needed for each area:

Area A and B combined require a total of 16,016 BTU, and can be served by one 17,000 BTU model. Area C requires 8,400 BTU and can be served by one 10,000 BTU model.
Note: These are general guidelines - other factors such as windows, insulation, curtains etc may affect these calculations.
 
WHERE'S THE BEST LOCATION FOR AN AIR CONDITIONER ON MY BOAT?
 
AIR CONDITIONING UNIT
Westerbeke/Rotary Aire Marine Climate Control units are quite compact, and will tit in any one of several locations on a typical boat. Usual locations would be in a closet, under a berth, a helm station or a dinette seat. The major consideration in selecting the best location is to make sure the space is large enough to accommodate the ducting.
DO NOT install a self-contained air conditioner in the engine room or an area where fuel vapors may be present. Your local Westerbeke / Rotary Aire dealer would be pleased to make specific recommendations for your boat.
 
WATER PUMP
The optimum location for the water pump is below the waterline. We recommend that a self-priming pump be used in a sailboat due to heeling. A self-priming pump should also be used in any boat if the pump cannot be installed below the waterline.
 
THERMOSTAT CONTROLS
Digital control is standard. It provides complete system control and monitoring from a four-button keypad and digital display.
In areas where moisture is a chronic problem, you may set the control in a "HUMIDITY MODE" and the air conditioning unit will automatically dehumidify the area, drawing up to several quarts of moisture out of the atmosphere hourly.
The digital control automatically monitors air temperature, water temperature, line voltage, compressor current and fan speed. Operational failure modes are visually indicated by the service light on the panel. There is also special time-delay circuitry to prevent nuisance tripping of circuit breakers when cooling or heating cycles are reversed too quickly.
 
WESTERBEKE RELIABILITY
Each Westerbeke/Rotary Aire Marine Climate Control System is manufactured by Westerbeke in its own factory to the company's own stringent marine standards. Units are designed to be as trouble-free as possible in the marine environment. Each unit is backed by a TWO-YEAR warranty, and supported by our worldwide distributor network for optimum customer support. Westerbeke has an established reputation for building world class marine products for over 60 years.