Espar Sizing 2

Diesel Heating -- Determining Type and Size
Hydronic (Hot Water) Water is heated by the diesel fired burner system and circulated through a closed loop of tubing or hoses to the area requiring heat. *In the area to be heated you can install convection type radiators or the most common installation is the fan forced radiator system similar to the heating system in your car. The fans on each heat exchanger can be controlled with a room thermostat to give you automatic zone controlled heating or with manual fan speed control switch. These units can also be installed with special heat exchanger units to heat domestic hot water for showers or the galley. Another option is to install a water to water heat exchanger between the main engine and the heating loop. This arrangement can allow the boat to be heated by the main engine when underway. Using the Boat Electric designed control system the operation is totally automatic. When the engine cooling system has excess heat available it will provide heat and the Espar unit will go to standby. Other systems may take too much heat away from the engine, this could result in less efficient operation. To see more information on specific Espar models, just click on the model number**
Model	Btu output	Amp Draw 12v (includes pump except where noted)	Maximum Boat Length Approximate
			POWER	SAIL
Hydronic 4	13,700 Boost 11,300 High 5,500 Low	3.3 Boost 2.9 High 1.5 Low	27	32
Hydronic 5	17,000 High 8,200 Low	4.4 High 1.9 Low	30	40
Hydronic 10	32,400 Boost 25,600 High 10,900 Medium 5,100 Low	4.5 Boost 2.4 High 1.4 Medium 1.2 Low	44	50
Hydronic 12	41,000 Boost 33,000 High 17000 Med1 11000 Med2 5100 Med3 4100 Low	8.4 amps (Boost) 6.6 amps (High) 3.5 amps (Med1) 3.0 amps (Med2) 2.6 amps (Med3) 2.4 amp (Low)	48	55
Hydronic 30	102,000	3.95 (24V Only)**	50	80
Hydronic 35	120,000	5.0**(24V Only)	72	90
Note: B = Boost Output (intermittent rating) H = High Output (continuous rating) M = Medium Output (when maximum is too much & low is not enough) L = Low (Minimum Output) * Convection type radiators are large and are not practical on most boat installations ** Heater only + Pump Current
Forced Air Air is heated by the diesel fired burner system and carried via high temperature flexible ducting to the areas requiring heat. The distribution of heat is controlled by using various duct sizes and in some areas adjustable heat registers may be useable to regulate hot air flow. The forced air systems utilize one centrally located thermostat to control the operation of the heater, very similar to a forced air system in a home.
Model	Btu output rating	Amp Draw 12v	Approximate Boat Size in Feet in the Northwest
			POWER	SAIL
Airtronic 2	7,500 Boost 6,150 High 4,100 Medium 2,900 Low	2.8 Boost 1.9 High 1.0 Medium 0.7 Low	24	30
Airtronic 4	13,650 Maximum 10,200 High 6,800 Medium 3,400 Low	3.3 Boost 2.0 High 1.1 Medium 0.6 Low	27	36
Airtronic 5	18,800 Boost 16,400 High 9,200 Medium 4,100 Low	6.7 Boost 6.7 High 3.3 Medium 3.3 Low	35	40
D8LC	27,300	9.6	40	50
Note: Boost = Intermittent rating. High = continuous rating Medium = when maximum is too much & low is not enough Low = Lowest Output (If the temperature continues to increase at low the heater will cycle off to standby.) (All hot air models turn off when no heat is required to maintain cabin temperature)

Sizing Guide for your application
Method 1
Cubic Foot Area to be heated - Measure the boat interior and use the guide below to determine your multiplier. Caution - when using this method of estimating the heat requirements, it is important to Accurately measure the INTERIOR VOLUME to be heated. Do not measure the box that the boat came in. Do not measure the space taken up by cabinets, bunks or other permanent structure.
Geographic Location	Limited Winter Use btu's per cubic foot	Winter Cruising btu's per cubic foot	Live Aboard All Year btu's per cubic foot
Southern California	7	8	9
Northern California	9	10	11
Oregon & Washington	11	12	13
South East Alaska	14	15	16
Alaska	19	20	21
Example: cubic foot area to be heated = 1000 Live aboard in Washington = 11 Estimated btu's: 1,000 x 11 = 11,000 - Heater size = Airtronic D4 hot air or Hydronic 4
This link will take you to a side by side explanation of the different version choices or click on the specific links below Espar Grand Mariner Heaters Espar Mariner Heaters CAN I INSTALL IT MYSELF? Yes!! Boat Electric has configured Espar's universal models for easy marine installation. With the simplified instructions installation is easier then ever, requiring only basic mechanical skills. If you have a question your local dealer is just a phone call away. West Coast Espar Dealer List *Specific installation instructions are not currently provided on our web site.*
e-mail us with your requirements (using the sizing guides) and we can furnish you with current pricing for your heating system requirements. West Coast Espar Marine Dealer List
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