Thread: Heated boat seats

Originally Posted by theygotaeat

I have a set of heated seats from a wrecked vehicle I'm thinking about fabbing up a mount and putting them in my boat any thoughts opinions or has anyone done this before?

I have heard of "freezing your ass off" but it's rarely the coldest part of me. I guess lard is warming.

Originally Posted by LIFRANK

First you have to check the resistance of the heating element in the seat. Then using ohms law you
can calculate the Current(I) drawn if the seat is powered by 12Volts. Once you know the current then
you can go on to calculate the power, for example if the resistance(R) of the seat is 100 ohms and is powered
by a 12 volts battery then the current would be Current I = (V/R ) = 12/100 = 0.12 Amps or 120 milli Amps.
the power drawn would be Power P = (Current^Current*Resistance) = 0.12*0.12*100 = 1.44 Watts. Now lets look at
how this would affect your battery on your boat, if you have a 120 Ampere an Hour (AH) using the example above
it would take (120/0.12 )= 1000 hours to drain your battery, If you fish 8 hours per day your battery would last for (1000/8) = 125 days providing that the seat is the only device connected to the battery. NOTE:This example is only based
on a seat heating element resistance of 100 ohms @12VDC, If the resistance is less the current drawn will increase along with the power drawn and that would definitely affect your battery drain time.You must check the resistance of the heating element then do the calculation.

Lifrank.

Very good, I like that. Thank you. For any decent heat generation 100 ohms resistance won't cut it.

I would have to check to be sure but its not going to be mili-amps on those heated car seats....its going to be amps and I think they are on a dedicated circuit in my truck with a 20 amp fuse.....so....they will use a good bit of battery ( it works in the truck because it has a 155 amp alternator).....then factor in the other items that you would already have on the battery in your boat. I have three batterys in my boat...one for starting and operating the outboard and two fish finders, plus the live well, tilt and trim, bildge pump, air pump etc. everything in the boat except the trolling motor.....then two big group 31 batterys for the trolling motor only.....trolling with a 80 pound thrust Terrova at 1.8 mph takes a lot of battery.

Originally Posted by "G"

I would have to check to be sure but its not going to be mili-amps on those heated car seats....its going to be amps and I think they are on a dedicated circuit in my truck with a 20 amp fuse.....so....they will use a good bit of battery ( it works in the truck because it has a 155 amp alternator).....then factor in the other items that you would already have on the battery in your boat. I have three batterys in my boat...one for starting and operating the outboard and two fish finders, plus the live well, tilt and trim, bildge pump, air pump etc. everything in the boat except the trolling motor.....then two big group 31 batterys for the trolling motor only.....trolling with a 80 pound thrust Terrova at 1.8 mph takes a lot of battery.

G,
Of course it wouldn't be milli amps, i was just giving an example as an Electronic Engineer to illustrate how to calculate
Current and Power when the Resistance and operating Voltage are known.

Hey TGE,

I say give it a shot and report back.

My chevy truck seat heater uses a 20 amp fuse to protect the circuit. Rule of thumb is normal current flow would be half of the fuse size or 10 amp flow.

But the chevy system threw a module will pulse-width (10%-90%) the voltage depending on temp. This is how the late model vesicles can use electricity on more and more system (steering, Climate control,etc.) with out having to go to higher voltages.

I think you'ed be better of with a electric blanket if you can get out of the house with out getting caught.

On most vehicle elect systems the control switch is used to pull in a Relay that will handle the larger current without running heavy wiring all over the place to help reduce vehicle weight

On second thought you did not mention much about the seating you have. If it is Stick stearing, usually the seats are uncomfortable compared to a car seat, the metal cross piece the seats are mounted to are filled with some flotation but could be cut open to house a battery . With stick stearing I would go for it

Originally Posted by Fish on Line

On most vehicle elect systems the control switch is used to pull in a Relay that will handle the larger current without running heavy wiring all over the place to help reduce vehicle weight

Which vehicle would this be?

This is on a 2005 Chev. Pickup. Which they done this why for 15 plus years.

Factory Info Used for education purposes Only.

no relays involved.

Heated Seats Description and Operation

Heated Seat Components

The heated seat system consists of the following components:

Driver and passenger heated seat switches
Driver and passenger seat back heater elements
Driver and passenger seat cushion heater elements
Driver and passenger seat back temperature sensors
Driver seat module
Driver door module
Passenger door module
Heated Seat System Operation

The driver and passenger heated seats have 2 heat zone operating modes with 3 heat level modes and will operate only while the engine is running. The heat zones are determined by which of the 2 heated seat buttons are pressed, while the heat level is determined by the number of times they are pressed. Pressing the seat cushion button 1 time will activate the seat back and cushion heater elements in the high mode. Each time the seat cushion button is pressed the seat back and cushion heat level is reduced from high to medium, low, and off. Pressing the heated seat back button 1 time will activate only the seat back heater element in the high mode. Each time the seat back button is pressed the seat back heat level is reduced from high to medium, low, and off. During heated seat operation the heat zone operating mode may be changed without affecting the current heat level mode.

The heated seat switches are momentary contact switches and are inputs to the driver and passenger door modules. Battery voltage is supplied to the switch assembly from the door module, and when a heated seat switch is pressed and released a brief switch signal voltage is supplied to the door module. Whenever the door module receives an active heated seat switch input, the next heated seat operating mode is determined by whatever the current mode may be. The seat heater elements are controlled by the driver seat module using inputs from the door modules through Class 2 serial data circuit messages. The driver seat module controls the voltage supply and the ground circuits to the seat heater elements. When a heated seat function is commanded active, the seat module will switch battery voltage to the heater element supply circuits, and ground is provided through low side drive control circuits. During heated seat operation both the seat back and cushion heater elements are supplied battery voltage. The seat module grounds the appropriate control circuits for back only or back and cushion heating modes, and opens or closes the active control circuits as necessary in order to maintain the desired seat temperature. The seat module relies on inputs from thermistors located in the driver and passenger seat backs to control heated seat temperatures. The thermistors are 2 wire sensors supplied with a 5-volt referenced signal circuit and a low reference circuit from the seat module. Resistance through the thermistors varies with temperature causing the heated seat sensor signal circuit voltage levels to decrease as the seat back temperatures rise. The seat modules allow heated seat operation only while the engine is running which is determined by a Class 2 serial data circuit message from the powertrain control module.

2002 Ford Pickup Again no relays involved.