What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Electric Seat Heat

Berchmans

Well Known Member
I am planning on installing electric seat heat in both seats of the RV8 I am building. I am using the heating elements sold by flyboys. I am currently thinking of installing the seat operating switch in the right side arm rests of the front and rear positions. I am also thinking of putting individual push,pull beakers in each arm rest for the switch ahead of the heater control. My question to the group is what have you done for both the control switch and the breakers? The elements came with inline auto style fuses but I don't think I am going to use those. Photos would be greatly appreciated...
 
In the 7A, I could not find a good place for the Hi-Off-Low switch without rebuilding the entire wire harness. I switched it to HI and stuck it under the seat pan to never be operated again. I ditched the fuse and installed a on-off breaker switch on the panel. The wife is extremely happy. I seldom ever turn it on.
 
I ran the factory inline fuse, and another fuse in a fuse block installed as a sub-panel distribution center for cockpit accessories. Two red wires upper left.

P5110057.jpg


The heat in the pilot seat is out, and I will be replacing the fuse now during my "annual". I will also be deleting the factory inline fuse, as it is too hard to get to, inside my tunnel.

I have to remove the seats to get the top off of the tunnel, lots of work just to replace a fuse.
 
Seat Heat

I installed the Flyboys seat heat in the rear seat only.

I mounted all seat heat components inside the removable side panel under the right armrest, including the hi-lo-off switch (about 2" aft of the leading edge of this panel). Wiring, relay, etc. were mounted with adel clamps. I used stainless screws (for appearance) since the screw heads are visible inside the cockpit.

The connectors to the seatback and bottom cushion exit the panel through a rubber grommet under the right seat belt attach bracket.

I connected tefzel wire from the main bus to the kit harness inside this same panel, so only a few inches of the original kit power supply harness were used. Power and ground wires were routed through the floor using a rubber grommet in the space enclosed by the side panel.

There's plenty of room behind this side panel; I also mounted a TCW Safety Trim module there.

Good luck,
Mike
 
Something to think about

When I was building, I thought about putting these in my RV but some member of this forum posted that his Volvo had just caught fire due to a short in the seat heaters and that he almost didn't get stopped in time.

While I like the thought of seat heaters, I don't like the thought of a possible in flight fire.

Just something to think about.
 
his Volvo had just caught fire due to a short in the seat heaters

Why didn't his circuit breaker or fuse catch the short? It sounds like there were extenuating circumstances in the Volvo.
 
Can anyone running electric seat heaters post the current consumption please. Also do you have any control on the amount of heat being produced? Thanks in advance.
 
I love my heated seat, it keeps my wife very warm and we hardly ever need to use our heater from engine.

I have installed a circuit breaker for the main power and have two inline fuse for each of the seats. The on/off switches are installed between the seats and have two settings low/high.


IMGP6610 by bavafa1, on Flickr
 
Looks from Mehrdad's switch pictures that we out the same device in our new RV-3. I can check the current consumption next week when we are in the hangar, but if I recall correctly, it's somewhere between three and five amps.

I have used the heater sitting in the hangar on a cool Houston day (40 degrees) setting up avionics (with external power on the airplane), and it is quite toasty!
 
Wish I would have

I didn't put in the seat heat and after flying on a couple of days with OAT around 20F I regret not doing it!
 
Looks from Mehrdad's switch pictures that we out the same device in our new RV-3. I can check the current consumption next week when we are in the hangar, but if I recall correctly, it's somewhere between three and five amps.

I have used the heater sitting in the hangar on a cool Houston day (40 degrees) setting up avionics (with external power on the airplane), and it is quite toasty!

Hey Paul, Thanks for the speedy reply. That's about 36 to to 60 watts. I would have thought the current consumption would be more but on further contemplation, it sounds about right. I must think about installing seat heaters in my 4 as that current consumption is acceptable and I would not need to go to a big alternator to drive them.
 
Thanks for all the input...there is no way my wife would be happy with anything less than a warm seat. I have seat heat in my truck and she loves it. Some great ideas on how to run it. Up here OAT's of zero or below are fairly common in the winter as you can guess...if the wifes not happy, no one is happy...
 
Looks from Mehrdad's switch pictures that we out the same device in our new RV-3. I can check the current consumption next week when we are in the hangar, but if I recall correctly, it's somewhere between three and five amps.

I have used the heater sitting in the hangar on a cool Houston day (40 degrees) setting up avionics (with external power on the airplane), and it is quite toasty!

Paul,
If I am not mistaking, it is 3A on low setting and 5A on high settings. The low settings is usually enough even for my wife but we don?t live or fly in super cold environments.

Happy holidays to every one
 
RV-8A Seat Heaters

My question to the group is what have you done for both the control switch and the breakers? ... Photos would be greatly appreciated...

No breakers in my installation -- I wired each seat to its own 7.5A fuse on the Master Bus. After tracing out the schematic, I discarded nearly all the PVC-insulated wiring and rewired it with Tefzel aircraft wire of appropriate lengths. For the included relay I discarded its plastic socket and used 1/4" Faston terminals to connect to it. The switch required 3/16" Fastons. When finished the installation was a good deal lighter and cleaner. I can save you some work: email me if you'd like a schematic diagram.

For the forward seat, I mounted the Hi-OFF-Lo switch and relay in the upper right console (along with my lighting controls).

FwdSeatHeaterControl.jpg


I did something similar for the aft seat on the right side of the fuselage.

AftSeatHeaterControl.jpg


Here you can see the switch and relay wiring which are hidden by covers in my installation.

I ordered these seat heaters direct from the manufacturer and am very pleased with them. Each pair of heater elements (one seat) draws no more than 5A in "Hi" (both elements in parallel) and about half that in "Lo" (both elements in series). I've been using one in my Long-EZ for a couple of years now and wonder how I ever managed without it.
 
I ordered these seat heaters direct from the manufacturer and am very pleased with them.

Aw, Joe.... yer killing me. I buy from him in bulk and his price is still slightly higher than mine! Only $0.05, but I'm here all the time!

BTW, these seat heaters are rated at 6 amps per seat on HIGH. Someone asked earlier.

Support your friendly RV vendors! (So we can avgas!)

Thanks,
Vince
 
... Support your friendly RV vendors! (So we can avgas!) ...

That must be the "royal we", Vince, as opposed to "you" and "me" because I don't see how I "can avgas" on the purchase.

The factory offered me a good deal on shipping and delivered promptly. That said, I did buy a seat heater from you (for my Long-EZ) a while back.

--
Joe
 
NEVER trust the advertising department!

Hey Paul, Thanks for the speedy reply. That's about 36 to to 60 watts. I would have thought the current consumption would be more but on further contemplation, it sounds about right. I must think about installing seat heaters in my 4 as that current consumption is acceptable and I would not need to go to a big alternator to drive them.

Tony,
If you REALLY need more than 45 amps, the small [30 to 60 amp rated, including the PP unit] ND alternators are not the way to go. Due to limited available space, the rectifier diodes are not up to supplying over 45 amps for more than a few seconds time. They will overheat and fail. For those who are electrically challenged, the 6 diodes in the rear of the alternator form a "bridge" rectifier. This rectifier converts the AC current to a useable DC current. Each failed diode will decrease power output by 1/6th of rated power. The diodes in the "small" 60 amp ND alternator are the same size as those in the 30 amp model. See

http://www.vansairforce.com/community/showthread.php?t=49142&highlight=Nippon+Denso+alternator

Charlie
 
No breakers in my installation -- I wired each seat to its own 7.5A fuse on the Master Bus. After tracing out the schematic, I discarded nearly all the PVC-insulated wiring and rewired it with Tefzel aircraft wire of appropriate lengths. For the included relay I discarded its plastic socket and used 1/4" Faston terminals to connect to it...

I did the same thing on my RV-7, except I also discarded the relays supplied and used the same ones (B&C P/N S704-1 / Potter & Brumsfield P/N T9AP5D52-12) I used for the rest of the electrical system (Standby Alternator, EBUS Aux Feed, Brownout relay, etc.). That way, if one of the more critical relays fails, I can always use one of the seat heat relays as a spare to replace the more critical relay to get me home.:rolleyes: By the way, I used 10A fuses on the Main Bus (Aeroelectric Z10-8 architecture) and AWG 18 gauge wire.

Here's a schematic of my seat heat system:
SeatHeat.jpg


Edit: Oh, and I also added a spike suppression diode (1N4001) across the coil of each of the relays to help increase the longevity of the seat heat switches (the original harness did not include these, and they're not totally necessary, but I would recommend adding them).
 
Last edited:
... Here's a schematic of my seat heat system: ...

Nicely done, Paul. But then, I wouldn't have expected anything less from a Sparky (E.E.) <g>.

That P&B T9AP5D52-12 relay is inexpensive and an excellent part.

--
Joe
 
Last edited:
Tony,
If you REALLY need more than 45 amps, the small [30 to 60 amp rated, including the PP unit] ND alternators are not the way to go. Due to limited available space, the rectifier diodes are not up to supplying over 45 amps for more than a few seconds time. They will overheat and fail. For those who are electrically challenged, the 6 diodes in the rear of the alternator form a "bridge" rectifier. This rectifier converts the AC current to a useable DC current. Each failed diode will decrease power output by 1/6th of rated power. The diodes in the "small" 60 amp ND alternator are the same size as those in the 30 amp model. See

http://www.vansairforce.com/community/showthread.php?t=49142&highlight=Nippon+Denso+alternator

Charlie

Hi Charlie,

Jury is out at the moment as to which supplier I go for but I have had good experience in the past with B & C when I replaced the generator on my SuperCub with a 40amp certified alternator. Had to go certified as my Cub was registered for aerial work with it's banner and glider towing hook. I will be looking at the B & C 60amp alternator but I will be keeping a close eye on weight which is the more important factor for me. I want this 4 to be as light as possible but to include some creature comforts for trips back to the UK.
 
Last edited:
I'm digging up this old thread because it's the closest answer I've found for my current issue.

I have the FlyBoys heating pads that are yet to be installed in the seats. I have the front seat figured out, but I'm still undecided about the rear seat. I'm considering a few different switch locations and how I'll route wires from the heating elements to the relay, switch, fuse block, etc. but so far I haven't come up with an ideal solution. I want to be able to remove the rear seat easily (or at least the cushions) for luggage loading flexibility, so I don't want to bury the quick disconnect somewhere that's difficult to reach or reconnect.

Does anyone have RV-8 rear seat electric heaters that you could post send me a few photos of how you ran your wires? Seeing a few different solutions would really help me figure this out.

Any insight would be helpful.

Thanks!
 
fire?

If your seat is on fire, and you have not turned it off.... you get a D minus for situational awareness.
I run the heat on my wife's seat. On low, it is perfect. I eliminated the OEM relay and went better quality. I am warm blooded and don't bother with the heat.
 
Seat heater

Does anyone use the portable seat heater that you plug into a cigarette ligbter? I have one but haven't used it as I wasn't sure how good of an idea. The colder winter has made me think more about keeping warm.

Thanks.
John
RV-8
 
I've been running a pair of the cheap portable ones in my "other" airplane for quite a few years now. A single cigarette lighter socket in the panel was not going to cut it so I found an aftermarket extender/splitter that has a male cigarette lighter plug on one end and a triple female socket on the other end and about six feet of wire in between. Perfect for plugging the seat heaters in with all the cords etc being behind the seats and out of harm's way.
 
Up front.....

Classic Aero made my seats with heat and Stein incorporated the switches in the upper left of my panel. I used the factory wiring harness "as is" with all the plug in stuff accessible behind the panel thru the baggage compartment mod. I extended the wires to each seat with the other wire runs. I'm about to install the floors permanently and I'm thinking I will terminate with a molex plug that lays underneath/behind/beside each seat.
 
Last edited:
Does anyone use the portable seat heater that you plug into a cigarette ligbter? I have one but haven't used it as I wasn't sure how good of an idea. The colder winter has made me think more about keeping warm.

Thanks.
John
RV-8

I do. Got ?em off of Amazon. They do a good job keeping us warm, so I took out the sketchy (IMO) heat muff and have gone ?all in? with the portable seat heaters along with heated vests/gloves/socks, etc.

Lots of very good battery powered stuff out there now, especially for motorcyclists. Effective and relatively long life.

The bennies (to me) of going my route is that I don?t have all the wiring issues that come with a built-in seat heater, I can take it out in the summer (weight savings) and I?m also saving the 1 pound or so of weight from the heat muff (as well as avoiding the CO issue.)

The 12V adapter for the seat heaters is useful for other stuff when I?m not using it for those.

For us below-the-Mason-Dixon types who rarely venture north in winter, it?s a completely workable solution.
 
Blake offers 2 types of seat heaters. The orange ones have a nylon outer shell which makes them waterproof and more resistant to damage, ie if you're stepping in the seat.

More info in the listing.

Seat heaters
 
I also use portable seat heaters like Aggie78 and it works quite well in Ohio, especially for the back seater in my RV8. The 12V adapter (cigarette lighter socket) is protected by a 5 amp circuit breaker and I?ve never had a trip, so it must be using less than 5 amps.
 
I'm digging up this old thread because it's the closest answer I've found for my current issue.

I have the FlyBoys heating pads that are yet to be installed in the seats. I have the front seat figured out, but I'm still undecided about the rear seat. I'm considering a few different switch locations and how I'll route wires from the heating elements to the relay, switch, fuse block, etc. but so far I haven't come up with an ideal solution. I want to be able to remove the rear seat easily (or at least the cushions) for luggage loading flexibility, so I don't want to bury the quick disconnect somewhere that's difficult to reach or reconnect.

Does anyone have RV-8 rear seat electric heaters that you could post send me a few photos of how you ran your wires? Seeing a few different solutions would really help me figure this out.

Any insight would be helpful.

Thanks!

Hey Rob, here's how I wired mine up. Placed the relay under the floorboards and installed the control switch on the right side panel. Connections to the seat heaters are finished off with a couple of Molex connectors that end up under the rear seat cushions (one for the bottom seat heater and the other for the back seat heater). I mailed the seat heater pads to Abby at FlightLine Interiors and she installed them into the seats. No issues whatsoever unplugging the connectors and removing the seat cushions. I do that during the annual condition inspection for easy access to the back. I do not have to remove any cushions when placing items in the rear baggage compartment. I do have a removable floor so if you rivet yours down this may not work for you. Hope this helps.

2qwn679.jpg


10r8om0.jpg


bj8prl.jpg
 
Karl,

Thanks for the info. What are the other three items on that panel? Two of them look like single plug headset jacks, what's the bigger one aft of the seat heat switch?

Do your pad wires just come up under the stick cover console, or is there a hole in the floor for the wires? I was wondering if there would be an issue with running wires under the seat cushion. I could cut a little relief in the foam to create a channel for them to route under, but I wasn't sure if that was necessary.

Looks like you retained all the OEM wiring, is that right? My power wires won't reach the fuse block up front, so I'll probably replace those, but I'm undecided on replacing the others or not.

Thanks!
Rob
 
The two additional plugs are LEMO plugs for the Bose A20 headsets. Ships power for the headsets with batteries as a backup. I need to move the rear headset plug to the fuselage rib to prevent any rear seat passengers from accidentally damaging the plug when they slide their right foot into the footwell. Just haven't gotten around to doing that.

The large plug is a power plug for iPad in flight entertainment. It's a higher quality motorcycle power plug that comes with a dust cover. I put one in the forward cockpit too, next to the seat heat control, fire extinguisher and canopy breaker tool.

http://www.bikerhiway.com/product/cigarette-socket-panel-mount-kit-48/

I did retain most of the original wiring harness for the seat heaters. Like you mentioned, the power and ground wires will not reach the fuse panel so I replaced those. I have a separate fuse for each seat heater set.

Pad wires come up under the stick cover. I cut a small relief channel for the wires. No modification was made to the bottom seat cushions.
 
Last edited:
If your seat is on fire, and you have not turned it off.... you get a D minus for situational awareness. ...
You are assuming the fire goes out when the power is cut.

I would want to do a flame test on an extra set of seat cushions and the seat covering.

Not to mention any noxious fumes that may come from the electrical components / wires.

I get it, like you my wife does not put up with the cold. To solve this, I had some removable wool seat covers made. They work great in the summer or winter.
 
I get it, like you my wife does not put up with the cold. To solve this, I had some removable wool seat covers made. They work great in the summer or winter.

I guess I never realized how lucky I am. Mine came from Minnesnowda and lives in Texas. She just puts on more layers. "Don't need all that stuff that would burn more fuel."
 
Thanks Karl!

The two additional plugs are LEMO plugs for the Bose A20 headsets. Ships power for the headsets with batteries as a backup. I need to move the rear headset plug to the fuselage rib to prevent any rear seat passengers from accidentally damaging the plug when they slide their right foot into the footwell. Just haven't gotten around to doing that.

The large plug is a power plug for iPad in flight entertainment. It's a higher quality motorcycle power plug that comes with a dust cover. I put one in the forward cockpit too, next to the seat heat control, fire extinguisher and canopy breaker tool.

http://www.bikerhiway.com/product/cigarette-socket-panel-mount-kit-48/

I did retain most of the original wiring harness for the seat heaters. Like you mentioned, the power and ground wires will not reach the fuse panel so I replaced those. I have a separate fuse for each seat heater set.

Pad wires come up under the stick cover. I cut a small relief channel for the wires. No modification was made to the bottom seat cushions.
 
Back
Top