How to connect AC wire in the engine compartment

mrsrobinson

Well-Known Member
Mar 9, 2006
7,704
Virginia
Boat Info
2001 380DA
Engines
Caterpillar 3126
So lots of you, well mainly one member, have convinced me the AC outlet in our engine compartment, used for the BoatSafe heater, is not such a good thing.

I plan to remove the outlet. I will need to connect the AC wire from the panel, which has a breaker on it, to the wire coming out of the heater. This connection will be in the engine compartment.

What do I need to use to make this connection to be 'legal' and safe? My first thought is splice them together, use wire connectors, wrap the connection with electrical tape. Is this OK to do for this application though?

Thanks
 
My thought would be that an unbroken cable running from the heater to the breaker panel would be best. How long is the cable coming out of the heater? If it is too short, is there any apparent way to remove the existing cable and replace it with something longer?

Who ever installed the Boatsafe heater for the PO of our boat installed a longer cord on the heater. It looks like they cut the ends off of an industrial grade extension cable and used that to connect the heater to AC outside of the engine space.

Henry
 
So lots of you, well mainly one member, have convinced me the AC outlet in our engine compartment, used for the BoatSafe heater, is not such a good thing.

I plan to remove the outlet. I will need to connect the AC wire from the panel, which has a breaker on it, to the wire coming out of the heater. This connection will be in the engine compartment.

What do I need to use to make this connection to be 'legal' and safe? My first thought is splice them together, use wire connectors, wrap the connection with electrical tape. Is this OK to do for this application though?

Thanks
in a perfect world there would be no splices, however the best way I think is to make connections with suitable connectors within a blue plastic work box leaving no exposed wire and then sealing the box the idea behind removing the factory plug is the potential for arcing in the engine compartment due to the possibility of the plug moving. Despite the fact the appliance may be safe the plug should come off and hard wire should be made.
 
No, the wire coming out of the heater is not long enough.

I thought about this. I need to take the heater apart to see how it's connected. I am not a fan of doing this only for 1) warranty issues and 2) if there ever is a fire one could say I tampered with the heater.
 
The AC wiring should be a continuous run back to the panel, without splices.

If a splice is desired, then it should be within a junction box w/ an accessible cover.
 
..... My first thought is splice them together, use wire connectors, wrap the connection with electrical tape. Is this OK to do for this application though? ....

NO!!!!!!! But I'll let that 'other member' give you the detailed answer....

wingless said:
If a splice is desired, then it should be within a junction box w/ an accessible cover.

Splicing needs to be very clearly defined here....'Junctioned' may be a better choice of words...but that's just symantics..
 
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in a perfect world there would be no splices, however the best way I think is to make connections with suitable connectors within a blue plastic work box leaving no exposed wire and then sealing the box the idea behind removing the factory plug is the potential for arcing in the engine compartment due to the possibility of the plug moving. Despite the fact the appliance may be safe the plug should come off and hard wire should be made.

I agree with White Glove. Go to Home Depot electrical department and purchase a weatherproof plastic junction box with appropriate weatherproof clamps. Connections are ideally done with double crimped solderless connectors and shrink wrap. For extra protection, you can cover the supply cord with plastic wire loom where it runs near an engine. This is how block heaters were done at the factory on our boat.
 
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in a perfect world there would be no splices, however the best way I think is to make connections with suitable connectors within a blue plastic work box leaving no exposed wire and then sealing the box the idea behind removing the factory plug is the potential for arcing in the engine compartment due to the possibility of the plug moving. Despite the fact the appliance may be safe the plug should come off and hard wire should be made.

When you say sealed....what 'exactly' do you mean?
 
Winterize your motors and sell the BoatSafe heater and clean the water spots off.I think we are going to have a COLD winter.Remember your marina has lost electric more than I care to remember.You are 90 miles away cold as hell then what are you going to do .Call Wayne.March is coming then Barack Hussein Obama will take care of all your problems with his magic dust.
 
I agree with White Glove. Go to Home Depot electrical department and purchase a weatherproof plastic junction box with appropriate weatherproof clamps. Connections are ideally done with double crimped solderless connectors and shrink wrap. For extra protection, you can cover the supply cord with plastic wire loom where it runs near an engine. This is how block heaters were done at the factory on our boat.

Jacob- Wiring in the bilge/engine room on a diesel boat is very different than on a gas powered boat.
 
When you say sealed....what 'exactly' do you mean?
I used metalic screw down splicer /reducers which make for a very strong connection and heat wrap the entire assembly ,properly strain relieve the conductor into the work box and then schmooky it .I used silicone.It makes for a water /vapor tight instal and quite safe. By the way , I think most companies void their warranty as soon as the factory plug is cut,I am not sure about Boatsafe but I cut mine none the less.
 
I used metalic screw down splicer /reducers which make for a very strong connection and heat wrap the entire assembly ,properly strain relieve the conductor into the work box and then schmooky it .I used silicone.It makes for a water /vapor tight instal and quite safe. By the way , I think most companies void their warranty as soon as the factory plug is cut,I am not sure about Boatsafe but I cut mine none the less.

MM's service dept cut the plug off of my Xtreme heater, ran the wire through exisiting conduit to the plug box in the compartment fwd of my cockpit refigerator.
 
I used metalic screw down splicer /reducers which make for a very strong connection and heat wrap the entire assembly ,properly strain relieve the conductor into the work box and then schmooky it .I used silicone.It makes for a water /vapor tight instal and quite safe. By the way , I think most companies void their warranty as soon as the factory plug is cut,I am not sure about Boatsafe but I cut mine none the less.

Ours did not come with a plug.
 
Jacob- Wiring in the bilge/engine room on a diesel boat is very different than on a gas powered boat.

Perhaps you could explain the differences in wiring for us.
 
The sand-colored box in the lower right corner is a factory-installed AC junction box.

OilChangeFuelCutoffFireExtinguisher.jpg



The gray waterproof box to the left of my new charger is the direct panel feed for my charger. The wire inlet has a gland compression fitting. The charger is shown plugged into the NEMA 5-20 receptacle w/ a NEMA 5-20 plug.

That receptacle is handy when working in the engine room.

CharlesCharger.jpg
 
Great pics

" gray waterproof box"

It looks like this has a plastic lid/cover?? Is this cover/box a way of making this application 'spark' proof? Looks like you have gas engines too.

Where did you buy this box/cover?
 
Yes, gas engines.

The AC feeds from that receptacle to the adjacent battery charger. Within the ignition-protected charger there is a terminal strip where the wiring connects.

The charger is wide-open to fumes. It is drip-proof only.

There is no spark at the receptacle, within the receptacle box or at the charger terminal strip unless the connection is made or broken while power is applied.

This is safe in my application.
 
Yes, gas engines.

The AC feeds from that receptacle to the adjacent battery charger. Within the ignition-protected charger there is a terminal strip where the wiring connects.

The charger is wide-open to fumes. It is drip-proof only.

There is no spark at the receptacle, within the receptacle box or at the charger terminal strip unless the connection is made or broken while power is applied.

This is safe in my application.

"unless the connection is made or broken while power is applied"

So, like others here have suggested to me, you are not concerned about a spark?

Here is our box:

http://www.hubbellcatalog.com/wiring...e&PN=HBL60CM83

and here is the receptacle:

http://www.discountmarinesupplies.co...ECEPTACLE.html

They seem similar to me.

I agree there is the chance of a spark, but only if there is movement at the connection, right?

No, not being an idiot here, I understand the potential risk, just asking questions.
 
This does not conform to ABYC standards, 'cause some idiot could pull the plug w/ a pool of gasoline in the bilge and game over.

You decide if that is acceptable on your boat.

The only time I have gas fumes is when servicing the fuel system.

This risk is acceptable to me on my boat.

Both the receptacle and the box match the parts I've used.

Also, I wanted a receptacle handy for short-term engine room tasks.
 

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