Can the circuitry handle an electric space heater

[wacnstac]

Hi,

I just bought a 1500 watt (max) oil filled radiator type heater to augment my furnace. I think this will work great with the register from the furnace blowing over the fins of the heater. My question is whether the circuitry of my 1979 31' International can can this 12.5 amp load let's say at a continuous duty.

[balrgn]

Originally Posted by wacnstac

Hi,

I just bought a 1500 watt (max) oil filled radiator type heater to augment my furnace. I think this will work great with the register from the furnace blowing over the fins of the heater. My question is whether the circuitry of my 1979 31' International can can this 12.5 amp load let's say at a continuous duty.

I use one in mine when hooked to shore power, never had an issue.

have on occasion, run an extension cord form "outside" to power it when I found the voltage to be low (@ or below 104)

[HowieE]

In a word NO. You can plug it in and it will run however depending on which circuit you are using within the trailer you may just over heat that wire or the combined load of all the circuits in the trailer. Assuming you are using your refigerator on electric and your convertor you would overload either of the circuits if you plugged in the heater.

If you question these comments just plug your heater in , for 1/2 hour or so, while other normal electrical items are operating then go feel the shore core at the receptacl or open the panel box and feel the wire as they come out of the breakers.

Unless I turn my refigerator to gas, and use that circuit, I limit any heater in the trailer to 750 watts ans use a heavier blanket.

[wacnstac]

The only other electrical item of significance that would be running is the convertor. My fridge is run on propane only this would be for night use, so not a whole lot else going on in the trailer except running the furnace at the same time.

Using the circuit for the fridge is a good idea, assuming that it is the only thing on the circuit, but plugging the heater into this circuit would be tough since the outlet is on the outside in the fridge compartment.

[wacnstac]

After reviewing my circuit diagram it looks like it would be fine to plug the 1500W heater into appliance circuit which powers the fridge (not used), microwave, not being used, and has an outlet in the dining area. This circuit does not have the univolt on it and is rated for 20A. Should be more than enough for the 1500W.

[Pecos Pete]

I use a 1500 watt Vornado heater all the time without a problem. I plug it into the kitchen appliance outlet or the outlet under the dinette. I usually turn it off when using the microwave - has never blown the breaker, but it is just a thing I have.

[TomW]

Originally Posted by HowieE

In a word NO. You can plug it in and it will run however depending on which circuit you are using within the trailer you may just over heat that wire or the combined load of all the circuits in the trailer. Assuming you are using your refigerator on electric and your convertor you would overload either of the circuits if you plugged in the heater.

If you question these comments ...

A wire will not overheat if the Airstream's circuit breakers are in good order. A wire can safely feel warm to the touch even in a new home or trailer and still function fine & meet code. My 1500 watt heater cord gets warm to the touch, but the cord is only 16 gauge wire as opposed to the larger 12 gauge wire used to wire 120 vac outlets. I do not consider this an issue.

To all vintage owners: If in doubt, replace the breakers.

To everyone: If the load is too much, the breaker will trip long before the Airstream's internal wiring approaches anywhere near an unsafe temperature.

If the combined load gets too high, the main breaker will trip. If that should happen, turn appliances off accordingly. But an RV refrigerator does not pull that much current; my space heater & refrigerator have coexisted on the same circuit before.

Tom

[balrgn]

Originally Posted by TomW

A wire will not overheat if the Airstream's circuit breakers are in good order. A wire can safely feel warm to the touch even in a new home or trailer and still function fine & meet code. My 1500 watt heater cord gets warm to the touch, but the cord is only 16 gauge wire as opposed to the larger 12 gauge wire used to wire 120 vac outlets. I do not consider this an issue.

To all vintage owners: If in doubt, replace the breakers.

To everyone: If the load is too much, the breaker will trip long before the Airstream's internal wiring approaches anywhere near an unsafe temperature.

If the combined load gets too high, the main breaker will trip. If that should happen, turn appliances off accordingly. But an RV refrigerator does not pull that much current; my space heater & refrigerator have coexisted on the same circuit before.

Tom

Good clarification, ya beat me to it

[Poprivet]

I have used oil filled heaters for radiant heat in my RV for years and I like it. No noise, no fuss. It's currently under the table between two barrel chairs. If it is really cold. I open cabinet doors and have a small electric fan I use to get greater circulation. I have never had a overload situation.

I will say that the electrical circuits, both AC and DC, should be a regular preventive maintenance item. Clean, tighten, and clean. Look for indications of overheating. Good grounds are very important for the proper operation of you RV.

[john hd]

the breakers are not the problem it is the outlets.

airstream used a daisy chain type outlet similar in construction to those el cheapo blue splices common in the automotive market.

the idea was to remove the outer covering on the romex then press the seperated wires into the back of the outlet.

when the back cover of the outlet was pressed into place the wires were forced into groves that pierced the insulation and made electrical contact. the contact area ia about 1 millimeter wide.

at any rate it is a sub standard connection that will overheat.

if you plan on running a space heater or any other high load device do yourself a favor and remove the outlet from the wall and take a look see. changing it out to a conventional screw terminal outlet will prevent overheating.

this is a good place for an old lineman's adage. when in doubt change it out!

john

[TomW]

Originally Posted by john hd

the breakers are not the problem it is the outlets... the idea was to remove the outer covering on the romex then press the seperated wires into the back of the outlet. ...

when in doubt change it out!

My vintage Airstream did it the right way by looping the wires around the outlet's screws. There is no better connection than that.

I still think breakers are the optimum starting point.

I agree, John, that stripped wires crammed into the back of the outlet is a poor choice for a good connection. But it is expedient. Everything nowadays appears to focus more on getting the job done quickly as opposed to doing the job well.

Does anyone know what year push-in connectors (like John mentioned) were accepted as code?

Tom

[Poprivet]

Originally Posted by john hd

the breakers are not the problem it is the outlets.

airstream used a daisy chain type outlet similar in construction to those el cheapo blue splices common in the automotive market.

the idea was to remove the outer covering on the romex then press the seperated wires into the back of the outlet.

when the back cover of the outlet was pressed into place the wires were forced into groves that pierced the insulation and made electrical contact. the contact area ia about 1 millimeter wide.

at any rate it is a sub standard connection that will overheat.

if you plan on running a space heater or any other high load device do yourself a favor and remove the outlet from the wall and take a look see. changing it out to a conventional screw terminal outlet will prevent overheating.

this is a good place for an old lineman's adage. when in doubt change it out!

john

Yup!

[Boondocker]

I was full timing right up untill early Feb. I used an oil heater from october on with no problems.

[lewster]

Originally Posted by john hd

the breakers are not the problem it is the outlets.

airstream used a daisy chain type outlet similar in construction to those el cheapo blue splices common in the automotive market.

the idea was to remove the outer covering on the romex then press the seperated wires into the back of the outlet.

when the back cover of the outlet was pressed into place the wires were forced into groves that pierced the insulation and made electrical contact. the contact area ia about 1 millimeter wide.

at any rate it is a sub standard connection that will overheat.

if you plan on running a space heater or any other high load device do yourself a favor and remove the outlet from the wall and take a look see. changing it out to a conventional screw terminal outlet will prevent overheating.

this is a good place for an old lineman's adage. when in doubt change it out!

john

John,

These 'RV outlets' are the industry standard. They are found in every RV I have ever worked on. I hate them......but that's what they use. They are called 'speedwire' outlets and switches. They handle 15 amps on a regular basis but I agree that the concept is one of pure convenience, not safety. In fact, household Romex should not be used in an RV that rumbles down the road as the solid copper wire will eventually work harden from the constant vibration and break. It should be stranded marine cable....but that's another story for another time.

BTW, these outlets should be wired WITHOUT the insulation being stripped from wires. The problems arise when they are stripped first, as the wire alone will not hold properly in the clamp. They are designed for only TWO wires per clamp!!! I have seen some OEMs try to squeeze in 3 by stripping the insulation before assembly, but this method is doomed to failure and I usually find them shorted to ground.....causing all kinds of problems in the coaches.

wacnstac,

I've been using the oil-filled radiators for as long as I can remember. They WILL NOT need the fan blowing behind it, as they set up their own convection currents and will warm the entire trailer. I had 2 in a 40' MoHo and they did the whole thing nicely!

[john hd]

lew

you might find it interesting but we are starting to use stranded wire for transformer jumpers in the utility industry.

there are many oldtimers that still insist on using solid #4 wire for common transformer installations. we have found over time the stranded equivilent #4 copper wire handles power line vibration much longer.

one of the more interesting trouble calls i got was a 200 unit retirement complex with part power, some residents were trapped in the elevators. when i arrived i found the solid wires feeding the transformers had broken due to vibration caused by wind blowing over the conductors. the installation was less than 10 years old.

when it moves or shakes stranded wire is better.

since we have to deal with what is standard in the rv industry upgrading the outlets is a good idea.

john

[Poprivet]

Quote "I've been using the oil-filled radiators for as long as I can remember. They WILL NOT need the fan blowing behind it, as they set up their own convection currents and will warm the entire trailer. I had 2 in a 40' MoHo and they did the whole thing nicely!"

Interesting, Warm air tends to rise and cold air tends to sink so convection currents certainly work for you. Still, I found that, although most of the time I did not need a small fan to circulate the air when using a radiant heater, when it was really cold, like 40F and down, a small fan really helped. Could it be my imagination?