How to make the most of 30 amps
Currently on the Oregon coast. I have free electric here so I want to make the most of it. I added a small Greenhouse outside which I am keeping warm with a small greenhouse heater that has a thermost...
Forum Discussion
By this point, it looks like things are off track from the OP's query, but anyway...
Any electric resistance heater itself is 100% efficient however only produce their rated output only if they get 120 volts. Voltage drop in CGs is a very common problem, especially older ones and can be a little or a lot. The heater's output will vary as the square of the voltage. At 10% drop (108 volts) a 1KW heater will put out 810 watts. If you were at 102 volts (15% drop and the point at which a SurgeGuard will cut out), you'll get only 723 watts. (The same principle will affect a fridge's 300 watt element when cooling on electric.) So if camping in colder weather and your heater(s) doesn't seem to be doing a good job, check your voltage.
Dimplex has a little info. on heater efficiency and heater types here.
Infrared type heaters heat objects like human bodies, floors, furniture, equipment., etc. The ceiling mounted types generally require about 10% less watts per square foot compared to conventional space heaters and are a good choice for warehouses and workshops. The oil-filled type heaters work on radiation & convection and are probably a better choice than the little fan-forced ceramic heaters but they are BIG and not suitable unless your RV is also BIG inside, lol. Many plug in a portable heater in living/kitchen area but that will result in the bathroom and bedroom (if a separate room) being cold to icy cold. The built-in thermostats on portable heaters don't work well compared to wall t'stats.
As Wa8yxm mentioned above, there is also the concern of overheated RV type (SCD) receptacles. The ones on the farther end of a wiring run can be more susceptible due to increased number of in/out connections. They are UL/CSA listed for 15 amps however a problem I've found is that the factories sometimes don't punch the wires down on the terminals properly. Installing a dedicated circuit with it's own breaker would be a good idea but the NEC limits the number of breakers in an RV panel to 5 (but you can always install a tandem 15/15 amp breaker).
We have a recessed heater in bedroom, bathroom and living/kitchen area (2KW total on a dedicated circ.) on their own low voltage thermostats and our TT is nice 'n cozy and evenly heated throughout. Rarely use the ridiculously noisy furnace anymore. If RV manufacturers would only do a better job of insulating then electric heating would be a more attractive option and be able to run on lower watts.
pnichols wrote:Agree.
In these heater/heated discussions you often read that "electric heaters are 100% efficient" ... meaning that all of the input electricity is used to make something warm.
I find this a misleading statement, in that not all kinds deliver warmth as effectively.
Any electric resistance heater itself is 100% efficient however only produce their rated output only if they get 120 volts. Voltage drop in CGs is a very common problem, especially older ones and can be a little or a lot. The heater's output will vary as the square of the voltage. At 10% drop (108 volts) a 1KW heater will put out 810 watts. If you were at 102 volts (15% drop and the point at which a SurgeGuard will cut out), you'll get only 723 watts. (The same principle will affect a fridge's 300 watt element when cooling on electric.) So if camping in colder weather and your heater(s) doesn't seem to be doing a good job, check your voltage.
Dimplex has a little info. on heater efficiency and heater types here.
Infrared type heaters heat objects like human bodies, floors, furniture, equipment., etc. The ceiling mounted types generally require about 10% less watts per square foot compared to conventional space heaters and are a good choice for warehouses and workshops. The oil-filled type heaters work on radiation & convection and are probably a better choice than the little fan-forced ceramic heaters but they are BIG and not suitable unless your RV is also BIG inside, lol. Many plug in a portable heater in living/kitchen area but that will result in the bathroom and bedroom (if a separate room) being cold to icy cold. The built-in thermostats on portable heaters don't work well compared to wall t'stats.
As Wa8yxm mentioned above, there is also the concern of overheated RV type (SCD) receptacles. The ones on the farther end of a wiring run can be more susceptible due to increased number of in/out connections. They are UL/CSA listed for 15 amps however a problem I've found is that the factories sometimes don't punch the wires down on the terminals properly. Installing a dedicated circuit with it's own breaker would be a good idea but the NEC limits the number of breakers in an RV panel to 5 (but you can always install a tandem 15/15 amp breaker).
We have a recessed heater in bedroom, bathroom and living/kitchen area (2KW total on a dedicated circ.) on their own low voltage thermostats and our TT is nice 'n cozy and evenly heated throughout. Rarely use the ridiculously noisy furnace anymore. If RV manufacturers would only do a better job of insulating then electric heating would be a more attractive option and be able to run on lower watts.
