Propane system malfunction

@Sage - unless you have a generator or adequate solar and battery capacity with an inverter, you can’t use any AC appliance. 

That's handy info! I never knew the specifics of 'open it slowly'...

Sharon_is_SAM said:

Here is an article that @Bayliss posted in another thread regarding a “hung up” cylinder.
https://www.rvtravel.com/hooking-up-an-refilled-lp-cylinder-check-this-out/

....

@Tampakayaker, yes, there's a sensor on the stove that shuts off the gas if the flame goes out.(so it's unlikely, ie pretty improbable!, that the stove gas knob being 'on' would trigger a 'leak' indication - just sayin... - heh!)    

@Sage. Then2018 TaB400 factory inverter 1200 (2000 surge) Watts Pure Sine Wave Power Inverter. Battery drain, with no load is about 1.2 amps.  Your battery is around 200 amps, so any significant appliance like a heater would drain the battery in short order.  The max load you can put on the inverter is 80% of its max load rating, or about 980 watts.  That said, the inverter in our 2018 TaB400 will not run a small microwave.  

pthomas745 said:

@Sage The math for "how much can I run on my inverter" is pretty simple.  I've run a few things on a 1000 watt inverter attached to my battery.  I limited the test to 700 watt appliances: a small hairdryer and the 3qt instapot, both listed at 700 watts.  (I measured them both with a Kill-A-Watt.  Read the label on the appliance you want to use to determine the maximum wattage it might use.)

At 700 watts, the appliance will use 58 amps per hour.  (700 watts divided by 12v).  This is an approximate value, since I don't know how much power the inverter uses. 

I rounded that off to 60 amps per hour, so the math is easy:  I would use 1 amp per minute to use a 700 watt device.  The hair dryer would take care of my hair in about two minutes, not a big deal for even my stock battery.  The instapot takes about 12 minutes to come up to temperature, and then drops to a very small power use.  So, that would be 12 amps.....which, since I only have 40 amps available, is a lot. 

So, the inverters are very useful, but I'm mindful of the tradeoff:  is the convenience of being able to use the device worth the outcome and my amp hour use? (The instapot meal in the middle of nowhere was totally worth it!) Will I be able to recover the power I'm using with my solar panel?

Bigger batteries change the equation, but you still should always do the math. 

Adding on here: as part of this equation, note that pthomas745 knows the number of amps available to use with their battery. This is critical information, and will vary depending on the battery you have. Your battery will list the amps on the label, but unless you have a lithium battery (doubtful unless the previous owner installed one, they are not stock on Tabs), your actual battery usage shouldn’t exceed 50% of what’s on the label. So my 105 amp battery = about 52 actually available for use. And with the 2018 400, your fridge is 12v, so you need to preserve some of that battery capacity or lose your ability to chill food.

Regarding generators, a few things to note that you may not be aware of: Many places have limits on their use because a lot of your fellow campers find the noise they produce disturbing. Those limits can be things like time of day (often not allowed overnight, but some places are extremely restrictive, such as only allowed from 10 am - 12 pm for recharging batteries), by noise level in decibels at a certain number of feet, or by the time of year—in the West, generators are often banned outright during fire season. You’ll need to carry adequate fuel, and you’ll need to be prepared to perform regular maintenance, or you’ll find yourself stuck with a generator that doesn’t work when you need it to. You also need to have room to run it—a minimum of 20 feet from your trailer and anyone else’s, with the exhaust pointed away from both you and other campers—and some method of securing it in that spot, since they’re easily stolen. They can be very helpful to have, but they are absolutely not a cure all for your non-working propane system. Definitely do the research on all this before shelling out that kind of money.

Hopefully you find the answer to your propane woes soon!

m_lewis said:

I see a consistent error in several messages, in this and many other threads, regarding battery capacity. That is using the term amps when the proper term is amp hours.
An amp is a unit of instantaneous current. One amp hour is one amp for one hour. 
...
Some might say I'm being awfully picky here. Consider this: Would you say you tow your camper at 65 Miles when you mean 65 miles per hour? You might say just 65, with MPH inferred, but not 65 miles. It's just wrong.

Not at all.  Thanks for putting out the clear explanation.  It can be a difficult subject to describe.

@m_lewis - as a former clinical educator, I knew that our students only retained about 20% of what we initially taught, so we built redundancy into our program.  So, this is fair warning - you will need to remind us of these units of measurement again and maybe more!  I appreciate you taking the time to share the info, but I think many of us think in terms of the battery being a big bucket filled with “amps” when it is really “amp hrs”.  Someone else mentioned the terminology message not too long ago.  Keep talking - it will sink in😁

Amps is an instantaneous measure of the electrical current in the system.  Amp hours is a measure of energy capacity used or a measure of battery capacity.  Your multiplying amps times hours to measure that energy.  So it's not really amps PER hour, per se.  For a component that draws variable amps over a period of time, you multiply the average amps over that period of time (in hours) to determine the amp hours used.

Watts is the instantaneous power used, which is generally the amps times the voltage.  So a 700W 120V appliance will drawing 5.8 amps (700W / 120V).  A theoretical 70W 12V appliance, like a 12V light bulb, would draw 5.8 amps.  

Hope that helps.