Visit our Popular Forums

SilverWind · 07-23-2019, 04:27 PM

I'd like to run my 2017 25 FB's AC during hot weather with 20 amp service in the campground. Is this safe to do?

rmkrum · 07-23-2019, 04:35 PM

It’s possibly a marginal situation. If you don’t get sufficient voltage to your air conditioner when it starts and runs, you could cause damage to the compressor or other components.

You might be able to get away with it if you shut down all other loads in your AS including the converter.

We ruined our original air conditioner by running on low voltage for an extended period a few years ago. Compressor burned out and died a messy death.

I plan to install a MicroAir EasyStart module to reduce current draw and protect our current unit better before our next trip.

Search forums for more details on this device. Highly recommended and effective upgrade, in my opinion.

uncle_bob · 07-23-2019, 04:46 PM

Hi

Another variable - how do you plan to hook up to the 20A service at the campground? Finding an "extension cord" that really is set up for 20A service is a bit hard. Adapting to a 30A cord is probably the better approach.

Bob

batman · 07-23-2019, 04:57 PM

Once started it will run fine however there is a possibility your start up capacitor is not able to start the compressor on the AC. If that happens to often there is a possibility of damaging the compressor, tripping breakers, etc.

Some have found the solution is to replace the stock starting capacitor with a "Hard Start" type of capacitor. Which is (sort of) like unplug the old capacitor and plug the new one in, each comes with instructions.

Some have gone with a more advanced unit called a "Soft Start" or "Easy Start" type of capacitor with added electronics to help maximize efficient starting of your particular compressor.

https://www.youtube.com/watch?v=p2K0ptvYb6Q

-Dennis

uncle_bob · 07-23-2019, 05:31 PM

Hi

Backing up a bit ....

Even with modified starting, the typical A/C is going to pull 13 to 16A while running. How much it pulls is very much a "that depends" sort of thing. High humidity is one obvious driver.

The plug on the post may be rated for 20A. If you have a normal extension cord, it might well be rated for less. Even if it's rated for "enough" it may create a voltage drop while in use. Longer cords need to be heavier cords to keep this from happening.

As the voltage drops, the A/C pulls more current to keep things going. That means more drop on the line and yet more current. It also means more wear and tear on the A/C even if it appears to be running ok.

Bob

Bill M. · 07-23-2019, 05:40 PM

If you are going to do it buy a little plug in AC voltmeter. Watch it for voltage. Cut off the power converter. Cut off the WH. Put the refrigerator on propane. Set the AC to the full cold setting so that the compressor only has to start once. My guess is that it will work fine. Ours does. I am not guaranteeing that you will not hurt it. But if you are prudent and watch for voltage drop or pull down it should be fine.

If you can rig a way to go through your Progressive Dynamics EMS with the 20 amp line that would be the best way. An adaptor should do that. It will monitor for low voltage and prevent damage from restarting. One way that AC's get hurt is for the power to switch off and then come back on in a short cycle. I would worry about that on a 20 amp line.

The Easy Start makes it start with less power but does not reduce the power required to actually run the AC.

kittmaster · 07-23-2019, 06:28 PM

This is the extension cord you can use for 20 amp service....note that one of the blades is sideways on purpose.....denotes 20 amp service....the plug should be romex 12 gauge if it really is 20 amps from the service panel.

https://www.amazon.com/Conntek-Outdo.../dp/B07BNV4GL8

SilverWind · 07-23-2019, 10:02 PM

Quote:

Originally Posted by uncle_bob

Hi

Another variable - how do you plan to hook up to the 20A service at the campground? Finding an "extension cord" that really is set up for 20A service is a bit hard. Adapting to a 30A cord is probably the better approach.

Bob

It will be a situation where hundreds of Airstreams will share electricity and be provided with 20 amp service. If the connection box allows for a 30 amp "male" we'd connect our SurgeGuard and normal 30 amp cord to the trailer. Otherwise I'm not sure.

J. Morgan · 07-23-2019, 10:31 PM

Heres the bottom line if you'll have it, I operate on a couple of twenty amp circuits for weeks and months at a time, use an amp and volt gauge, use them toward not being stupid and your Airstream will never know the difference between a 20 and 30 amp service.

uncle_bob · 07-24-2019, 07:07 AM

Quote:

Originally Posted by SilverWind

It will be a situation where hundreds of Airstreams will share electricity and be provided with 20 amp service. If the connection box allows for a 30 amp "male" we'd connect our SurgeGuard and normal 30 amp cord to the trailer. Otherwise I'm not sure.

Hi

If you are talking about a rally sort of setup then the answer is no.

It's not just the 20A part of things, it's all the structure "upstream" of your plug. Try to pull starting current through that and you likely will create all sorts of issues. ( = it's not really a 20A circuit ).

Bob

tcrum · 07-24-2019, 09:57 AM

easy start dropped our staring amps to around 13 vs no east start we were at 23 amps. I wouldn't plug into power and run the a/c without an easy start if you only have 20 amp service.

Magnet18 · 07-24-2019, 11:58 AM

First hand experience, large risk of overheating a connector if you do it for an extended time

If you do, monitor closely, and run everything else on propane

SilverWind · 07-24-2019, 02:25 PM

Quote:

Originally Posted by uncle_bob

Hi

If you are talking about a rally sort of setup then the answer is no.

It's not just the 20A part of things, it's all the structure "upstream" of your plug. Try to pull starting current through that and you likely will create all sorts of issues. ( = it's not really a 20A circuit ).

Bob

So its sounds like surges and outages upstream are the risks whether you have an Easy-Start or not. I wonder if that is amplified with a large group of trailers.

hhendrix · 07-24-2019, 02:31 PM

I installed easy start in both my A/C's. In my experience the "hard start" capacitors do not perform near as well. Before installation, start up current draw was 46 amps. After, it dropped to 19 amps and eventually 16 amps since the easy start has a learning curve. Mine one A/C will easily run on a 20 amp circuit as long as other factors are considered.

Obviously a good power source is a must. But also altitude and high outside temperatures can affect performance. Depending on those conditions my A/C's after initial start up run on 13 to 16 amps. Again, depending on external conditions, I can often run both A/C's on 30 amp service.

I also have a Southwire EMS surge protector with wireless readout, so I know exactly what each appliance is drawing in amps and watts.

If the power source is 20 amp, you need to eliminate other current draws, like refer (3 amps), water heater (10 amps), microwave (10 amps), and converter (variable draw). Same thing if I want to run both A/C's on a 30 amp service.

Peterf · 07-24-2019, 07:05 PM

Recently I was told by Colonial that AC warranty is void if EasyStart is installed. I don’t see any reference to this issue in this thread. Anyone concerned?

ghaynes755 · 07-24-2019, 07:19 PM

Peterf EasyStart will cover any damage. Federal warranty law would make it had for Dometic to deny a claim as they would need to prove that the Easy Start was the underlying cause. Magnus Ferguson Warranty Act.

Bill M. · 07-24-2019, 08:55 PM

Apparently the new airconditoners have a high failure rate and the warranty has value because of the poor quality of the units. So maybe it would be better to wait until after the warranty expires or to have the easy start installed as a plug in so it could be removed if the AC fails.

No, I have no concerns about the Easy Start causing a failure. But if one is unlucky enough to install it on a bad unit that could be expensive if they void the warranty.

uncle_bob · 07-25-2019, 06:52 AM

Quote:

Originally Posted by SilverWind

So its sounds like surges and outages upstream are the risks whether you have an Easy-Start or not. I wonder if that is amplified with a large group of trailers.

Hi

It's worse than that. If you have hundreds of trailers involved, you would need thousands of amps (like > 2,00) to feed the "network". If you have ever seen 2,000 amp cable it's massive stuff. The "normal" approach is to "go small" somewhere and hope that not everybody pulls the full load.

These days, with lots of cool stuff in trailers, (and if it's hot out) everybody may pull "at least the full load". Things go downhill quickly at that point.

The same "go small" approach means that voltages drop as the load increases. It's the same death spiral as with the extension cord. Your starting amps is not a single number, and it's actually difficult to measure. That creates spikes and dips as well.

It is a good bet that the group is fed off of two or three phase AC. If you pull a lot of current on just one leg of a 2 or three phase circuit the voltage on the other side goes up. If you nose around here, there is a recent thread on a bunch of trailers getting nuked as a result .....

Lots of variables. Lots of problems.

Bob

RivaHaven · 07-31-2019, 09:15 AM

We fitted Micro Air Easy Start and have run out FC25 air conditioning on a 15 amp outlet without any problems. It’s the start up current that is the killer... once it’s running the draw is much lower. I’ve written more details at https://www.facebook.com/10833304684...788208&sfns=mo

suncoasteng · 07-31-2019, 10:12 AM

Quote:

Originally Posted by SilverWind

I'd like to run my 2017 25 FB's AC during hot weather with 20 amp service in the campground. Is this safe to do?

No problem, just make sure the 20A extension cord and the 20/30 Adapter plug are placed on a non-combustible surface or supports so that when one of them starts to overheat and melt down, you dont start a fire that burns down your TT or the Class A coach in the site next to you. And have good liability insurance.