Last fall we purchased a used toy hauler with an onboard Onan 5500. It also has a residential fridge. We had the dealer install two golf cart batteries in place of the 12-volt batteries. The tech guy didn't tell us anything about the Xantrex pro display or its purpose. Yesterday I wanted to get an idea of how long the batteries could power the fridge. At 9:00 am I unplugged from shore power. My Xantrex Pro digital display showed 12.8 volts. When I came back 5 hours later, the display was showing an E05 code. I plugged back into shore power. This morning before I left for work, I checked the display again and it was still showing the E05 code.Does anyone know what that code means?Shouldn't 6-month-old golf cart batteries be last longer than 5 hours when powering a residential fridge?

Minimum Power Needed for a Residential FridgeThe minimum power for running solely the residential fridge for 24 hours is six AGM batteries totaling 600 amp hours (300 ah usable). PLUS you need 600 watts of solar power on the roof to replenish the batteries during the daylight hours.Mar 27, 2016

E05 Red Overload shutdownShort circuitReduce or disconnect the load. Make sure the load does notexceed the XM 1800’s output rating.Check connection to the load.Are you certain the inverter only powers the fridge?I assume you may need to cycle the inverter power off/on to get the inverter to restart.What is the battery voltage?

E05 Red Overload shutdownShort circuitReduce or disconnect the load. Make sure the load does not exceed the XM 1800’s output rating.Check connection to the load.The best way to remove the code is to disconnect from Shore Power and disconnect the Coach batteries for 5 minutes and then reconnect the Coach Batteries and plug into shore Power. Hopefully the code goes away. The Xantrex Pro---Can you tell us the Model? Your refer pulls minimal AC current, less than 300 watts, and almost any Xantrex Pro will power the refer OK. Did they install 2-6 volt Golf Cart batteries or 2-12 volt Golf Cart Batteries? Doug

Sounds like you need a battery monitor, and 2 more batteries. Resi fridges get hungry.

Need Some help with my battery system | Good Sam Community

DarkSkySeeker
Explorer
May 27, 2021
Lots of good information here.
jdc1
Explorer II
May 27, 2021
Minimum Power Needed for a Residential Fridge
The minimum power for running solely the residential fridge for 24 hours is six AGM batteries totaling 600 amp hours (300 ah usable). PLUS you need 600 watts of solar power on the roof to replenish the batteries during the daylight hours.Mar 27, 2016
time2roll
Nomad
May 27, 2021
E05 Red Overload shutdown
Short circuit
Reduce or disconnect the load. Make sure the load does not
exceed the XM 1800’s output rating.
Check connection to the load.

Are you certain the inverter only powers the fridge?

I assume you may need to cycle the inverter power off/on to get the inverter to restart.
What is the battery voltage?
dougrainer
Nomad
May 27, 2021
E05 Red Overload shutdown
Short circuit
Reduce or disconnect the load. Make sure the load does not
exceed the XM 1800’s output rating.
Check connection to the load.

The best way to remove the code is to disconnect from Shore Power and disconnect the Coach batteries for 5 minutes and then reconnect the Coach Batteries and plug into shore Power. Hopefully the code goes away. The Xantrex Pro---Can you tell us the Model? Your refer pulls minimal AC current, less than 300 watts, and almost any Xantrex Pro will power the refer OK. Did they install 2-6 volt Golf Cart batteries or 2-12 volt Golf Cart Batteries? Doug
2oldman
Explorer II
May 27, 2021
Sounds like you need a battery monitor, and 2 more batteries. Resi fridges get hungry.
Gdetrailer
Explorer III
May 27, 2021
2oldman wrote:
Sounds like you need a battery monitor, and 2 more batteries. Resi fridges get hungry.

Not all residential fridges are "hungry", mine can easily operate off one pair of GC2 6V batteries for 24 hrs before needing recharged.

Granted, my home fridge conversion I spent a lot of time weeding out heavy power user fridges and opted for a 10 CuFt apartment size fridge which sips power.. Something that most RV manufacturers will ignore..

OP got less than 5 hrs of operation, either batteries were not fully charged before the test or they have additional 12V loads not accounted for..

At the rate the OP is going adding 2 more GC2s would only get them 10 hrs tops so throwing more batteries at the problem doesn't solve the problem..
Dutch_12078
Explorer II
May 27, 2021
It might help to know which residential refrigerator the OP has. Reportedly some refrigerators don't play well with modified sine wave inverters like the Xantrex XM's.
Sagebrush
Explorer
May 27, 2021
With a residential fridge I would want four GC2 batteries minimum if your off shore power often. That should get you two days at least. We had a large double door fridge on an inverter. The residential fridge was nice when full timing, but we ended up preferring the RV/propane fridges. The power use depends on the fridge and how often the doors are opened etc.

Might want to look into Onan's auto start system, works off voltage or inside temperature, it has quite time ability too. Keep those batteries above 50% SOC.
mrad
Explorer II
May 27, 2021
dougrainer wrote:
E05 Red Overload shutdown
Short circuit
Reduce or disconnect the load. Make sure the load does not
exceed the XM 1800’s output rating.
Check connection to the load.

The best way to remove the code is to disconnect from Shore Power and disconnect the Coach batteries for 5 minutes and then reconnect the Coach Batteries and plug into shore Power. Hopefully the code goes away. The Xantrex Pro---Can you tell us the Model? Your refer pulls minimal AC current, less than 300 watts, and almost any Xantrex Pro will power the refer OK. Did they install 2-6 volt Golf Cart batteries or 2-12 volt Golf Cart Batteries? Doug

Two six-volt golf cart batteries.
I will check the model number when I get home.

I have a disconnect switch right at the batteries, and another in the storage area. would turning off the disconnect at the batteries work the same a physically disconnecting them?
mrad
Explorer II
May 27, 2021
Gdetrailer wrote:
2oldman wrote:
Sounds like you need a battery monitor, and 2 more batteries. Resi fridges get hungry.

Not all residential fridges are "hungry", mine can easily operate off one pair of GC2 6V batteries for 24 hrs before needing recharged.

Granted, my home fridge conversion I spent a lot of time weeding out heavy power user fridges and opted for a 10 CuFt apartment size fridge which sips power.. Something that most RV manufacturers will ignore..

OP got less than 5 hrs of operation, either batteries were not fully charged before the test or they have additional 12V loads not accounted for..

At the rate the OP is going adding 2 more GC2s would only get them 10 hrs tops so throwing more batteries at the problem doesn't solve the problem..

I'm wondering if one or both of the batteries is bad. they are only six months old. They had been plugged in to shore power for three weeks. They should have been fully charged.