Isotherm fridge stopped working on AC

[Constellation1]

My Isotherm CR195 stopped working on AC power yesterday. I switched to DC and everything is working as it should. I checked the AC power line and everything is working as it should.

Has anyone seen this before? Is the fix as simple as installing a new controller?

 

[catalinajack]

My Isotherm CR195 stopped working on AC power yesterday. I switched to DC and everything is working as it should. I checked the AC power line and everything is working as it should.



Has anyone seen this before? Is the fix as simple as installing a new controller?

It is likely the controller which is pretty much just an inverter. Why bother if your fridge continues to work directly on 12VDC? Think about it for a moment. When on shore power, 12VDC is provided by the inverter, not from the batteries. When not on shore power or generator, 110VAC is inverted from your batteries, then suppplied to your fridge where it is then converted by the control module back to 12VDC so double the inversion/conversion inefficiencies. I have never understood the concept of combination AC/DC fridges. Makes no sense considering the compressor runs on 12VDC. Plus, those control modules are just an added point of failure which does happen on occasion. A control module costs about $200.

 

[Constellation1]

I changed the controller today and everything works as it should again. I don’t like broken stuff on my boat - it was an easy fix.

 

[SteveK]

It is likely the controller which is pretty much just an inverter. Why bother if your fridge continues to work directly on 12VDC? Think about it for a moment. When on shore power, 12VDC is provided by the inverter, not from the batteries. When not on shore power or generator, 110VAC is inverted from your batteries, then supplied to your fridge where it is then converted by the control module back to 12VDC so double the inversion/conversion inefficiencies. I have never understood the concept of combination AC/DC fridges. Makes no sense considering the compressor runs on 12VDC. Plus, those control modules are just an added point of failure which does happen on occasion. A control module costs about $200.

Jack, I agree with you.

 

[catalinajack]

I changed the controller today and everything works as it should again. I don’t like broken stuff on my boat - it was an easy fix.

So now your fridge is still running on 12 volts but consuming more electricity but, hey, now you have a brand-spanking new $200 inverter-controller. How long will this one last? Each to his own, as always.

 

[BruceK]

I changed the controller today and everything works as it should again. I don’t like broken stuff on my boat - it was an easy fix.

Catalina Jack will correct me if I`m in error, Soo Valley will surely follow.

On shorepower,is not the Isotherm receiving 110vAC likely covered by marina fees which the much maligned Controller renders to 12volts DC. Bothering neither any central inverter nor the batteries?

 

[Constellation1]

Yep, my boat, my choice.

 

[catalinajack]

Yep, my boat, my choice.

As always for all of us.

 

[catalinajack]

Catalina Jack will correct me if I`m in error, Soo Valley will surely follow.

On shorepower,is not the Isotherm receiving 110vAC likely covered by marina fees which the much maligned Controller renders to 12volts DC. Bothering neither any central inverter nor the batteries?

Not in my marina. Electricity is metered as it was in my previous marina.

 

[BruceK]

Not in my marina. Electricity is metered as it was in my previous marina.

It varies. Current(pun intended) marina includes it, previous marina had a vague "fair usage" allowance, others check metering and charge.

 

[kthoennes]

It varies. Current(pun intended) marina includes it, previous marina had a vague "fair usage" allowance, others check metering and charge.

Yep, and our current marina covers it in the annual slip cost, unless you have air conditioning and then they add a surcharge. $50 for the season I think. Yep, and to each his own on fridge configuration. We just replaced ours with a high efficiency residential 110v fridge on a dedicated inverter with a built-in auto transfer switch, so now the switch is external where the old Norcold had one built-in. May not make the most logical or efficient sense but it worked for me and it didn't exceed my skill level with electricity.

 

[Dougcole]

My Isotherm fridge is currently doing the same thing. For some reason it burns out controllers pretty regularly, though in the past it has been the fan that has failed. For the time being I am just using it in the DC mode, as others have said, it is not a big deal.


But it is a nice feature to have sometimes. A couple of years back when I did a major fuel tank/exhaust hose/house bank project I had the house bank out for three weeks. It was nice to have a working fridge during that period without having to do any rewiring. Could I live without AC capability on the fridge? Sure. But the redundancy is never a bad thing.