Norcold Reefer Installation

[Mike Smith]

Hi all -

My new Norcold machine came in last Friday, and I've been planning the installation - looks like a direct swap to me.  I plan to just disconnect the wiring, pull out the old compressor, mount the new one, and reconnect it.  I will swap out the old evalporator, tubing, and switch.  Simple job, but here is a problem: The old unit is AC/DC with both circuits switched through breakers at the distribution panel.  However, the installation instructions for the new unit say CAUTION: CONNECT UNIT DIRECTLY TO THE BATTERY.  The only direct connections I make on Breezer are to the bilge pump and the starter!  

Hmmmmm... any comments or suggestions?

Mike Smith
S/V Breezer
www.mikejansmith.com

[Stu Jackson]

Just a Guess, but...

Mike,

The "direct connection to the battery" is most likely because some people, for some unexplained reason, would connect their fridges to the battery charger outputs!  I know, sounds strange, but it's happened.

For instance, the Adler Barbour instructions say the same thing, but show a breaker (like on your panel) in between the unit and the battery.

You could also call or email Norcold just to confirm, but that's why I think they have this message in their literature.

Stu

[Mike Smith]

Thanks, Stu -
I did e-mail Norcold and their techs said to follow the installation instructions.  There must be something I am missing, or haven't read yet.  The unit automatically switches from DC to AC when dock power is applied, and vice versa when it is removed, so maybe there is protection in that circuit arrangement and the DC connection has an internal breaker.

Mike Smith
S/V Breezer
www.mikejansmith.com

[Mike and Theresa Vaccaro]

Hey Mike,

Have the same system on our '88 and have been following your thread closely since our compressor just failed and we're considering replacing the whole unit.  In the process, I've learned a bit about how the system works.  I think the reason that the manufacturer recommends direct battery hook-up is to ensure that there is always a source of power to the unit (unless the batteries are drained!).  Our DC circuit is actually controlled by a switch on the main electrical panel (don't know if this was a factory installation or not), where we have a switch marked "fridge."  If you're plugged into shore power and it fails for whatever reason (tripped breaker, dock maintenance, etc.), the fridge will automatically shunt to DC power if you are hot-wired to the battery, regardless of any other switch positions.  If you wire your DC source via a switch, you'll have to ensure that it's "on" if you want an auto shunt in the event AC power is removed from the system.  There is a built in circuit breaker (just under the compressor unit cover) in our DC input line.

The bottom line is that either wiring scheme will work, but if you hot wire to the battery and AC power isn't available, you'll eventually drain the battery(ies) unless you've got a solar or wind DC generating system on-board.

Hope this helps, and please post about how the installation went, since I might be doing the same repair shortly!

Cheers,

Mike Vaccaro
'88 #563 "Spirit"

[Mike Smith]

Thanks, Mike -
With your info I have decided to just direct exchange everything and wire it as is, leaving the DC breaker on the distribution panel "On".  I'll take some pictures of the installation if things get tricky - but I don't see how it could!

Mike Smith
S/V Breezer
www.mikejansmith.com

[Mike Smith]

Thanks for the info, Adam -
I intend to leave the compressor/fan where it is - in the forward starboard setee.  I have never noticed an increase in cabin temp, however the area was not well ventilated to start with.  I intend to install louvered insets on both sides of the settee space to promote airflow and increase the unit's efficiency.  The reefer box is probably not insulated beyond what came with the boat.  To do a good job I will probably have to remove the counter top and foam everything from the top - which is my preference. I'll keep you informed

Mike Smith
S/V Breezer
www.mikejansmith.com