Refrigerator heatloss question

ChrisJ

In this article it says "Ambient effect : 0.637kWh per deg-mo".

What does that mean?

Larry_52

Is the average kWh per month based on 60degs ambient? That would make the other part a factor per deg ambient change. Just a guess.

Abracadabra

modern frost free refrigerators will use more because of the defrost heater and fan (and a tiny bit due to timer motor). Not sure if they included the light in the door usage too.

ChrisJ

Abracadabra said:

modern frost free refrigerators will use more because of the defrost heater and fan (and a tiny bit due to timer motor). Not sure if they included the light in the door usage too.

Also due to,

Thinner insulation (Monitor top is 3" thick including the door)
Condenser fan
Evaporator fan

The defrost heater as you mentioned is one hell of a pig.

The CK monitor top had a cabinet light, so no, they didn't compare that.

Either way, 20kWh per month isn't shabby. My machines are CA series and use a little more, typically in the 30-40 area depending. Most seem to assume an antique refrigerator is an energy hog and it's flat out wrong.




Still doesn't tell me what "Ambient effect : 0.637kWh per deg-mo" means.

bob_46

my take : if you are testing 114 units you have to have them all in the same room (ambient) or monitor the temperature at each location . Changes in room ambient from some base temperature will cause changes in head pressure which changes compressor volumetric and overall efficiency not to mention heat gain . I think the 0.637 kWh per degree - Mo means you increase or decrease electric consumption per month by that amount times the degrees of temperature variation from the base temperature .

SWEI

Probably right (though kWH per degree-month above the interior temp might also be interesting.)

ChrisJ

This is my unit that will finally be put into normal service soon. I have the other 2 shelves and a fruit basket that were all nickel plated. They just weren't needed for testing and doing the final charge.

You know all the guys that claim there's no replacement for displacement? They're actually talking about insulation.

ChrisJ

vaporvac

That is so beautiful. Is that going in your kitchen?

SWEI

You're getting me interested in adding another project to the already-bordering-on-untenable "I want" list. Bad.

ChrisJ

@vaporvac
Thank you!
Yes ma'am

Been working on it on and off since 2007. After its put into service I have two more to start on

ChrisJ

SWEI said:

You're getting me interested in adding another project to the already-bordering-on-untenable "I want" list. Bad.

Be careful, it ended up being a lot more work than I expected. As I said this one started in 2007 as a free refrigerator and it's far from that now.

High side float valve had damage to the seat so I converted it to a capillary tube.

Crankcase heater was burned out so had to order a few custom made 12mm x 2.5" 12W heaters.

Door hinges had too much wear on them.

Door handle was beyond repair.

New reproduction door gasket.

New reproduction black plastic feet that go under the legs.

Found an original GE Chiller Tray that sits under the evaporator.

Sandblast racks and get them nickel plated.

Sandblast top and paint it, 5 coats.

Start relay was buzzing so converted it over to a solid state one with built in overload. May change my mind and go back to a mechanical one though as the solid state one makes it so it can't restart immediately. This makes the unloader pretty much useless.

Had to grind all of the rust along the edges of the porcelain enameled panels \ legs off and paint it with a brush.

Sand surface rust from bottom and paint.

All new wiring which is a pain and you almost need to tear the entire top apart to do it.

Grind out deep rust from top plate (plate under compressor that forms top of cabinet from inside) and bondo holes then paint. New insulation added after that.

New cork, insulators and 316 SS hardware to bolt evaporator to top plate.

Bought 2 liters of new Methyl Formate which is kind of cool because it comes in a glass bottle and you pour it in via a funnel.


Of course I needed refrigeration tools,

Robinaire 2 stage vacuum pump and a gallon of oil.

Yellowjacket micron gauge

rare adapter for charge valve on fridge (bought 2 as I found them).

TurboTorch swirl type acetylene torch with 3 tips and tank.

Nitrogen tank and regulator.

Brazing rods, I think 15% sil-phos but can't remember.


I'm well into the thousands of $$ on this project but the good news is most of that can be used to restore the other two as well so that's nice. I also love the torch and haven't used my Bernzomatic MAP torch since even for plumbing work.

Learning to braze was easy but working with flammable refrigerant was less than fun.

This video has been floating around for a long time but for those who haven't seen it.

https://youtu.be/y2LWjT3e7uQ

Abracadabra

Chris, I'd be careful. Your boiler may get jealous and take out the frig!

Fred

Great job Chris! It's beautiful.

vaporvac

Now all you need is a Chambers stove! Not as much work as it's mostly mechanical, but the end result is worth it. It's a cooking machine and that fridge needs a partner.
The effort shows, @ChrisJ. It's a beautiful redo. can't wait to see it in its home.

ChrisJ

vaporvac said:

Now all you need is a Chambers stove! Not as much work as it's mostly mechanical, but the end result is worth it. It's a cooking machine and that fridge needs a partner.
The effort shows, @ChrisJ. It's a beautiful redo. can't wait to see it in its home.

I'd love an old stove. Not 1940s - 1950s, but much older with the legs etc.