Refrigeration cycling

[Don]

We have owned hull 376 about three years now. Had a long running effort trying to get refrigeration to cycle so the solar array we added could carry us through trips to our island destinations in So Cal. First had the refrigerant checked and replaced the cooling fan. Still failed to cycle off. Then tried to recalibrate the thermostat. Still failed. Don’t know why I waited so long but I finally ordered a new thermostat this spring. Bingo! Major difference in electrical draw over a 24 hour cycle. Our 350 watt solar array does a fine job of keeping up with that. The freezer and refrigerator lid still sweat a bit, so may add some insulation to the lids.

[wolfe10]

STRONGLY recommend a remote temperature monitor for the refrigerator. Walmart, etc carry them. Accurite is one of the major brands.

Sure beats ASSUMING that your food is being stored at a safe temperature.

Also, at least on ours, insulation under the refrigerator was poor. Drilled holes, used expanding foam and re-glassed holes. Made a big difference.

We use the remote temperature sensor in our refrigerator on the boat, in the motorhome and even at home.

[Don]

Thanks for the input. I did pick up an electronic remote temp sensor. It’s great to be able to just glance over to see the temperature. Ours came with two sensors. I’ve experimented with the locations. Right now I have on inside the freezer element and the other clipped to the refrigerator door shelf about midpoint vertically in the refrigerator space. I will also take your advice on insulation at the bottom. Any advice on spacing of holes and type of foam to use? Also did you inject any foam between the sloping freezer wall and the hull? We have had some unusually warm days here lately and afternoon sun affects this location directly. Finally, did you add any kind of circulation fan or exhaust near the compressor? The technician who added refrigerant for me felt it wouldn’t be worth the trouble. I store my seat cushions in the lazerette when we are not cruising so air circulation is probably compromised then.

[wolfe10]

Doing a search here for "Refrigerator Insulation" brought up several pages of hits.

This thread is a good start: viewtopic.php?f=16&t=396&p=1574&hilit=r ... tion#p1574

[Don]

Thanks Brett.

[KenKrawford]

Don there are 2 different types of foam insulation generally sold in big box DIY stores. The "Gaps & Cracks" type is usually considered a minimal-expansion and won't deform the lining of your box as it expands. Check the label of the product you buy to be sure it's this type.

[Captain Kirk]

Hello all.

Picking up on this thread now as I want to get an IN/OUT wireless thermometer for the fridge. Checking out Lowe's and Home Depot, most of these units got poor reviews, 2-3 Stars at best.
Has anybody had a good experience with these and what brand names could you recommend.

Many of the negative reviews were around poor reliability (short working life), inaccurate temperature displays I.E) out by 4-5 Deg or more etc.

Even the more expensive units got poor reviews, I'll be checking Defender and other sources.

Thanks

[KenKrawford]

I've bought a couple of weather stations over the years and found that Accurite seems to be a better product than LaCrosse. The remote thermometers that I bought 15 yrs ago to monitor temps in the refrigerator were from Radio Shack.

[Captain Kirk]

thanks Ken
I haven't come across the Accurite products in my searches so far, but must say the recent LaCrosse reviews were not good. Taylor is another brand that had poor recent reviews although earlier reviews were quite good.
It might be that all of these are now made in China and maybe the quality is lower and similar across all the brands.

Thanks again.

[Triumph]

Take a look at this refrigerator temperature monitor. I'm about to write it up for my website www.thebookofsail.com
Search this phrase on Amazon:
SwitchBot Thermometer Hygrometer Alexa iPhone - Android Wireless Temperature Humidity Sensor with Alerts, Add SwitchBot Hub Mini/Plus Compatible with Alexa, Google Home, HomePod, IFTTT

It works with my IPhone . It tracks temp and hunidity over time for 30 days. I think the humidity is good to look at because it can have an effect on the frost build up on the evaporator. You can try things to see if it reduces the humidity. I found that capping off the drain had an effect. Cost is $19.

Before I got the SwitchBot I had installed an engine hour meter (Suzuki Motorcycle) on the compressor to monitor the run time. I also installed a computer fan to blow directly on the compressor. Both were easy to do.

Bill on TRIUMPH

[Captain Kirk]

Bill

I just had a look at the SwitchBot Temp/Humidity sensor for iPhone. Its looks to be a much better solution, but at a higher price. You get what you pay I suppose. I'm going to get one. Like the idea that a separate display unit is not needed, one less thing.
I do have the Victron battery monitor and Victron Solar panel controller, both are "Bluetoothed" to the phone which is just so convenient and means I can access the data from anywhere on or even near the boat.

I'll check out your website.

Thanks for tip.

[ElizabethG]

Bill,

Love your website! Some great ideas and tips.

It's definitely a bookmark for me...

Bill
Atlanta
#193

[Captain Kirk]

Bill
In my last post I wrote the price was higher, but realize I was looking at a color display version. $19 is a great price the monochrome display which what I need.

Thanks again.

[rjengelhart]

Hi,

Bob Engelhart here, SV Andiamo # 464 in Punta Gorda FL.

Just glue gunned some insulation inside my reefer...door & hatches...metal coated roll available in HD, Lowes. etc.

No more condensation, haven't checked my cycling time yet.

[wolfe10]

Hi,

Bob Engelhart here, SV Andiamo # 464 in Punta Gorda FL.

Just glue gunned some insulation inside my reefer...door & hatches...metal coated roll available in HD, Lowes. etc.

"Glue gunned"???

Foam expansible insulation-- that I understand.

If other, please, more details.

Thanks.

[KenKrawford]

When I insulated my ice box I used a radiant barrier similar to this - https://www.homedepot.com/p/Everbilt-24 ... /314983628
3M spray adhesive works great to adhere it to the box liner - https://www.homedepot.com/p/3M-16-75-oz ... /100067550

[wolfe10]

Drilling small holes in the bottom of the refrigerator and injecting expandable foam between it and the hull makes a real difference in R value.

Then re-glass (better) or seal the holes with a polysulfide.

[Captain Kirk]

Just want to add something to this cycling thread that I discovered this 2021 summer season. We had an exceptionally warm summer on the NW coast and with the remote thermometer located in the freezer evaporator I could follow the cycle times quite nicely with the historical trend data displayed on my iPhone.

As the hottest days came along I found the compressor had episodes of not cycling back on; 3 or 4 occasions it was up to 4 hours in the OFF cycle! The compressor would go into a start-up "sequence" but it would not properly start. This of course meant the freezer temp went up, way up! Normally the temp is around 10 deg F and without an ON cycle for 4 hours one over-night period it went up to 33 deg. The ice-cream went soft.

I wasn't near any larger marine centers but was able to talk to a fridge tech by phone. He said the compressor probably overheated and that it probably has a Hi-Temp cut off. He suggested checking the cooling fan. The fan was working just fine but the unit was hot to the touch, so I looked closer.

I found the inlet side of the "radiator" was partially clogged with dust/debris etc. After vacuuming it with the Dyson the overheating issue disappeared and I got through the rest of the summer with no more issues. Also the cycle ON times dropped and of course, the OFF times went up. Much easier for the solar panels to keep up.

In the 5 years I've owned the boat I never even thought to clean it. Probably the PO hadn't cleaned it either - so now its on the annual check list. Keeping it clean has such a major positive affect its like adding lots more insulation, which I had already done a 3 years ago.

[belladonna]

Hello Don - I have # 368 here on the Chesapeake Bay and see in your post that you ordered a replacement thermostat for your Adler Barbour Cold Machine. Where did you order it from and what did it take to replace it, just clip the old red and black wires and splice the new ones in or was it more to it than that??
Thanx, Jim