Freezer Too Warm

[sailorboy1]

I have a spillover system with a fan and return hole between the larger freezer and the "refrigerator" side. The past week the refrigerator side has been too warm, which of course means the freezer isn't cold enough. The refrigerator side has been getting into the low 40s where it used to stay pretty much around 35-38. Normally this is a sign that the freezer needs defrosting.

I normally have to defrost every 7-10 days if we have been on the boat full time. The other day the temperatures were too warm and I defrosted again after only 3 days even though the ice layer didn't seem all that thick. Normally the refrigerator side temp would return to the 35-38 range shortly after a defrosting. But it isn't really cooling down and this morning was 38.5 when I got up.

I got a thermometer for the freezer as the frig side has a digital controller for the fan with read out. I used to be able to get the freezer down to 17F, but now it doesn't want to go below 25F.

Things I've tried/checked:
- I redid the seals as the frost of course is an air issue
- I checked the spillover fan operation and it's working
- I cleaned the evaporator (it was pretty dirty even though I have a filter in front of it). This made a big difference in air flow through the condenser and across the compressor, but didn't seem to do anything far as freezer temp.
- I considered that it was just a lot warmer out. But when I closed up the boat and ran the air conditioning it didn't affect the freezer temp.
- the evaporator plate gets fully frost covered
- the compressor appears to be running at full speed and is drawing about 5 amps (BD50 system)

I've only had the digital read out on the refrigerator side for about 6 months. So it has mainly been running in cooler weather till recent so maybe my system has always had these temperatures. But that in my mind doesn't explain why the freezer could get down to 17 a week ago, but only 25 now.

Could it be that the pressure got high last week at the 17 degrees and dirty condenser and leaked some refrigerant?

[Richard Kollmann]

Originally Posted by sailorboy1

I have a spillover system with a fan and return hole between the larger freezer and the "refrigerator" side. The past week the refrigerator side has been too warm, which of course means the freezer isn't cold enough. The refrigerator side has been getting into the low 40s where it used to stay pretty much around 35-38. Normally this is a sign that the freezer needs defrosting.

I normally have to defrost every 7-10 days if we have been on the boat full time. The other day the temperatures were too warm and I defrosted again after only 3 days even though the ice layer didn't seem all that thick. Normally the refrigerator side temp would return to the 35-38 range shortly after a defrosting. But it isn't really cooling down and this morning was 38.5 when I got up.

I got a thermometer for the freezer as the frig side has a digital controller for the fan with read out. I used to be able to get the freezer down to 17F, but now it doesn't want to go below 25F.

Things I've tried/checked:
- I redid the seals as the frost of course is an air issue
- I checked the spillover fan operation and it's working
- I cleaned the evaporator (it was pretty dirty even though I have a filter in front of it). This made a big difference in air flow through the condenser and across the compressor, but didn't seem to do anything far as freezer temp.
- I considered that it was just a lot warmer out. But when I closed up the boat and ran the air conditioning it didn't affect the freezer temp.
- the evaporator plate gets fully frost covered
- the compressor appears to be running at full speed and is drawing about 5 amps (BD50 system)

I've only had the digital read out on the refrigerator side for about 6 months. So it has mainly been running in cooler weather till recent so maybe my system has always had these temperatures. But that in my mind doesn't explain why the freezer could get down to 17 a week ago, but only 25 now.

Could it be that the pressure got high last week at the 17 degrees and dirty condenser and leaked some refrigerant?

The freezer temperature is controlled by the thermostat running or not running compressor. Frost on evaporator or leaking insulation does not alter the freezer thermostat’s ability to maintain freezer preset temperature as long as compressor does cycle off.
Refrigerator temperature is directly related of spillover from freezer area normally 20 degrees warmer than freezer temperatures
You report - the compressor appears to be running at full speed and is drawing about 5 amps (BD50 system) Full speed of a BD50 compressor amperage would be more like 6.5 amps if it were trying to reach freezer temperatures. A BD35 at ½ max speed might draw 5 amps.Your reporting that evaporator is covered over with frost would rule out low on refrigerant.

How many minutes during a complete cycle does compressor run?
It always helps to know the manufacturer of your refrigeration system when questioning performance.

[sailorboy1]

never mind it seems to have "fixed" itself

while I'm happy the PFM bugs me, but I know how to handle that

[a64pilot]

Originally Posted by sailorboy1

never mind it seems to have "fixed" itself

It’s likely that cleaning the condenser “fixed” it, but due to hysteresis it took time for it to cool down.
Most of us have fridge systems that just barely get by, so any change, like adding a lot of food may take more than a day to return to set temp.

[sailorboy1]

Took all that into consideration as I waited 3 days before finally posting the thread. I also researched everything before hand. Temperatures hadn’t changed for 10 hours and then PFM happened and all became good.

It’s 35.1 in the frig right now at noon. In 0.1 the fan will even turn off. I’m sitting here almost watching for it :-)

[sailorboy1]

I heard a “click” and turned around and the spillover fan had cycled off

[Sailing Drummer]

Funny you brought this up. We were anchored near you a few weeks ago. That's around when I started having problems with temps in the boxes.

My freezer plate has been frosting up way faster and with more frost than normal. Using an IR thermometer I was getting around 0 to 10 F on the plate. After I scrape the frost off the plate it's -10 to -15F! The frost was thick enough to act as insulation. And since then I've been scraping every day.

I attribute my issue to worn out gaskets on the lids (along with a bad design) and also possibly the weather. After getting confirmation from Rich at Cool Blue I got new gaskets. Also found out the old insulation where the plumbing for the plate goes into the box was deteriorating.

I think a biggest part of the equation has been the weather plus the gaskets. It's been extremely humid in S FL. We're in Key West and it's been like this since North Palm Beach.

When I get back up north I'm going to look into getting someone to help with the lid design and get it right.

[sailorboy1]

Well I’m just up in Marathon so maybe it really is just the weather.

Meanwhile today the refrigerator side has been 35-36 all day (I changed control from 35-38 to 35-36) after I started this.

[billknny]

Originally Posted by sailorboy1

I normally have to defrost every 7-10 days if we have been on the boat full time.

Aside from ANYTHING else, if you need to defrost your unit every week, you have a SERIOUS air leak into your box.

Start with the door gasket, and be sure that it is good because that is the cause 98% of the time. If you are SURE that is good, look for leaks where the tubing and wires penetrate the box.

[a64pilot]

If you have an ice box conversion another place that the humid air can be coming from is the drain. I put a rubber plug in my drain to help stop it.
I want to keep the drain, cause it makes defrosting so much easier.

[sailorboy1]

There’s a plug in my drain

And other than that I’m just going to let it all roll past me

[sailorboy1]

Last month in Sarasota out on a mooring I was having to defrost the freezer every 3 days. Now in Carrabelle in a slip with the air conditioning running I'm defrosting normal time frame of 7-10 days. So the humidity in the boat air is I believe the big factor.

[Richard Kollmann]

Originally Posted by sailorboy1

Last month in Sarasota out on a mooring I was having to defrost the freezer every 3 days. Now in Carrabelle in a slip with the air conditioning running I'm defrosting normal time frame of 7-10 days. So the humidity in the boat air is I believe the big factor.

Moist air infiltration that generates frost in box is always a problem on boat's refrigerator but there are ways to control it:

There needs to be a switch outside box to stop all fans in box before opening lid.

The door or lid seal needs to be the type that is compressed to sealed all the way around opening and tested with the friction of pulling a ribbon through seal.

Small Zip lock bags filled half way with shipping peanuts taking up air space between product in box and lid will reduce frost build up. You can easily move these small pillows out of the way to remove items under neath.

[a64pilot]

We should defrost at lest once a month but often don’t, I’ll admit that often I defrost when I notice freezer temps increasing as our system maintains plate temp, and not box temp so as the insulating ice builds up, box temps goes up.

I’m sure your right about the air conditioning reducing how often defrost if required, never thought about it, but it’s certainly logical.

[sailorboy1]

Originally Posted by Richard Kollmann

Moist air infiltration that generates frost in box is always a problem on boat's refrigerator but there are ways to control it:

There needs to be a switch outside box to stop all fans in box before opening lid.

The door or lid seal needs to be the type that is compressed to sealed all the way around opening and tested with the friction of pulling a ribbon through seal.

Small Zip lock bags filled half way with shipping peanuts taking up air space between product in box and lid will reduce frost build up. You can easily move these small pillows out of the way to remove items under neath.

Thanks

1 week seems average for liveaboard on my boat model based on a survey. I'm OK with that as it only takes about 10 minutes and most of that time is taking stuff out of the freezer first.