Holding plate/evaporator blues

[TJ D]

Hi All,

Our beloved Glacier Bay system finally gave up the ghost a couple of months ago, and we wound up replacing the system with 2 independent Sea Frost bdxp evaporator systems.

I am not happy about it, at least on the freezer side. The fridge is fine. Here's why.

First, while the GB unit happily held the temperature down in the single digits, the SF unit struggles to maintain 20 degrees at the top of the box. Down at the bottom, it's about 12. We're in Ireland now, so it's better, but in Charleston in July, the damn thing ran around the clock. Even here in Ireland, It won't achieve single digits. We added the water cooling option, so it's not an issue with temps at the units.

A call to SF revealed that they view anything under 28 degrees as an acceptable temperature for a freezer. This is a new one on me. I can tell you that the ice cream doesn't do well in the 20's.

Here's my real problem, however. The SF uses a LOT more energy in real life than the GB did, even with the box 10-15 degrees warmer than before. I'm sure that the SF uses less AH per day than the GB did, but EFFECTIVELY, it uses far more power.

The reason is that the GB would cool like hell while running the engine to charge the batteries, bringing the box temperature down into the negatives. Our big alternator would happily supply the extra amperage while giving the batteries all they wanted. After we would shut down, the freezer side of the GB would pretty much not run all day.

The SF, on the other hand, runs incessantly. It doesn't have a 'high gear' to drop the temp while charging, so it's pretty much just running all the time.

We have no insulation issues, as the boxes are unchanged from what they were with the GB. With the system being new, I can't imagine we have a charge issue. There are 2 plates, occupying 2 full sides of a 6CF box.

I've been pretty horrified by how fast my batteries have been depleting with this new setup.

Any suggestions? Rip out the SF freezer and put a holding plate setup in? I just spent a heap of money on this thing, so starting over is a poor option for sure.

Hopefully, somebody has some insights on this one, other than telling me that I bought a lousy system...

Thanks, TJ

[ColdEH]

Wow, nobody has answered you or offered any suggestions?

Regards

[Paul L]

It sounds like you are asking an evaporator plate to act like a holding plate. The one advantage of a holding plate is that it can use excess power and store it.

[SV THIRD DAY]

Ok...Typhoon's comment brought this post back up to the top and I just saw it or I would have commented earlier.

First that's total BS that anything below 28-degs is considered a Freezer and "acceptable". A marine freezer should be able to get into the Single Digits with good insulation and a system matched pretty decently to the freezer box size. Ice cream need below 9-degs F to get nice and hard and that is certainly capable.

It's normal for the Evap plate to be at least 10-degs colder than the actual box temp, so if you have an IR temp gun, a good test is to shoot the evap temp and see where you are at. Perhaps you will find the evap unit too warm and can make an adjustment to the adjustable Orifice that is used by SF.

Now another issue could be low charge. A unit low on charge would run more and not get as cold. So Charge and then Evap temp would be the first two things I did to troubleshoot this. Something is not right here that's for sure, but and this always is a possibility, that the system you bought from SF is just not capable of handling the Box volume you have. I assume that was talked about and confirmed in the buying process?

This sounds to eerily similar to Skip's SF story:
http://www.cruisersforum.com/forums/...em-131754.html

[ColdEH]

I knew you must have missed this post Rich , you know a lot more then me on this subject . I noticed as well he never mentioned his box size , also don't SF systems come without charge so you have to get someone local to charge them up ? May be the problem right there.

Regards

[SV THIRD DAY]

Originally Posted by typhoon

I knew you must have missed this post Rich , you know a lot more then me on this subject . I noticed as well he never mentioned his box size , also don't SF systems come without charge so you have to get someone local to charge them up ? May be the problem right there.

SF does send the system out precharged, but if the charge is off from a possible leak, that could send the system into "run forever and not cold enough mode"

[TJ D]

Hi all,

We've been sailing from Ireland to England and have been offline for a few days.

Rich, thanks for posting the old thread. Very similar indeed.

We're seeing temperatures at the plates (with an IR gun) of nothing colder than about 0. I've never seen a negative number at the plates, regardless of whether we're using air or water cooling, regardless of outside temp, and we've covered quite a lot of latitude this summer!

I don't really think that there is an insulation issue here. Remember that we are using the same box that the GB inhabited with no problems.

Plate sizing, was of course done with Cleave's blessing.

I guess it's time to give SF a call and see what they have to say for themselves.

I appreciate the responses. I'll post if I learn something useful to the group.

TJ

[TJ D]

Ok, I just had a nice chat with Cleave.

He confirmed that I should expect a box temp of up to about 24 degrees with this system, and that anything under 28-29 is just fine for a freezer. I don't know. I would like it to be colder, that's for sure. Maybe we won't lose food, but it still seems awfully high to me.

The refrigerant/settings that they are using are only capable of bringing the plates down to about 0 (!?).

We're going to mess around with it a little bit. I suppose that I can live with softer ice cream if we can get the amp use down to within reasonable limits. The issue currently is that we're using a TON of power even with the higher box temp.

Typically when offshore, I wind up running the engine from about 1.5 to 2 hours per day to charge. On our transatlantic, our engine time basically doubled. The SF system is the only change in our electrical profile. The pilot might have been working a bit harder than in lower latitudes, but the additional draw of the rougher weather does not account for this change.

I did mention this in my first post. The box is about 6cf. The plates are both frosting up top to bottom. I don't have empirical data on insulation of the box, but we were in the tropics for over a year with the same boxes and no issues with excessive power draw from the GB system.

Now, on the customer service front, SF has been great. No problems with Sea Frost at all. He offered to swap out the freezer compressor with a different one using a different refrigerant/higher capacity for just the cost of shipping if I can't get this thing working in a way that's satisfactory.

I'm a little bummed that we didn't go this route in the first place, but it's possible that I didn't explain things well enough to the installers in Charleston. Anyway, I'm sure we'll get there.

TJ