# Seafrost BD system



## dadio917 (Apr 4, 2011)

well....we beat the frigoboat discussion to death. the other system we are considering is to switch to a seafrost BD system. We would get rid of the old engine compressor and replace the old shore power AC compressor under the aft lazerettes with a new 12V BD system. Also swap out the one big holding plate in the freezer with two new thin plates on alternate sides of the freezer. Maybe put a thermostat controlled fan between the freezer and fridge compartment. Maybe the digital thermostat control for charging the plates during the day while our solar panels are active.

So.....anyone have any comments on the seafrost BD system? Appreciate it.
thanks!


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## RichH (Jul 10, 2000)

Ive been operating a SeaFrost BD-XP w/ straight evaporator plates in a fridge/freezer 'spill-over' arrangement (actually a small bi-metallic 'door' between the fridge and freezer) and seawater aux. cooling for about 12 years and have nothing but good to state about it. This was a replacement of a 'problem' unit with space grabbing holding plates. 

In that time Ive had almost no problems, .... except from 2 nasty lightning strike events. Even then, the folks at Seafrost clearly discussed a temporary 'manual workaround' until I could get a replacement controller, etc. shipped to me in another country. Saved one hell of a lot of frozen food!
In the most recent episode with 'Thor', I mistakenly gave them an errant credit card number, that didn't 'match up', but discovered only after I had left the Carib. Island from where I made the telephone call. They shipped a new controller anyway, assuming that I'd make the correction when I got back into the US in a week or two - How's that for 'service'? 

Based on my own experiences and operating history with SeaFrost and their equipment, Id recommend them most highly.


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## dadio917 (Apr 4, 2011)

Hi Richh,
do you operate your bd-xp on air cooling? If so, how much room do you have to cool it?

we have a 8+ cu ft. setup with about 4 cu ft for freezer and fridge. 500+ AH of batteries, 120A alternator and about 160W of solar. Am thinking of adding another 160W of solar.
thanks!


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## RichH (Jul 10, 2000)

When actually long term cruising, my calculations are that the Seafrost is entirely serviced by my wind-gen the winds are constant - a KISS @ probably at 5-10A average output for where I sail. Solar would be a good equivalent and important especially if you're anchored in the wind shadows of islands.

When in ambient water in excess of 80+°F and above, I usually turn off the pump to the seafrost heat exchanger and run entirely on air cooling, even that the seawater pump consumes a small amount of energy, its still a needless draw on the electrical system when the ambient water temp becomes 'hot'. 
If I were to 'spec' such a system again I might consider to 'oversize' the heat exchanger.

FWIW - I used 4" corrugated metal automotive/clothes dryer 'hose' from the air inlet of the fridge ... all the way down into the near the bottom of the bilge ... even on the hottest days the cooler inlet air from the bilge does _seems_ to help with the 12vdc energy consumption. My house bank is @~500 amp hours, and if the wind isn't blowing, the boat is 'hot', etc., I will need to full recharge the batts every day. A super re-insulation job of your 'ice box' is probably the best place to start. Im only at ~4" of urethane foam. My thoughts are that 'super insulating' ones 'ice box' is the most important vs. total energy draw from the batteries. We use 'ice box' blankets when any significant 'free space' develops inside the fridge in order to fill in all that 'free space'.

hope this helps


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## dadio917 (Apr 4, 2011)

excellent...thank you. I was thinking of doing the same with an air hose into the bilge. Hadn't decided on water or not. wouldn't be hard to T into the watermaker intake and T out to a cockpit scupper drain hose.

one more question...did you install yourself?

btw, spec on our boat says 4" of closed cell foam. I suppose that's similar to yours.


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## RichH (Jul 10, 2000)

Id certainly add the heat exchanger option. As stated, If you intend a lot of hot water sailing Id recommend discussing a much larger heat exchanger. A heat exchanger is a real plus with 'normal' mid latitude water temperatures. 
I use a proper single seacock and _large_ strainer on each hose whenever possible. My preference is to not use 'ganged' hoses from a single seacock. My SeaFrost discharge is separate and straight overboard at about 3-4 inches above the static waterline.

I installed mine myself. I sent detailed drawings showing full x y z dimensions plus a few digital pics of the 'spaces' to SeaFrost and they arranged all the tubing with the proper lengths and with the proper bends. Some of the supplied bends had to be 'adjusted and tweaked' upon installation. ALL the individual components of the Seafrost system come individually already pre-charged with freon and all the tubing connectors are 'quick-fits'. So, you mount and connect all the pre-filled components, the electricals and water hoses .... no need to add freon and the freon circuit remains 'air free and dry'.

The difficult part is when cutting through the foam insulation of your ice box, you REALLY should cover the exposed foam from the cutting process with a thick layer of fiberglass to seal it from any moisture from entering due to the temperature differences. I didn't and had a moisture problem in my 'closed cell' insulation until I corrected (and with the tubing in the way) - Duh.


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## dadio917 (Apr 4, 2011)

not sure if we'll get down below the 20s. Maybe down in to Mexico before heading west to Hawaii and then back up to the pacific northwest. So not sure I want to make more holes in the boat just yet. especially below waterline.

Would spray foam sealant have worked for your insulation breaches? Like Great Stuff?


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## RichH (Jul 10, 2000)

I really have no firm Idea. What I know is that such spray foam isn't customarily used on holes in building walls that communicate to the 'outside'. I do know that fiberglass properly applied will seal the moisture. But, Im a belt and suspenders (and some sticky tape) kind of person who abhors doing things twice.

My working experience with molecular sized stuff is that water vapor easily passes through hermetically sealed stuff and thin walled polymers -- its just a matter of time.


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## colemj (Jul 10, 2003)

When I installed our AB system, it came with a big block of sticky clay-like material to shove in the hole cut through the insulation for the tubes and fully seal both sides of the hole and the tubes through it. This seems to have sealed the hole from moisture ingress, as well as acts as an insulator to block heat transfer. The clay remains very pliable and sticky 12yrs later.

Mark


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## RichH (Jul 10, 2000)

Mark - 
The 'clay' is probably "Plumbers Putty" .... usually provides a good seal but can leak if applied to a moist surface. Thats what I had originally used and still got moisture into my foam.


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## dadio917 (Apr 4, 2011)

think maybe i'll spray some foam to insulate and then glass over that. 

Since our current setup has two sets of tubes (engine compressor and AC compressor) i'll be plugging one set up completely.


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## colemj (Jul 10, 2003)

RichH said:


> Mark -
> The 'clay' is probably "Plumbers Putty" .... usually provides a good seal but can leak if applied to a moist surface. Thats what I had originally used and still got moisture into my foam.


It's definitely not plumbers putty. At least not the type sold in the hardware stores for plumbing applications. It is thick and sticky and doesn't shrink or dry out. Kind of like butyl, but with clay-like qualities.

Mark


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## fallard (Nov 30, 2009)

colemj said:


> It's definitely not plumbers putty. At least not the type sold in the hardware stores for plumbing applications. It is thick and sticky and doesn't shrink or dry out. Kind of like butyl, but with clay-like qualities.
> 
> Mark


Contractors use something similar to plumbers putty to seal around utilities that enter an exterior house wall. It does seem more like colemj describes it and not like the plumbers putty I've used. You might ask a local contractor what they use.


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## UPHILL (Dec 22, 2010)

The stuff is called mastic putty.


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## aeventyr60 (Jun 29, 2011)

UPHILL said:


> The stuff is called mastic putty.


Grasshopper, before you trot on down to home Depot and buy a tube of "contractors" type gooey sheet, be WARNED!

Not all mastics are equal. The stuff supplied with the Adler Barber systems is great on COPPER Tubing...But will eat the alloy tube sets!

Wanna ask how I know?

Maybe Richh could gives us a basic chemistry course on the properties of an alloy eating mastic?

This is stuff the old HVAC pros seem not to understand either.


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## dadio917 (Apr 4, 2011)

aeventyr60 said:


> Grasshopper, before you trot on down to home Depot and buy a tube of "contractors" type gooey sheet, be WARNED!
> 
> Not all mastics are equal. The stuff supplied with the Adler Barber systems is great on COPPER Tubing...But will eat the alloy tube sets!
> .


Ah......Master......You are most wise!

Good point.....think i'll stick with solid insulating material and glass over as suggested.

On my original question...I've yet to find anyone with bad things to say about seafrost BD systems.


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## colemj (Jul 10, 2003)

dadio917 said:


> On my original question...I've yet to find anyone with bad things to say about seafrost BD systems.


Skip Gundlach

Mark


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## RichH (Jul 10, 2000)

aeventyr60 said:


> Maybe Richh could gives us a basic chemistry course on the properties of an alloy eating mastic?


Most silicone based 'mastics' I know produce acetic acid as they cure .... the acetate complex formation and the low pH is going to produce some severe verdigris (copper acetate, etc.) when these tubes 'sweat'. Such is a corrosion potential. 
Id look for something that has an 'oxime' cure .... similar to the single part teak deck caulks.


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## aeventyr60 (Jun 29, 2011)

dadio917 said:


> Ah......Master......You are most wise!
> 
> Good point.....think i'll stick with solid insulating material and glass over as suggested.
> 
> On my original question...I've yet to find anyone with bad things to say about seafrost BD systems.


A few things here.

I re insulated my box while at the police dock in San Diego before shoving off to Mexico. I used 3 sheets of 4' x 8' x 1" thick foam from Home depot.

I cut out most of the original liner and then cut and shaped the foam to fit. I took the foam all the way down to the curve in the hull. In the deepest part of the box the foam is 17" thick, this gets smaller as you work back up the sides. I glued the foam in place with contact cement, about a gallon if I remember correctly.

After all the foam was in place, I used a cartridge of expanding foam to fill in the gaps.Used a trowel to smooth out the bubbles and give a better shape for the glassing part.

I then used a thin fiberglass mat and epoxy resin and covered the entire box interior . Added a coloring agent to give it the "white" appearance. Not so white after all.

The re insulation part of the reefer project is the most IMPORTANT part. Don't skimp here.

Looks like the Seafrost units are at the top end of the quality spectrum. They have tweaked the Danfoss BD compressors with an electronic thermostat, variable speed compressor control, better cooling fans and airflow for the compressor as well. Also, Copper tube sets!


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## Bleemus (Oct 13, 2015)

17 inches is impressive in a fridge! Holy cow!


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## dadio917 (Apr 4, 2011)

How noisy is the BD-XP system? After much inspection I find a great spot for it at the bottom of the quarter berth closet with a fake bottom over it. On one side is the freezer box and on the other side the batteries so coolant tubing and electrical wires could be under 5'.

but its right next to the quarter berth hence wondering about the noise.
thanks


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## jtsailjt (Aug 1, 2013)

dadio917 said:


> How noisy is the BD-XP system? After much inspection I find a great spot for it at the bottom of the quarter berth closet with a fake bottom over it. On one side is the freezer box and on the other side the batteries so coolant tubing and electrical wires could be under 5'.
> 
> but its right next to the quarter berth hence wondering about the noise.
> thanks


I have two units (one for refrig and one for freezer) located beneath the bottom of our bed. It just makes a quiet hum and once its on you're not aware it's making any noise at all. Also, the water outlet is a couple inches above our waterline so if there's no other ambient noise I can barely hear the water trickling back into the ocean alongside. So, if it stayed on all night constantly it would just be a pleasant white noise, but I find that I don't sleep as well because I notice the cycling on/off. My wife doesn't notice it at all. So, I usually turn them off when I go to bed and back on when I get up in the morning but if I forget, it's not worth getting back out of bed for. With the units turned off between about 11PM to 6AM, neither box gets above about 45 degrees F since it's not ever opened during that time, and since almost all of the running time is when the sun's up and we have solar panels, the depth of my daily battery cycling is decreased from what it would be if I left them on all night.

Overall, I'd call it a very quiet system and wouldn't worry about its location being a problem.


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## RichH (Jul 10, 2000)

dadio917 said:


> How noisy is the BD-XP system? After much inspection I find a great spot for it at the bottom of the quarter berth closet with a fake bottom over it. On one side is the freezer box and on the other side the batteries so coolant tubing and electrical wires could be under 5'.
> 
> but its right next to the quarter berth hence wondering about the noise.
> thanks


Most of the noise on the BDXP will come from the magnetically coupled cooling pump for the heat exchanger ..... be sure to mount this pump onto rubber, etc. and not in direct contact with any structural component of the boat.
A good practice for any rotating equipment is to provide a rubber, etc. 'cushioned' mounting so your don't transmit any vibrations ... as 'noise'.

The BDXP should have metal-ized ducting for the intake to the 'small' air blower inside the boxed refridge unit. The intake of the ducting 'can' transmit sound from the 'box' back to the duct intake. So, if this mild white-noise is noticeable in a compartment, simply extend the intake duct to some other place where it can't be heard.


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## colemj (Jul 10, 2003)

RichH said:


> Most of the noise on the BDXP will come from the magnetically coupled cooling pump for the heat exchanger


Is it possible to mount this pump remote from the rest of the unit, where the noise won't be heard?

Mark


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## RichH (Jul 10, 2000)

Mark -
Indeed the cooling water pump can be located just about anywhere ... especially near the boats centerline and below the boat's static water line is best. 
The cooling water pumps are Marsh-type with magnetically coupled impellers .... the impellers have a considerable 'slip', so they can lose prime easily; hence the need to place them below the waterline. 
;-)


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