I have a 12v holding plate unit with a Danfoss D25 compressor. The
compressor will run for a minute or so and then cut out. The air
cooling fan continues running. It will start again and then cut out
again. Over and over. Last week I had a problem with a poor ground and
the whole unit was shutting down (low voltage, beeping ) I fixed
that,(new wiring) there's lots of voltage (no voltage drop) and now I
have the compressor shut down problem. The freon (R12) is good I think
(was frosting up nicely on the weekend). The compressor is not
overheating (it only runs for a minute! I can hold my hand on it for
ever without burning). Is it the control module and is this problem
coincidental or related to the earlier low voltage problem. (the low
voltage problem was intermittent over a week, I used the wire jiggling
method before I finally corrected it by re-wiring). Is it the
compressor? There is no amperage spike when it starts - just the usual
4 amp draw. The unit has run flawlessly for 15 years. I am at the end
of my limited knowledge. Help!


Rick Itenson
La Belle Aurore
Toronto

"Rick Itenson" wrote in message
...
The freon (R12) is good I think
(was frosting up nicely on the weekend).

It frosting up is not a good indication that the Freon level is okay. Many
refrigeration systems include a shut off switch to protect the compressor in
the event that the Freon level is low. I would recommend having someone
test it with the gauges

Rod

There are no pressure switches on these units and the only way that
refrigerant volume could affect this unit would be if it were
overcharged with refrigerant. When you say the compressor stops are
you sure, did the ammeter drop to zero? Standard troubleshooting for
the Danfoss air cooled BD2.5 to follow. Try unit after completing each
item below:

1. Check to see if the airflow through the condenser is adequate and
not restricted 2. Disconnect thermostat wires at electrical module and
place a jumper across module terminals. 3. Check fuse connection on
module and replace fuse. 4. Disconnect black wire on module to fan. 5.
If you have the LED installed on the module and there is a power
problem in the boat it will blink. Without the LED the only way to be
sure this is not a boat wiring problem is to run a set of jumper wires
from a fully charged battery direct to the module. Checking the
voltage drop will not always show the voltage spike unless you have a
very good meter or superman's eyes. 6. This model compressor draws 5
to 6 amps when the box is warm not 4 amps. It the compressor draws
more than 7.5 amps after startup the insulation on the wiring inside
is breaking down and it is time to replace the compressor. There is a
resistance test to confirm the condition of the compressor wiring.

My latest book 12/24 volt Refrigeration Manual covers these systems.
http://www.kollmann-marine.com





(Rick Itenson) wrote in message ...
I have a 12v holding plate unit with a Danfoss D25 compressor. The
compressor will run for a minute or so and then cut out. The air
cooling fan continues running. It will start again and then cut out
again. Over and over. Last week I had a problem with a poor ground and
the whole unit was shutting down (low voltage, beeping ) I fixed
that,(new wiring) there's lots of voltage (no voltage drop) and now I
have the compressor shut down problem. The freon (R12) is good I think
(was frosting up nicely on the weekend). The compressor is not
overheating (it only runs for a minute! I can hold my hand on it for
ever without burning). Is it the control module and is this problem
coincidental or related to the earlier low voltage problem. (the low
voltage problem was intermittent over a week, I used the wire jiggling
method before I finally corrected it by re-wiring). Is it the
compressor? There is no amperage spike when it starts - just the usual
4 amp draw. The unit has run flawlessly for 15 years. I am at the end
of my limited knowledge. Help!


Rick Itenson
La Belle Aurore
Toronto

Three pieces of bad advice in one post, Rod.

1. On small capillary tube refrigerators the frost level is an
excellent indication that refrigerant level is still OK. It is not the
best way to add refrigerant but it will indicate refrigerant loss.
2. These small air cooled systems are not equipped with low Freon or
low pressure switches.
3. The refrigerant level has nothing to do with Rick's problem, as he
reported it. Putting gauges on one of these very small system, can
compound the problem.

I just submitted an article to one of the boating magazines on how the
lack of knowledge about refrigerants and servicing of boat
refrigerators is costing boat owner's big dollars. I have also opened
a new forum on my web site to provide more current information and
help on boat refrigeration problems.







"Rod McInnis" wrote in message ...
"Rick Itenson" wrote in message
...
The freon (R12) is good I think
(was frosting up nicely on the weekend).

It frosting up is not a good indication that the Freon level is okay. Many
refrigeration systems include a shut off switch to protect the compressor in
the event that the Freon level is low. I would recommend having someone
test it with the gauges

Rod