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Trouble-Shooting => Refrigeration => Topic started by: 90grad on September 18, 2005, 06:45:28 am



Title: Cavalier 51 thermostat
Post by: 90grad on September 18, 2005, 06:45:28 am
All,

Had to get a new thermostat when I rewired the Cavalier 51.  This is a non-contact one from Funtronics, which is what Steve recommended.   Where should I put the probe?  I've been moving it around, but the machine is getting too cold before shutting off, and that's with the dial set on 1.  Any thoughts?


Title: Cavalier 51 thermostat
Post by: Jim on September 18, 2005, 08:30:14 am
How about attempting to get the capillary tube as close to the evaporator as possible; especially where the fan can blow across the capillary tube.
Is the capillary tube coiled up to aid in positioning/mounting...?


Title: Cavalier 51 thermostat
Post by: 90grad on September 18, 2005, 11:34:57 am
I mounted the new stat where the old one was.  The old one was a contact-type.  The cap tube is coiled up, so I have a lot to play with.  I can try to move it to the bottom of the evaporator coil, which is where the cold air blows out.  I'll route the tube down there and see what happens.


Title: Cavalier 51 thermostat
Post by: 90grad on September 18, 2005, 02:15:53 pm
Update....

I unwound some of the tube and moved it in the airflow directly off the evaporator.  In a Cavalier 51, the stat sits up by the evaporator fan.  The fan blows down and the air output is at the bottom of the cabinet (about 2 feet from the stat location).  So, I routed the tube down there.  The thermostat is set on about three-quarters and the machine, according to my thermometer, is about 32.  So, I'd still like to move the tube to another location so I could get a more precise adjustment.  Should I try to get it on the evaporator?  I'm open for ideas.


Title: Cavalier 51 thermostat
Post by: 90grad on September 20, 2005, 05:15:44 am
Update and question...

1. The machine cools to about 34 with the thermostat set on nearly 1, so I know I have to move the sensing tube around some to find the right spot.

2. I have a thermomoter placed inside the door so I can do quick temperature checks.  I've noticed the compressor will cycle on/off every 2-4 minutes and the temperature difference isn't that great when it does (still in the low 30s).  So, do I need to fine-tune the thermostat or do I have other issues?  I know there are two little screws on the stat to adjust when the thing starts and stops, but which is which?  Help!


Title: Cavalier 51 thermostat
Post by: Jim on September 20, 2005, 09:36:52 am
Wayne,

Place your thermometer inside the bottle vend door on one of the bottle chutes for easy/quick access.
I'm not sure which screw is which on the thermostat; did it come with instructions?
Adjusting the cut-in/cut-out screws can get tricky since you have no reference point once you start rotating the screws... Getting it back to original is difficult, to me anyway... Now I just leave them alone.
Can you coil the cap tube back up carefully and perhaps relocate the whole thermostat so the complete cap tube is exposed to the coolest air off the evaporator?


Title: Cavalier 51 thermostat
Post by: 90grad on September 20, 2005, 09:49:11 am
Jim,

I just got off the phone with Eric from Global Compressors.  Man, he's a good guy.  He told me how to adjust the cut-in and cut out stuff.  We also discussed placement of the cap tube from the stat.  His instructions were:

1. Place it as close to the evap coil as possible.  He advised to put it at the top of the evap coil, so I don't get the coldest air (better indication of overall temp).

2. I have a thermometer in the ammo belt right inside the door.  I told him I was at 1 on the stat and was getting to 32 degrees.  He said to first adjust both screws, which will allow me to dial a higher number.  Then, to adjust the delta T, I turn the cut-in screw a little more, which will prevent the machine from cycling so much.  

I will see what happens tonight.  Thanks for the help!