Trane capacity control MOD0182

[chlrtec]

I have very little expieriance w/ the old Black Classic Panels. I'm having trouble with a cvhe045 overshooting the supply setpoint. It will cycle off on reset, due to low return water temp. Is there a resistance vs. temp. chart so I can check the lvg chw temp. sensor.
Also, I just increased oil vent pipe size to 1 1/8 and installed solenoid vlv. When I went to start up machine I noticed the lvg chw temp. problem. While tending to that problem the machine lost oil.

[chillrdude]

I've got a temp chart for that I will have to find it and post it this evening, as for your oil loss problem did it lose oil at startup or had it run awhile. What kind of load is on your machine and what was your tower water temp, was the vent solenoid energized at start up?

[freonrick]

the solenoid valve you installed is a normally open valve?

[acjourneyman]

Swap the leaving water sensor with one of the other water sensors and see if that helps, sounds like you didn't have the solenoid wired correctly and it didn't energize at start up, make sure when it starts that the solenoid is energized.

[chlrtec]

Found my oil loss problem. Too, embarassed to explain But I have a since of humor so feel free to guess. My problem with the cap. cntrl. mod is still overshooting the set piont. I didnt have a temp. vs. resistance chart for the SEN0132 (lvg. chw). I just bought a new one and compared. I'm getting the same readings . This tells me my sensor is okay. What else can I check or is the mod0182 bad. This mod. was just installed 4 mths ago. But not by me.

[Chomper]

Originally posted by chlrtec
I have very little expieriance w/ the old Black Classic Panels. I'm having trouble with a cvhe045 overshooting the supply setpoint. It will cycle off on reset, due to low return water temp. Is there a resistance vs. temp. chart so I can check the lvg chw temp. sensor.
Also, I just increased oil vent pipe size to 1 1/8 and installed solenoid vlv. When I went to start up machine I noticed the lvg chw temp. problem. While tending to that problem the machine lost oil.

Did you also install a delay timer with the solenoid? This not a generic valve as Fric eluded to.
There are no other sensors to swap with. Low return water temp is a load condition and TYPICALLY has little to do with the leaving sensor. Although ya never know with a small loop.

[chlrtec]

Installed N.O. valve wired into a 100 second timer wired into start signal. This is all fine, valve energized at start up, for 100 seconds. Keep guessing!
As for the mod. problem. When I say overshooting, I mean the lvg chw temp will drop down to 38 degrees and cycle off when the return water gets to 45, as it should. my set point on the mod is 45. and yes the sensor is in the lvg chw pipe. Chiller has corrct charge. Refrigerant temp will stay within 5 degreess of lvg water

[acjourneyman]

Is the chiller unloading or are the vanes staying open when it drops the temp to 38 degrees.It has been so long since I have worked on a black panel controller that it is hard to remember it now.

[absrbrtek]

Is there a load on this machine? Are the guidevanes closing properly? Flow rates correct?

[maxster]

that temp control "knob" might be out of position seen it adjusted to match the setpoint of loading/unloading..or NULLED and reinstalled on new start-ups.

[chlrtec]

flows are good. Vanes continue to open up, like its trying to maintane this low temp.

[acjourneyman]

Sounds like the knob was put on wrong, adjust up to maintain 45deg and reset the knob, it is only a set screw.

[carolinachill]

Check load load and unload relays inside the Mod. You can swap the relays, as they use different contacts.

[chlrtec]

Thanks for all the help. It turns out that the sensor was bad. Even thow I compared its resistance with the old one at a high and low temp. But Im still not convinced. I hate problems like that, where you solve the problem but your standing back scratching your head.Thinking how did that happen. The only other thing I did was, I put a piece of insulation inside the sensor well. Because it fit so loosely. Maybe, ambient temps were affecting its performance. There is the CHW pump right behind the lvg chw pipe. The pump motor has a fan on the tail end with a shroud coming over the motor, forcing hot air in the sensor direction. Anyways, the chiller is running fine now and already reclaing additional oil I put in to get it on line. I piped in a second eductor to get any oil out of the refrigerant. Well, thanks again for all the help.

[ga1279]

You mention blowing hot air accross an exposed sensor, that should not happen as the sensor fits far enough down the factory supplied well so ambient or in this case fan cooling should not effect it. You also need to use heat paste between the sensor and well. It sounds like you aren't using the correct well if the fit is that loose. The module depending on revision may not have the load or unload relays 0890, if it's the last rev. it has DIP switches for temperature span load and unload delay. See which one you have and get the correct service lit from Trane. Are you also using a temperature return reset sensor, if not is the module switches set-up for return water reset and looking for a missing sensor, that will cause overshoot.
Good Luck, ga1279