Data Aire DAAU-3034

[atufano]

Anyone here have experience with Data Air units? I have 4 units that I'm having trouble getting my condensing units to dial in correctly now that we are in the shoulder seasons going into winter. I spoke with Data Air and they have put me in the right direction, but I am still going off on lp and hp faults. I dialed it into SC 8-10 and SH 8-15. but it kicked out on hp later in the day. DA gave me guide lines to set up the condensing units, but nothing definite. They come from the factory set up with fan 1@65 2@75 3@80 with a 5-10 diff for warmer weather, but now we're in milder weather it's kicking off.

The last contractor low charged the units and had the condensers cycle at 1@30 2@40 and 3@50 which now in the cooler weather, the units pop on LP. But it also puts the P66 to spin the fan slow and burns out motors. I have a small book of motor replacements from the last contractor.

I have the units pretty squared away, except for the condensers. So if anyone has some tips or a procedure to dial these things in, would be great. DA does not have one, or if they do, they're not telling me.

I have been using a SH and SC meter on each circuit as I charge so I don't go over on one or under on the other. My one concern is that these units have been so screwed up, I hope the txv isn't hunting which will never let me properly charge these.

[ascj]

How many condenser fans? 4

All the DA condensers I have worked on have a P66 on fan 1, pressure control on fan 2, and temperature control on the rest of the fans.

I'll assume this doesn't run a flooded receiver?

[atufano]

They have P66 on fan 1 and temperature controls for fans 2-4. No flooded receiver. I have 27 lieberts, all have receivers and I usually don't have problems with them. Just make sure the liquid is between the glasses...

[blueridge2]

With a Data Aire system the sub-cooling needs to be correctly set for proper fan operation. The sub-cooling needs to be between 8 and 10 degrees when using a P-66 or P-266 fan speed control. Unless the system is under a very light load, there will be flashing in the sightglass before the TXV when properly charged with refrigerant.

The fan setting are as follows with a P-66 fan speed control, fan 1= fan speed control, fan 2 = 65 degrees, fan 3 = 75 degrees, fan 4 = 85 degrees, fan 5 = 50 degrees. The setting are for the fan cut in, the cut out should be set as close as possible to the cut in. This will be around 5 to 8 degrees.

The compressor superheat for the CRAC unit is 8 to 15 degrees (compressors in the air handler). If the unit has condensing units (compressors in the condenser unit) the superheat target is 20 degrees.

The above settings will work all year around with out any seasonal adjustments to the temperature controls.

If you have more questions, please contact the Data Aire Service Department.

[buford]

The one's i have put in we run the indoor fans all the way to max amp's,put on fixed size pulley on the fan motor once the max amp's are set. The odu #1 fan on the p-66#2 fan put on a pressure sw or 2 sw's if dual circ and leave the temp stats for the other fan's.The last data aire i installed the od cond came with the black ecm cond fan's on it and it ran great. the only thing was there was no adjustment on them to set.The one's with the p-66 like to eat the fan motors that they control.I have found the indoor unit's need all the air you can give them and it would be nice to have freeze stats on them for the low load and or low return temp's they might encounter.

[atmosphere]

Are you using ball bearing motors on the p-66 fans?

[atufano]

With a Data Aire system the sub-cooling needs to be correctly set for proper fan operation. The sub-cooling needs to be between 8 and 10 degrees when using a P-66 or P-266 fan speed control. Unless the system is under a very light load, there will be flashing in the sightglass before the TXV when properly charged with refrigerant.

I have set all the units up with a 8-10 degree superheat and there is little flashing in the sight glass. Both running 1 unit and then running both units.

The fan setting are as follows with a P-66 fan speed control, fan 1= fan speed control, fan 2 = 65 degrees, fan 3 = 75 degrees, fan 4 = 85 degrees, fan 5 = 50 degrees. The setting are for the fan cut in, the cut out should be set as close as possible to the cut in. This will be around 5 to 8 degrees.

I have the p66 set up with an additional 1/2 turn adjustment. fan 2 = 40, fan 3=50, fan 4=60 and I have the cut outs at 10deg. Should I set up 2=65, 3=75 and 4=50?

The compressor superheat for the CRAC unit is 8 to 15 degrees (compressors in the air handler). If the unit has condensing units (compressors in the condenser unit) the superheat target is 20 degrees.

This is where I am having an issue. The superheat on some units is dead on. On others, the txv is hunting either from low load or a bad valve. But I cannot see that many valves go bad all at once.

The above settings will work all year around with out any seasonal adjustments to the temperature controls.

If you have more questions, please contact the Data Aire Service Department.

[/quote]
I have been. I'm the guy from Albany NY with 4 of these things.
Thanks. I'll be in touch with you guys this week. I'm getting close, it's just nuisance calls now. You can PM me if you don't want to discuss this on this forum.