CTC high discharge

[DaButcher]

I have seen Carrier Ultras with high pressure fault many times through the years, and the cause is low ***** level. Never really understood why the processor sets this fault. Anyone care to explain?

[absolute-zero]

I have seen Carrier Ultras with high pressure fault many times through the years, and the cause is low ***** level. Never really understood why the processor sets this fault. Anyone care to explain?

Sorry cant help myself, but i know the answer to this as well.

The suction pressure transducer on the suction line reads the suction pressure, soon as the summit controller sees a, vacuum HG pressure reading for more than 30 seconds, it will energize the rear compressor unloader in efforts to see suction pressure come up, then it will enrgize the front, if still remains in vacuum, the the unit will display high pressure and turn into a shutdown conditon.

TK has a couple units that do a similiar same thing that confuses most, for an example the code 109 in multi-temp SR units states high head pressure, from the transducer, if you ever noticed when a system is out of refrigerant or near out of refrigerant this code will generate. but the description of the code confuses most.

Code 89 ETV electronic throttle valve problem similiar thing, techs auto matically go to the ETV expecting to find a problem, only to find the micro never saw a reaction to suction pressure changes when testing the ETV, mostly because the unit was low or out of refrigerant.

Code 10 on SR truck units with open drive scrolls same thing, the high pressure cutout, low pressure cut out and higfh compressor tem cut out are all wired in series, and feeds signal to the coil side of the run relay. If any one of those switches opens it throws code 10, and if cleared by driver and the switch remains open, the remainder code will be 35.

This one stumped me for about an hour one day before i wisened up and lookedt a schematic.

Regards A-Z

[thermo prince]

Great stuff a-z, keep this up and you will make " moderator' grade yet or better still, Webram may offer you a partnership ? co-directorship ?etc YUK YUK

best regards
T-P

[absolute-zero]

Great stuff a-z, keep this up and you will make " moderator' grade yet or better still, Webram may offer you a partnership ? co-directorship ?etc YUK YUK

best regards
T-P

T-P

"Thanks buddy" Glad to help whenever I can.

I dont think they will be considering making me modertor or co-partener considering my "tedious" track record,,, anytime soon. YUK YUK.

If the offer does ever come across, I think I may require RE moderator training before I could consider it.


Regards A-Z

[Brian_UK]

I dont think they will be considering making me modertor or co-partener considering my "tedious" track record,,, anytime soon. YUK YUK.

Regards A-Z

Still at it then

[absolute-zero]

Still at it then

Nah I dont sweat the small stuff.

Regards A-Z

[DaButcher]

Code 89 ETV electronic throttle valve problem similiar thing, techs auto matically go to the ETV expecting to find a problem, only to find the micro never saw a reaction to suction pressure changes when testing the ETV, mostly because the unit was low or out of refrigerant.

Code 10 on SR truck units with open drive scrolls same thing, the high pressure cutout, low pressure cut out and higfh compressor tem cut out are all wired in series, and feeds signal to the coil side of the run relay. If any one of those switches opens it throws code 10, and if cleared by driver and the switch remains open, the remainder code will be 35.
Regards A-Z

Ya, after the first experience with code 89, I assume it is low ***** level.

I don't service many truck units, code 10 on SB units is low battery volts sometimes.

[absolute-zero]

Ya, after the first experience with code 89, I assume it is low ***** level.

I don't service many truck units, code 10 on SB units is low battery volts sometimes.

I have not found that to be common here, but in those rare occasions the code 10 was accompanied by a alrm code 61 or 35.

regards a-z

[abbsnowman]

Another one that often catches rookies on the CTC's is the oil pressure alarm that is generated by a faulty alternator. If this alarm shows on start up, check for power on the D pos. or "orange wire" before the unit starts.
By the way, Absolute zero I am glad to meet you! Everyone should check out your site. Are you an outcast too?

[absolute-zero]

Another one that often catches rookies on the CTC's is the oil pressure alarm that is generated by a faulty alternator. If this alarm shows on start up, check for power on the D pos. or "orange wire" before the unit starts.
By the way, Absolute zero I am glad to meet you! Everyone should check out your site. Are you an outcast too?

Greetings abbsnowman,
Good to meet you too. I have several post and threads here on that tech-tip you posted. Its a good one, and does catch lots of techs by the short hairs.

Site????What Site????? Outcast??? I dont know what your talking about.

But seriously I do like to hang out here so please dont spam or make any mention of advertising of the sort.



Best Regards A-Z

[SteinarN]

I have seen Carrier Ultras with high pressure fault many times through the years, and the cause is low ***** level. Never really understood why the processor sets this fault. Anyone care to explain?

I have no experience with Ultras, but on Maximas is the HP and LP switch conected in series. It gives an HP alarm whenever one of them tripps.

[absolute-zero]

I have no experience with Ultras, but on Maximas is the HP and LP switch conected in series. It gives an HP alarm whenever one of them tripps.

I have not had the pleasures of ever seeing or servicing a maxima,,,, Am i missing much??????

A-Z

[swissreefer]

SteinarN is absolute right.
maxlp.JPG

[absolute-zero]

SteinarN is absolute right.
maxlp.JPG

Not debating if wrong or right, just curiouse of the other differnces in service relation, between maxima and Ultra models..

A-Z

[SteinarN]

I have not had the pleasures of ever seeing or servicing a maxima,,,, Am i missing much??????

A-Z

Nope.

Well, its an ok unit, at least the monotemp version. The multitemp version has more flaws and an unbelievable unreliable 1 phase 230V generator. The zone 2 and 3 has only electric heating. Its ok for defrost, but here in cold Norway its inadequate to heating in cold ambient. Especially when you consider that the unit must be running in high speed to generate voltage by the electic motor (which acts as an asyncroneous generator in high speed to supply voltage to the heating elements in zone 2 and 3) and the heat lockout function at zone 1 at termostat setting below -12 degres C. When the driver has frozen goods in zone one and fresh in lets say zone 2, then the unit go crazy in high speed trying to heat zone 2 while at same time high speed cool only at zone 1! Before you know it it's -35 degres C in zone 1. Easy to maintain +8 in zone 2 then. Espesially when its -20 degres C outside!

However they realized the idiotic function of heat lockout and came up with a new software which was configurable to disable that function 2 years ago.


And it's intendend to trailers, not semis.

[absolute-zero]

Nope.

Well, its an ok unit, at least the monotemp version. The multitemp version has more flaws and an unbelievable unreliable 1 phase 230V generator. The zone 2 and 3 has only electric heating. Its ok for defrost, but here in cold Norway its inadequate to heating in cold ambient. Especially when you consider that the unit must be running in high speed to generate voltage by the electic motor (which acts as an asyncroneous generator in high speed to supply voltage to the heating elements in zone 2 and 3) and the heat lockout function at zone 1 at termostat setting below -12 degres C. When the driver has frozen goods in zone one and fresh in lets say zone 2, then the unit go crazy in high speed trying to heat zone 2 while at same time high speed cool only at zone 1! Before you know it it's -35 degres C in zone 1. Easy to maintain +8 in zone 2 then. Espesially when its -20 degres C outside!

However they realized the idiotic function of heat lockout and came up with a new software which was configurable to disable that function 2 years ago.


And it's intendend to trailers, not semis.

It sounds allot like the CTC genesis TM 900-TM1000 in comparison

Thanks A-Z

[SteinarN]

It sounds allot like the CTC genesis TM 900-TM1000 in comparison

Thanks A-Z

Probably the same unit then. An older version of Maxima multitemp was named TM 800 i think.