Caiman

[Operator27]

Hello all,

Reaching out to this group hoping for answers or how to be steered in the right direction. A few years back my Sheriff’s Office obtained a BAE Systems Caiman through the DRMO program. It has recently been placed into service for our agency’s SWAT team. However we have run into an issue with the HVAC system. The front (dash) blower works but is not blowing cold (supposedly it was today during a training exercise. The rear system isn’t blowing whatsoever. Any assistance in repairing this issue would be appreciated or Atleast where we should go or contact to have it fixed. We are minutes away from WPAFB and are also close to a guard base. Thanks all for your help.

 

[GeneralDisorder]

Well - the cab AC in the Caiman is the same as any other FMTV. If it's not blowing cold then it's just a standard AC system driven by a Sanden compressor off the CAT C7 engine. It has high pressure and low pressure switches to prevent the compressor from engaging if the system is too low on R134 or the fans aren't running and the condenser gets too hot, etc. Make sure the fan disconnect switch wasn't inadvertently turned off (upper left yellow rocker switch on the dash). But the first check would be to put a manifold set on it and check system pressure - the compressor won't even turn on if the system is low on refrigerant. If that's the case it has a leak and that will need to be found and repaired.

The rear system I'm not familiar with - I'm guessing it's possibly some form of Red Dot 24v AC system - regardless it's probably going to use the same R134 as the truck AC and if it's not blowing air at all the first thing to determine is if the system has power - because typically the blower will work even if the AC compressor isn't engaged..... I would be looking for where the system draws power and checking fuses, etc.

That's my guess anyway. I suppose the rear system could be running off a secondary compressor on the engine - I haven't looked at one. But still the HVAC fan should run regardless and that's definitely 24v so start with that.

 

[Operator27]

Well - the cab AC in the Caiman is the same as any other FMTV. If it's not blowing cold then it's just a standard AC system driven by a Sanden compressor off the CAT C7 engine. It has high pressure and low pressure switches to prevent the compressor from engaging if the system is too low on R134 or the fans aren't running and the condenser gets too hot, etc. Make sure the fan disconnect switch wasn't inadvertently turned off (upper left yellow rocker switch on the dash). But the first check would be to put a manifold set on it and check system pressure - the compressor won't even turn on if the system is low on refrigerant. If that's the case it has a leak and that will need to be found and repaired.

The rear system I'm not familiar with - I'm guessing it's possibly some form of Red Dot 24v AC system - regardless it's probably going to use the same R134 as the truck AC and if it's not blowing air at all the first thing to determine is if the system has power - because typically the blower will work even if the AC compressor isn't engaged..... I would be looking for where the system draws power and checking fuses, etc.

That's my guess anyway. I suppose the rear system could be running off a secondary compressor on the engine - I haven't looked at one. But still the HVAC fan should run regardless and that's definitely 24v so start with that.

So I was able to get a look at what’s going on today. The front is blowing and the air is somewhat cold, it will be recharged sometime in the coming weeks. The back however is not working. How should we go about diagnosing if the switch has power or not for the rear system. The rear system is made by Real Time Time Labratories LLC and it’s an LSS Box. Obviously the blower and compressor could be fried, the switch could or couldn’t have power. Also where should we look to check for blown fuses for replacement apparently a bunch were replaced some time ago that were shot.

 

[coachgeo]

So I was able to get a look at what’s going on today. The front is blowing and the air is somewhat cold, it will be recharged sometime in the coming weeks. The back however is not working. How should we go about diagnosing if the switch has power or not for the rear system. The rear system is made by Real Time Time Labratories LLC and it’s an LSS Box. Obviously the blower and compressor could be fried, the switch could or couldn’t have power. Also where should we look to check for blown fuses for replacement apparently a bunch were replaced some time ago that were shot.

Am just down the road from ya.... but am a better searcher of information than am a mechanic. Honestly wish opposit. Anyway.... this might help you get answers on the rear system

Real Time Labs

As to the front system.. any big rig shop worth its salt should be able to advise you. Like others said.. its nothing different in concept than any other vehicle AC...

 

[GeneralDisorder]

I will go through my manuals again and see if there is anything leaping out at me that's relevant but I am not locating a Caiman TM in my collection. I would suggest that you start with a few phone calls to either the DLA directly, or to your Ohio LESO state coordinators. Someone at some level can get you the relevant TM's for this equipment.

State Coordinator List

www.dla.mil

Although Real Time Labs likely created the system, it was BAE that integrated it into the chassis so they are not likely to be of much assistance. The best bet is to go through the same official channel that you procured the unit from in the first place. They provide training and assistance in these matters.

 

[Operator27]

So I actually received a call back from Real Time Labs and spoke with a representative that was over the product line. He said parts are scarce but he would try to see if there was anything they could do and get back with me…it’s been two weeks. I then contacted several members at the Ohio LESO office and have had no Lucy. Anyone have any other suggestions. The guy at Real Time Labs mentioned other agencies have had this issue and they’ve somehow replaced the rear LSS HVAC system with another system. Thanks

 

[Operator27]

Alright so finally had some time today to mess with the system since manufacturer of rear ac system never called back. The switch to the rear unit now has power but the fan or compressor in the back do not turn on. I made sure the power cable to the switch was tight and the on light illuminated. Hasn’t done that since we had it. Is the fan and compressor in the rear system relatively fixable by a qualified hvac or commercial technician? Pictures attached for reference. Thanks

 

[coachgeo]

Alright so finally had some time today to mess with the system since manufacturer of rear ac system never called back. The switch to the rear unit now has power but the fan or compressor in the back do not turn on. I made sure the power cable to the switch was tight and the on light illuminated. Hasn’t done that since we had it. Is the fan and compressor in the rear system relatively fixable by a qualified hvac or commercial technician? Pictures attached for reference. Thanks

I would bet that AC only works when the engine is running... did you have the engine started and idling?

 

[Operator27]

I would bet that AC only works when the engine is running... did you have the engine started and idling?

Truck was on and idling, front A/C system was also on as I believe I saw in the TM where the rear system won’t turn on unless front one is.

 

[coachgeo]

Truck was on and idling, front A/C system was also on as I believe I saw in the TM where the rear system won’t turn on unless front one is.

hmmm... so how does it get a signal to tell it the front is on?? and is that signal happening... and if it is...... is it reaching the rear ac?? or is the rear signal reiver thingamabob no longer reading signals? Assume it a simple relay.. if font AC has power it trips a relay allowing rear controls to work. .. might be somewhere in that ??