HVAC recharging / Freon type / anyone done this at home?

[wiztecy]

HVAC recharging / Freon (Refrigerant) type / anyone done this at home?

It was 44f out today and when I kicked on the heater/ac to defrost the windows I had a vds error, I'm set to debug mode, that indicated that the hvac pressure was low. It appeared 3 times and went away. Appears this may be a debug message only when logging verbosity is turned up. My hvac pressure is 1.8- 2.3 bar (from the vms) which seems low. Anyone know what value this should be?

Would like to recharge the HVAC system myself and have the high and low side charger for the refrigerant. Does anyone know the refrigerant type the roadsters take? And do we need to add any lubrication to the system like a traditional type of AC system in an ICE car?

Now that its warmed up to over 70+ degrees I don't get the low pressure of the HVAC system, something tells me its right on the borderline of needing a recharge.

Thanks


-Update-

The HVAC refrigerant pressure has increased with the rise in ambient temperature, its now at 2.8 bar.
Also when you pop the front hood, on the passenger side of the Roadster there's a sticker that shows the Refrigerant type which specifies R134A.

Since its not complaining as the ambient temp has risen, I don't think I'll add any lubricant. However I'm still very curious if we need it and what type if calls for.

 

[Pantera Dude]

I'm sure it must use R134 like all other late model cars. (I'm not aware of any manufacturer using anything else)? It is probably marked somewhere on the system. I'm pretty sure it works like any other automotive AC system, so I would treat it the same. I'm no expert but I have charged my own systems before, though not on my roadster.

- - - Updated - - -

The owner's manual may have some info?

 

[dhrivnak]

It is R134 as my system is marked. I too see the low pressure warning when cold outside. I think it is a "feature" and pressure WILL change with temperature.

 

[Doug_G]

When my Ranger recharged my freon, there was a gizmo inside the car that froze during the process. He tried again later on and it worked properly. Freezing up resulted in an undercharge situation, which resulted in constant "HVAC Compressor Overtemp" messages in the log. (Mine came from the factory that way.)

 

[wiztecy]

It is R134 as my system is marked. I too see the low pressure warning when cold outside. I think it is a "feature" and pressure WILL change with temperature.

Thanks all!

So my guess is that we've lost some refrigerant over the years through the rubber seals/connections and need to top it off. I didn't have this error last year when the temps dropped. My guess is that the recharge process is just like any other HVAC system / recharge, that we need to run the HVAC system while recharging and monitor the high/low pressure values shooting for the green.

I'm not seeing any issues in cooling when I do the cool-down process off of 240v when I get home from my commute. No other errors and the system is fine. Thanks Doug for that info, I'll check and make sure nothing 'locks up' when I do a recharge.