DIYbanter - View Single Post - Why does my car ac system keep blowing up?

Ashton Crusher[_2_]

On 15 Oct 2015 20:59:46 -0400, (Scott Dorsey) wrote:

Ashton Crusher wrote:
I put in 80% of the amount of R12 as I'm using 134a. Running it in
the driveway at 2000 rpm I've seen the low side drop to 30 and the
high side go to over 325. I don't see how they could possibly go even
that high, much less to the 400 psi needed to pop the high pressure
valve within 2 minutes after starting with the engine at or near idle
speed.

Anyone got any theories? Too much oil? Too much refrigerant? Not
enough virgins being sacrificed?

Clogged expansion tube. Clogged evaporator.
--scott

Evap was not clogged either time. Doesn't have an expansion tube,
just an orifice tube. I guess that could clog but there is a filter
screen before anything gets to it. Why would it do so immediately
after starting and while idling yet never do so while running down the
highway for hours on end?