My window a/c hisses lightly?

Question

Have a Maytag window a/c, 6500 btu, usage about 20 months, it's been in storage for a year after the first 18 months of use, though. Noticed a hissing that comes and goes, very light, with no apparent loss in performance.

Qs: what could be the source(s) of this hissing?

If it's freon leaking (remember there is no loss in performance so far), can it be toxic/hazardous to me in any way?

If it's freon leaking, how could I notice it (by sight/smell/etc.) without necessarily waiting for a performance drop?

Any other pointers would be appreciated; I'll also call the maytag people tomorrow.

Please only respond if you have the knowledge; random guesses are appreciated, but unfortunately won't result in me giving credit for them.

Thanks.

Answer 1

I'm not familiar with this particular model, but I'm guessing it's okay.  You know how a spray can gets cold when you use it?  (shaving cream, hair spray, etc.)

Anyhow, your airconditioner uses the same concept to cool the air.  Inside the system is a tiny valve the size of a pinhole.  As the refrigerant sprays through it, you will hear a hissing noise.  It's just part of normal operation.  

Without actually hearing it myself, I can't know for sure.  But I'm 90% sure that's what's going on.  Don't worry.

Answer 2

For the most part Freon can't harm your health.  It could only be a problem if you inhaled so much you got no oxygen but that would take inhaling deeply right off the tubing. Plus a leak would be gone rather fast.

The only time it can be dangerous is if the freon is heated with an open flame. Then it can create chlorine gas. But that is still difficult in an open room or if the fan is running. Technicians welding with a torch need to be careful about that, but you don't.

You are safe, and yes, it is likely a normal sound. If it was leaking enough to hiss the refrigerant would have been gone and it would have stopped working in little time.

Answer 3

Do you notice it when the unit shuts off, if so its just the pressure inside equalizing.