Fujitsu Split Pressure Release?
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I have 2 wall mounted splits connected to a Fujitsu multi; both have been running nonstop all summer and cooling well. The smaller 7k will cycle in the bedroom, but before I hear the refrigerant make its way up the pipes, it sounds like some sort of pressure release from the outside unit. Similar to when heating and it goes in to defrost, not as loud. It seems to happen every time that unit is about to fire up.
The other 12k is the main source of cooling and is running 24/7, no issues at all. No icing up or anything like that outside. Before I call a tech in just wanted to see if anyone has any ideas?
Thanks,
Kevin
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Replies
Kevin,
I'm sorry that I can't help you with any useful suggestions. I'm posing this comment to bring your question closer to the top of the list -- maybe a GBA reader will see your question and offer some advice.
I am not sure how the Fujitsu are programmed but it is not uncommon for the program in high SEER systems to start the compressor and cool the indoor coil before staring the fan and cooling the air.
The first time I heard mine the plumber and I were near the air handler and far enough away from the condenser we could not hear it. The sound of refrigerant moving in the pipes had both of us convinced water was leaking somewhere.
It should sound a lot like a defrost cycle because it is doing the same thing. A defrost cycle is when the system reverses and takes heat from the house to warm the outdoor coils and melt the frost.