Noisey Indoor Unit

[rude]

hi have a high wall split that is making noise through the coil. As in i can hear the gas going through the coil and the customer isnt too happy about it as he wants the unit to be quiet. I listened for it and found it too be louder than usual.

So my question is what can cause this?

indoor unit is roughly 10m below condensing unit
system is on 410a and is an invertor

my first guess would be a gas issue, but the indoor coil isnt icing up or anything

any ideas?

thanx in advance

[Don78]

how long has this system been in operation? Where is the filter drier located on the liquid line? U can sometimes reduce noise at the evaporator coil by installing the filter drier near the evaporator coil.

[rude]

apparently about 3 months, but has only been running on heating and worked fine. but the customer noticed the noise on cooling.

interconnecting pipe doesnt have a drier from what i can see

[nike123]

apparently about 3 months, but has only been running on heating and worked fine. but the customer noticed the noise on cooling.

interconnecting pipe doesnt have a drier from what i can see

Does the noise frequency related to sped of inverter or it is related to speed of fan motor?
Try to play with fan speed and set point settings to establish that, if you are not sure.

[stefs_cruiser]

Any model numbers please?

Possible causes are.
Flare connections inside the building behind the unit, instead of straight out the wall.
Unit may be under charged.
Pipes could be kinked, often seen when they go up through the cavity or top plate, as the bending spring often starts about 3" behind the unit.
Is the noise there all the time, or only after starting up?

[rude]

Does the noise frequency related to sped of inverter or it is related to speed of fan motor?
Try to play with fan speed and set point settings to establish that, if you are not sure.

I couldnt access condensing unit but i had the unit set to 16 degrees, indoor temp 22, outdoor temp 30

the noise seems to always be there but does get louder at times, ffan speed doesnt seem to affect it



Any model numbers please?

Possible causes are.
Flare connections inside the building behind the unit, instead of straight out the wall.
Unit may be under charged.
Pipes could be kinked, often seen when they go up through the cavity or top plate, as the bending spring often starts about 3" behind the unit.
Is the noise there all the time, or only after starting up?

flare connections are behind the unit and not straight out.

i cant see that any pipes are kinked, but the pipes do go through a wall cavity

the noise is there all the time

Unit is a panasonic e24fkr, i just read the service manual and looks like the unit is only good for 10m pipe run. My estimation is about 10m for the pipe run soo i might just add about 20g - 40g of refrigerant and see how that goes

[nike123]

So, noise you hear is gurgling noise?

[rude]

So, noise you hear is gurgling noise?
sort of...

its more like a pssssshhh sound tho if that makes sence

[back2space]

SOunds like a fizzing sound, its just the noise of the refrigerant flowing i guess.

IN heating mode this wont be heard as that sound takes place in the outside unit.

[stefs_cruiser]

CS/CU-E24FKR Panasonic unit is good for a 30m pipe run, and a max elevation of 20m
However they are only precharged for a 10m
so if it is over 10 meters, you will need to add 30grams per metre. (over the 10)

In this case, the flare connections inside will create some noise.

If I understand this correctly, the pipes go behind the unit accross, flare connection are there as well, and then it goes via the wall cavity?

I suspect the noise may be just from the connections, and may be normal.

What is normal to one person, may not be acceptable to the next though...

Good luck

[rude]

i managed to see where the condensor was put and it was over 10m, sucked in 30g of gas and noise was gone

thanx all for your help