Water leak on a daikin wall unit

[marc5180]

I got called out to a wall unit in a office the other day that keeps leaking.
One of the other engineers had already been out to it and thought he had fixed it but he hadn't.

I cant remember the model of the wall unit but its 5 or 6 years old on r407c and about a 5kw.

The coil is an upside down "V" shape and after stripping the unit down to get at the coil i could see water was dripping from the top of the coil (the point of the"V") and onto the spinning fan, which was causing water droplets to fall down and drip out of the unit where the air off comes out.

I checked the unit was level, cleaned the coil throughly (even though it was clean), re-fixed the unit to the wall as it was hanging off by 1/2 inch, tried turning the fan speed down and checked the fan wasn't blocked but nothing seemed to work.

The water from the coil should run into the tray either side of the coil but the top of the coil just drips vertically down onto the fan.

Has anyone come across this before?

[Andy AC]

Hello Marc, is the unit in a greasy atmosphere? Might be sticking to the grease.
Had a problem with a couple of wall mount de-hums that hadn't been serviced for a few years - the water would drip off the coil and sit as a blob in the drip tray. It would not disperse, the blob would get bigger and bigger until it made its way out over the side of the tray, rather than down the drain - weird. That was something to do with static and dust, when cleaned problem went away.

Andy

[al]

Marc

Have seen this on some Hitachi's of the same vintage, we found leaks on the units, once a fresh charge was weighed in problem disappeared, we've also had similar on some Sanyo 407c cassettes.

al

[rude]

Has the unit always done this or just recently? Has any work been done on the unit?

Id say for starters to weigh in a new charge and go from there and see if that helps.

[marc5180]

Hello Marc, is the unit in a greasy atmosphere? Might be sticking to the grease.
Had a problem with a couple of wall mount de-hums that hadn't been serviced for a few years - the water would drip off the coil and sit as a blob in the drip tray. It would not disperse, the blob would get bigger and bigger until it made its way out over the side of the tray, rather than down the drain - weird. That was something to do with static and dust, when cleaned problem went away.

Andy

Hi Andy, the room is a post room with one server in.
I've cleaned the coil throughly so i'm sure it isn't a dirty coil.

Marc

Have seen this on some Hitachi's of the same vintage, we found leaks on the units, once a fresh charge was weighed in problem disappeared, we've also had similar on some Sanyo 407c cassettes.

al

About the only thing i haven't checked is the charge.
I'll weigh a fresh charge in when i go back.

Has the unit always done this or just recently? Has any work been done on the unit?

Id say for starters to weigh in a new charge and go from there and see if that helps.

The unit has only just started doing it, over the past few weeks and no work has been done on it apart from maintenance.

I'll weigh a fresh charge in and go from there.

Thanks for your help guys.

[regcooldude]

check for a hair line crack in the plastic upper pan. i've had this a few times