Ice buildup on heat pump condenser
_Stephen_
| Posted in Mechanicals on
I have a Mitsubishi PUZ-HA30NHA5 heat pump. We got our first really good snow yesterday, and some ice has built up on the outdoor unit.
Should I be concerned. I’m in Southern Ontario. Should I have a snow hood?
–Steve
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Replies
You need air circulation through that coil for the unit to operate efficiently. If that ice is from a storm, or roof runoff, then yes, you need something to protect the unit.
If the ice built up on the coil from it running, then your system might be low on refrigerant and you’ll want to have that checked. Make sure the fan on the condenser is working too.
Bill
It's only blocking the front left side of the unit, the entire back, which is the bulk of the coil is still unblocked. I think some snow formed on the top of the unit, and melted over successive defrost, and refroze down the side of the unit, The ice is quite thick, perhaps 5-6 mm.
Is it continuing to do it's normal defrost cycles?
Is it installed consistent with the Cold Climate Installation Guidelines?
http://meus1.mylinkdrive.com/files/Cold_Climate_Installation_Guidelines.pdf
Does it have a pan heater/base heater?
It's going through it's normal defrost cycles just fine, it's just not defrosting this bit of buildup, which is rather on the thick side.
That document is what prompted the question of if I need a heat pump. I've forwarded it to my HVAC contractor, to see what he thinks.
From the photo, it looks like it might just have ingested the snow during the storm. In this case, a snow hood might help. Definitely follow the guidelines Dana posted.
It is definitely a result of the storm. We've had cold humid nights, and no significant buildup, that the defrost cycle didn't deal with.
The photo looks like normal “frost” just before a defrost cycle. Because your coil is colder than the air it is normal for moisture from the air freezes on the coils. The system has sensors to detect this frost and should melt it off from time to time. This should happen before frost affects the heating performance of the unit.
Your unit should be above the ground far enough that snow will not block the air flow.
You may need an optional heater under the unit if the water from defrosting refreezes inside the unit and builds up.
Does water drip off the roof onto the unit? This can be a problem if the sun heats the roof but not the unit, so water drips on the unit and freezes.
Walta
It's rather thick, perhaps nearly 5-6 mm. I think snow built up on top, and melted down the side during defrost.
Sorry - no answer for you but I'm in Kitchener and considering a Zuba or Trane XV19.
I would love to hear how the Zuba has gone for you. I've also found no information about the Zuba for anything but high heat mode and at that the Trane kicks it's ass all the way to -18C. With my calculations I've got the Trane at about $290/winter for heating but the Zuba at $420/winter with it's published high heat mode data.