[zootjeff]

We put in a heatpump at a house at the coast. It has a metal cabinet and it has only been 6 years and the cabinet is rusting like crazy. The heatpump is used for heating and cooling of the house but the marine air brings salt with it that is corroding the top fan grate and every where the air hole vents were perforated (sharp corners of stamped sheet metal don't take much paint..)

The unit is under a covered deck so it doesn't get much in the way of sunlight. Would like to find a solution that allows us to keep the indoor air-handler coil.
Geothermal would be nice but would rather explore marine hardened air-source solutions first.

1. Do any manufacturers make marine grade air-source heat pump outdoor units?
2. Anyone else have this problem?

 

[roughneck]

Yes, manufacturers make coastal rated units. Exactly what they are called differs from brand to brand.
You said this unit is under a deck. Is this a top discharge unit? How much space between the top of the unit and the deck?

 

[zootjeff]

Yes, manufacturers make coastal rated units. Exactly what they are called differs from brand to brand.
You said this unit is under a deck. Is this a top discharge unit? How much space between the top of the unit and the deck?

Second story deck, about 5 feet of clearance. What do they do to make them coastal?

 

[roughneck]

5’ above a top discharge unit is not adequate. You’ll need to remove the deck, move the unit or swap to a horizontal discharge outdoor unit.
The coastal units have a coating on the coil and usually a more substantial paint used on non-coil surfaces.
It should be noted that, generally speaking, units near salt water just don’t last as long even when ordered for coastal duty.
If you unit were installed properly at least rainwater would wash it off from time to time.
But it’s a combination of an improper installation and salt water causing your problems.

 

[zootjeff]

The manufacturer installation manual says 60” of clearance is all that is required. Where are you getting your data and what number would you be happy with for adequate clearance?

 

[roughneck]

What manufacturer and model is this?
Did you mean to say 60”?
I’ve never known a manufacturer to be ok with such tight space for airflow.

 

[zootjeff]

What manufacturer and model is this?
Did you mean to say 60”?
I’ve never known a manufacturer to be ok with such tight space for airflow.

Goodman. I don't know why the quote got turned into a special character code. This is a goodman GSZ140421 outdoor unit, it says explicitly this in the manual:



Installation Clearances
Special consideration must be given to location of the condensing unit(s) in regard to structures, obstructions, other units,
and any/all other factors that may interfere with air circulation.
Where possible, the top of the unit should be completely unobstructed; however, if vertical conditions require placement beneath an obstruction there should be a minimum of 60
inches between the top of the unit and the obstruction(s).
The specified dimensions meet requirements for air circulation
only. Consult all appropriate regulatory codes prior to determining final clearances.

 

[zootjeff]

https://www.acwholesalers.com/manuals/GSSZInstall.pdf

But I'm looking at replacing it anyway. Still really interested if someone can provide a link to marine hardened unit or a part number.

 

[roughneck]

https://www.carrier.com/residential/en/us/products/air-conditioners/24anb7--c/

Here’s one model from carrier. I’ll try to look up more later with more time.
What size is this deck above the unit?

 

[coolair111]

You can buy special unit made for the marine areas that are corrosion resistant.