Should I Raise My Air Conditioner Off The Ground?


Air conditioners and heat pumps can live longer and run quieter by being supported by risers or pump ups. Risers allow the units to drain and helps to reduce some vibration. Heat pump snow legs should be tall enough to keep a heat pump above average snow fall.

What is A Heat Pump Snow Leg?

Snow legs, risers, or pump ups, they are the same. You can even make a frame of angle iron or buy these plastic risers. I’ve even seen units raised up on bricks or blocks. Just doesn’t look as cool or stop any vibrations.

Literally hidden from sight and unknown to 99% of all homeowners are the tiny drain holes at the bottom of your heat pump or air conditioner. When your outdoor unit is installed directly on the pad those tiny drain holes become even smaller and less likely to drain.

Looking down into a heat pump with the top off

Especially if the inside of your unit is full of rotting leaves or other debris that seems to just fall into these units because they have a big hole on they’re top lid.

The end result is an early death for the unit, Not tomorrow, but sooner than if the installation were done properly. Air conditioners can benefit from being raised slightly above the pad, but heat pumps need that lift to drain during there winter defrost cycles.

You have to realize that when a heat pump is cooling your home in summer, the cold coil is the coil at the furnace. When that heat pump is heating your home in winter that cold coil is the coil in the outdoor unit.

The outdoor ambient is pulled through that coil and the air temperature is dropped approximately 15 degrees. Just put your hand over the top when it in heat mode. When those outdoor temperatures drop that outdoor coil becomes an ice maker.

Defrost cycles occur during winter operation of heat pumps. You may have noticed if you have a heat pump that when outdoor temperatures get down and somewhat below the 40 degree Fahrenheit range, the outdoor coils begin to develop frost on the surface of the coils.

If the defrost control is not timing the defrost correctly like the unit above, or the sensors have failed, then that frost will begin to develop into a block of ice. Other things can contribute to ice forming at the bottom of an outdoor unit, such as a low or improper refrigerant charge.

Expected snow level is a great indicator of how high a heat pump should be raised above it’s pad. These heat pump riser legs are fixed at 6 inches. Although you can buy different heights though suppliers like Amazon.

The fan inside your outdoor heat pump is meant to move air through the coils. The coils are the aluminum finned part of the unit that surround the outside from top to bottom. Sometimes covered by a louvered steel surround that you sort of have to get up close to actually see the coil behind.

In harsh winter conditions, snow and ice can accumulate up over the bottom of the unit and begin to block the air flow. Raising the unit up over what snow level that may fall on average in your area. During those 100 year snow falls you need to get out and shovel it away.

Don’t rely on the fact that everytime the unit goes into defrost that it will melt away the snow. That snow becomes ice in a deep enough freeze. You can use warm water to get rid of what gets ahead of your snow and ice removal. Even hose water is warm enough to do some melting.

Never use in tools to break away the ice if it does thicken and cover your unit. Those coils are fragile and you can puncture the copper tubing and create an extremely expensive service call to say the least. Now your on emergency heat and your electric meter is spinning out of control.

If you want to know how to defrost your heat pump in winter, read this, I wrote a complete article cover that defrost issue.

The Power Of Ice Against Your Heat Pump

When galvanized and copper pipes freeze, the freezing water inside the pipe expands and can burst the pipe. Newer products like PEX tubing has the ability to expand with the freezing water and will be less likely to break and leak, but it can.

So it’s not water inside the refrigeration pipe of a heat pumps coil, it’s Freon, then what’s freezing pipes got to do with a heat pump. Ice is a very powerful force. Not only will it burst water pipes from the inside, but it will crush refrigeration pipes from the outside.

crushed refrigeration pipe

When ice forms around these copper refrigeration lines it has no where to go but to crush the copper tubing and restrict the flow of refrigerant inside the line. As you can see by the image above it also has destroyed the aluminum fins around the tubing.

The end result is often that leaks form in the copper and all Freon is lost to the atmosphere.

Installing Or Replacing A Heat Pump Pad And Risers

It’s a whole lot easier to install a new level pad with snow legs at the time of the original installation. But, it can be done after the fact.

It’s a one man do it yourself project. Their are some precautions. When adding pad and risers to an existing heat pump, extreme care needs to be taken not to create a leak at the refrigeration lines that enter the house from the unit.

If those lines are a couple feet long or more you have a good chance. Best to get a service tech to give you an opinion or even hire one to get it done.

But like I said it can be done and it’s not a huge project if done the right way. I gathered up a couple of 2 by’s and some blocks. With a little patience and some ingenuity you can make your heat pump last a few more years.

Place the lumber under the unit first. Raising it slightly, just a little bit at a time. Continue to go around the unit with blocks going up one block at time while keeping an eye on that refrigeration line that it doesn’t brake. Copper is fairly flexible. Just be careful.

Using 2 by’s that are long enough to give some leverage.

Level and replace a pad and add risers. Shorter risers will do if you don’t think you can get it high enough.

Additional Benefits Of Having Your Heat Pump Or Air Conditioner Elevated

The one thing I really like about these plastic pump ups is the little pieces of tar like material stuck to the top and bottom of the risers. It give the unit a solid footing to the pad and does sort of quiets down any vibrations.

You would think by looking at a unit raised up about 6 inches that it would be a little shaky, but they end up quite stable, as long as the pad is firm to the ground.

It’s a very little thing, but when you consider the alternative of setting a unit directly on that gritty pad it’s a great advantage for units set near neighbors windows or your own window and living areas.

When the freezing weather comes you can be sure that the water is draining away much better that it would if allowed to just gather around the bottom of your unit.

Goodman heat pump

My customer who owns the heat pump in the image above likes to capture the water in small pans. Don’t know if I can agree with that process, but it makes him happy. Hard to beat a happy customer, who by the way is always right. And if he’s not right, he’s still my customer.

I like putting air conditioners on 3″ risers. Like I said it dampens the noise and helps keep the unit clean. You can hose off under the unit and it’s not sitting down on that scratchy pad and turning to rust prematurely.

You might think it’s just an air conditioner with a metal base and what would it hurt to just set it right on the pad. If you would have removed as many of these units as I have and looked at the rust at the base because the water never was able to dry out between the base of the unit and the pad, then you’d choose to use risers.

Since you’ve read this far, why not travel just a bit further and scope out a couple of my favorite heating and cooling products and tools.

Thank you for reading my article. I hope the information has led to your ability to make good decisions in either working on or discovering how to solve problems in your home HVAC equipment. These are affiliate links, so if you do decide to use any of them I do earn a commission. In all honesty they are products that I would use in my own home or the homes of my friends and family.

Fireplace remotes by Skytech Remote Control Products . My wife loves this and it probably took all of 30 minutes to install. Replace that wall switch or thermostat for your gas fireplace. Easy installation and instructions. In fact I wrote an article that covers the job pretty thoroughly I think.

Honeywell Thermostats. My favorite two Honeywell stats are the T6 Pro and the 8000 Pro series but their is a bunch to select from besides those two models. You can select WiFi that has the capability of operating your system from your smart phone no mater where you are. Honeywell tech support for homeowners is the best out there. Call them if you need at 800-468-1502 or comment below if you have questions.

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Chad Peterson

Chad Peterson is near 40 year veteran of the HVAC industry. "I like to explain heating and air conditioning problems in a way the average home owner can understand. "

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