A homeowner can install their own heat pump. Heat Pump and Central Air Conditioning systems have always been a little mysterious to most homeowners. They are complex devices and can be a little intimidating.
However, if you are handy and up for a challenge, you can install a heat pump. There are a few things to consider before you start.
- A new electrical circuit may be required.
- Yard space will be required for the outdoor unit.
- A new install will require cutting holes in your house.
- Charging the unit with freon may be an issue.
I have successfully installed two ductless (mini-split) heat pumps in the past few years. I have also helped install ducted systems. From my experience, the mini-split system is more suited for the DIYer.
There is one brand of ductless heat pump that is designed specifically for the DIYer. There are also DC-powered units that run directly off of solar and a battery bank. We will look at DIY aspects later in the article.
Ducted Central Air vs Ductless Mini-Split
Ducted heating and cooling have been the norm in the US for decades. Today the systems are seen as bulky and not always very efficient.
Over the past twenty years, ductless systems have taken over a large part of the HVAC market in the US. Greater versatility and efficiency have made ductless systems a standard in the US.
How Ducted Systems Work.
The outdoor unit consists of a compressor, a heat exchange coil, and a fan. The compressor pumps heated or cooled freon into the house. The indoor unit is a heat exchange coil in the home’s ducts.
The ducted fan blows air through the coil. The air picks up the heat or cool from the coil and carries it into the house. The waste heat or cool is circulated through a second copper line back to the outdoor unit where it is transferred to the atmosphere.
Ducted System Pros
- Whole House system.
- Uses existing ductwork.
- Can provide air filtration if so equipped.
Ducted System Cons
- Indoor fans can be noisy.
- Distribution of heat or cool can be uneven.
- Interior fan can require considerable power.
- Heat and cool can be lost through the duct material.
How a Ductless Heat Pump Works.
The basic function of the outdoor unit is the same as the ducted system. Mini-split outdoor units tend to be smaller due to the efficiency of the system.
The cooled or heated freon travels through the line-set directly into the room. An exchange coil and fan are housed in the indoor wall unit. The fan blows room air through the coil and the conditioned air spreads into the room.
The heated or cooled freon exits the house via a second copper line and the waste heat or cool is exhausted by the outdoor unit.
Ductless system Pros
- No ductwork interface.
- Comes with integrated inside and outside units.
- More effective zoned heating and cooling.
- Indoor fan units are extremely quiet.
Ductless system Cons
- Indoor unit may be intrusive to some home owners.
- Condensate drain line from indoor unit may be tricky.
- Initial cost may be a little more to cover same area as ducted system.
Steps To Install A Heat Pump
Once you’ve decided on a system the work begins. The operation of both styles is basically the same. Indoor unit location is the main difference. The basic steps, in no particular order, are:
- Locate and place outdoor unit.
- Locate and install indoor unit.
- Route and install freon line-set and condensate lines.
- Provide power.
Every job is different. Both styles have a few different components that dictate the order that tasks are done. The order does not matter much. The main thing is to read your manual, plan, and take your time.
Where to install a heat pump?
The location of the outdoor unit is important for two reasons. There must be room for the unit to move air. The manual will specify a minimum clearance.
More room is better. The other important factor is access to the indoor unit. In both styles, a freon line-set must be run from the outdoor to the indoor unit.
Ease of access makes the job much less difficult. The cooling function in both styles will create condensate that needs to be drained from the indoor unit. Determine these locations before you begin.
Considerations when choosing locations.
- Is there enough room for air flow?
- Can the freon lines reach from indoor unit to outdoor unit?
- Can power be run to that location?
- Is there a place for condensate drain?
- Will location be in the way of other activity?
Once locations and routes are determined you can install those items. For a ducted system, you install a heat exchange coil in the duct of the forced air system.
You can also install the line-set at this time. A ductless system’s indoor unit will be located on an interior wall. The line-set will run through the wall to the outdoor unit.
Connecting the Power
Both heat pump styles will require a power circuit for the outdoor unit. Installing a new circuit may require a permit. In a ducted system, the indoor blower will have its own power supply.
There will be a signal wire that needs to run from the thermostat in the house to the outdoor unit. In ductless systems, the power for the indoor unit is part of the freon line-set. Refer to the manual for circuit requirements.
Do not shortchange the electrical circuit. An insufficient circuit can result in poor unit performance even an electrical fire. Even if you do not need a permit, follow electrical codes.
Hook Up Your Heat Pump
Once the units are installed and power is in place it is time to connect coolant lines. A freon line-set is simple to connect. But, do so with care. Crossed threads or loose connections can cause leaks.
Here I will mention the one true DIY mini-split heat pump I am aware of. Mr.Cool DIY mini-split units come pre-charged with freon.
When you hook up your lines, you are ready to heat and cool! With other brands, you may need a licensed HVAC Technician to fill your unit with freon. It can be done by the homeowner but requires some fairly expensive equipment and knowledge to be done properly.
Installing a heat pump is a big job. It takes a serious DIYer to do it successfully. Some steps may require a professional. Electrical additions may require a permit.
Even if you only take on the installation portions and leave the hook up to the pros, you will save some cash and achieve a sense of satisfaction in your hard work.