Condo Water-Source Heat Pumps: Loop, Tower, Association and Permit

How the building water loop works

A water-source heat pump is a heat pump that swaps heat with water instead of with outdoor air. A water-to-air unit has a coil for the air in your rooms and a second connection for water pipes. Oak Ridge National Laboratory wrote a 2008 report sponsored by the Department of Energy. It says systems with a separate heat pump for each building zone, all tied to one two-pipe water loop, began to appear in the early 1960s. It says this arrangement is now commonly called a water-loop heat pump system.

A paper from the University of Alabama describes the same layout. Water-to-air heat pumps sit throughout the building, and a central piping loop connects them all. The paper says the loop is typically held between 60°F and 90°F. A cooling tower removes heat when the loop goes above 90°F, and a boiler adds heat if it falls below 60°F.

Our reading: when your unit cools your rooms, it passes the heat it removed into the loop water. Your neighbors' units do the same, and the tower is what finally sends that heat outdoors. Because the pipes are shared, the loop is building equipment, not just part of one home.

The Oak Ridge report adds a Florida note. It says the first market for water-source heat pumps was southern Florida, where early systems pumped groundwater or canal water through the heat pump and discharged it. A condo loop is different, because the same water circulates in a closed pipe circuit.

What the cooling tower does, and why it is a health topic

The CDC says all cooling towers use the evaporation of water to remove heat and release it into the atmosphere. It lists heat pumps among the equipment that towers cool. A closed-circuit tower has an additional closed loop that keeps the cooling fluid from being exposed to the atmosphere, while an open tower does not. Which kind your building has is a question for the association.

The CDC also treats tower upkeep as a health matter. It says that if Legionella, the bacteria behind Legionnaires' disease, is present, the aerosolized water can spread the bacteria over miles. It names four key factors that affect Legionella growth: sediment and biofilm, temperature, water age, and disinfectant residual.

For tower maintenance the CDC recommends an offline disinfection and cleaning at least annually, and flushing of low-flow pipe runs and dead legs at least weekly. A dead leg is a pipe branch where water sits without moving.

Our reading: this is shared equipment, so it falls to the association and the contractor it hires, not to an individual owner. You can still ask management whether a written water-management plan for the tower exists.

What you control and what the association controls

Florida's condominium law is chapter 718 of the Florida Statutes. Section 718.103 defines the key terms. It says common elements are the portions of the condominium property not included in the units. It says limited common elements are common elements reserved for the use of a certain unit or units, as specified in the declaration. It says a unit is a part of the condominium property subject to exclusive ownership.

Section 718.113(1) sets the starting rule: maintenance of the common elements is the responsibility of the association, except for any maintenance responsibility for limited common elements assigned to the unit owner by the declaration. It adds that the declaration may provide that certain limited common elements shall be maintained by those entitled to use them.

Our reading: the statute sends the question back to your declaration. Depending on how it is written, the heat pump in your unit could count as part of your unit, as a limited common element assigned to you, or as something else. The loop piping and the tower are the kind of equipment a declaration would more likely treat as common elements.

The things almost every owner controls are day-to-day use, such as the thermostat setting, and reporting a problem to management. Everything beyond that depends on your documents.

Why replacement starts with the association

Section 718.113(2)(a) says there shall be no material alteration or substantial additions to the common elements, except in a manner provided in the declaration as originally recorded or as amended. If the declaration does not specify a procedure, the statute says 75 percent of the total voting interests of the association must approve before the work starts. Section 718.113(3) adds that a unit owner shall not do anything within the unit or on the common elements that would adversely affect the safety or soundness of the common elements or association property.

The statute text we read does not say whether swapping one heat pump for another of the same kind is a material alteration. Our reading: a like-for-like swap inside your unit may not be, but moving a pipe connection, drilling through a shared wall or floor, or adding an outdoor unit would touch common elements. Moving to a different system type, such as a ductless mini-split, is a bigger step. See ductless mini-split systems for how those work.

Our reading of the loop's design: a replacement unit has to work with the loop it joins. The Oak Ridge report says the boiler and tower exist to keep water entering the heat pumps within design limits. So ask the association or its engineer for the loop's design temperature range and any approved models before you buy.

Get the association's answer in writing, and ask for its alteration or contractor rules. Associations differ, and some publish a form, a list of approved work hours or an insurance requirement for contractors. If you are unsure what your documents mean, a Florida condominium attorney is the person to ask; this page is not legal advice.

Why a permit is part of replacement

A permit is separate from association approval. Florida Statutes section 553.79(1) says it is unlawful to construct, erect, alter, modify, repair, or demolish any building within the state without first obtaining a permit from the appropriate enforcing agency. The enforcing agency is usually the city or county building department.

Section 553.79(1)(g) says a local government that issues building permits shall exempt an owner of a single-family dwelling, or the owner's contractor, from the permit requirement for some small jobs. It says that exemption does not apply to work on property in a flood hazard area, or to any electrical, plumbing, structural, mechanical, or gas work performed on property containing a single-family dwelling. Our reading: a condo unit is not a single-family dwelling, so that exemption is not a reason to skip the permit. The building department makes the final call, so ask it.

For why permits exist and who normally pulls one, read HVAC permits in Florida. Refrigerant work also calls for a technician holding a federal credential, which the Section 608 guide explains. Some associations ask to see the permit and the contractor's license before work begins, so ask yours.

Systems that look alike in a condo

Not every condo with a shared system has a water loop of this kind. Three look-alikes are covered on their own pages.

An air-source heat pump, with its own outdoor unit, is covered in heat pumps in Florida. That page covers humidity, salt air and flood-zone placement for outdoor units.

A chilled-water system, where a central chiller sends cold water to indoor air handlers or fan coil units, is covered in chiller systems and fan coil units.

A ground-source system, where buried pipe replaces the tower and boiler, is covered in geothermal heating and cooling. The University of Alabama paper notes that burying the loop removes the need to run a boiler or cooling tower.

A quick check is to look for the equipment. A heat pump in a closet or ceiling space with two water pipes, and a tower on the roof or ground, points to a water loop. Our reading: confirm with management or the building's plans, because the same closet can hold a fan coil unit.