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As a Tenant and Owner

Options for Retrofitting an Air Conditioner

An air conditioner provides relief on hot days.
An air conditioner provides relief on hot days. Photo: Getty Images
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June 3, 2020, 10:01 am | Read time: 3 minutes

High temperatures in the summer often lead to the purchase of air conditioners, but the market offers a wide range of options. What should renters choose—and which upgrades are worthwhile for homeowners?

At night, it’s too hot to sleep, and during the day, it’s too warm inside for any movement. If you’re considering buying an air conditioner, you’ll find various options on the market–from portable to permanently installable. What works best for whom?

Installing an Air Conditioner as a Tenant

As a tenant, you can only install certain units–unless the owner agrees. The owner must approve all structural changes to their property. This includes any wall breakthroughs, which would be necessary to connect a permanently installed split unit, explains the Building Climate Association.

Also of interest: How to ventilate properly in the heat

Such a split system has two parts. One is permanently installed indoors and connected by coolant lines to the outdoor unit. These devices are usually permanently installed and not suitable for quick purchases by tenants. However, according to the association, there are a few flexible split units available on the market.

Monoblock Units as an Alternative to Permanently Installed Air Conditioners

The practical alternative for tenants is so-called monoblock units. They can be easily placed wherever cooling is needed. Their warm exhaust air is vented through a tilted window with a hose. The downside: They are louder than split units, less effective, and not as efficient, explains TÜV Rheinland. Because of the tilted window, some warm air from outside always enters the living space.

More on the topic

How to Retrofit an Air Conditioner in the House

You can permanently install a split unit or flexibly set up a monoblock. However, both options typically only cool a limited area. True air conditioning systems for the entire house, like those in large commercial buildings, can be installed or retrofitted in private homes. But this is very costly and therefore uncommon, explains Günther Mertz from the Building Climate Association.

Ventilation systems, which are found in many new buildings and replace manual window opening for air exchange, are also difficult to upgrade with an air conditioning function. The ducts are not designed for the larger air exchange needed for air conditioning. Therefore, this retrofit is not implemented in practice, says Mertz.

Also of interest: Are more expensive energy-saving refrigerators really worth it?

How to Retrofit an Air Conditioner as a Homeowner

Retrofitting a true air conditioning system in a residential area is very costly. According to the association, mobile mono or permanently installed split units are better. But the latter can be problematic, as structural changes cannot be decided by an individual homeowner alone. They are subject to the decision of the homeowners’ association.

The type of approval needed depends on the type of unit and its installation, informs the homeowners’ association Haus & Grund. For example, if the split unit for an apartment is installed on the exterior facade in a way that is highly visible, all co-owners of the homeowners’ association must agree. However, if it is mounted on the wall in a way that not all co-owners can see it, nor can third parties from the street, it does not necessarily require the consent of all (OLG Düsseldorf, 3 Wx 197/06).

A common point of contention is the disturbance caused by the unit’s operating noise. All those affected by the noise must agree (OLG Düsseldorf, Az: 3 Wx 179/09). But Haus & Grund also clarifies: If no owner is affected, the person wishing to install it can demand the consent of the other apartment owners.

This article is a machine translation of the original German version of MYHOMEBOOK and has been reviewed for accuracy and quality by a native speaker. For feedback, please contact us at info@myhomebook.de.

Topics Summer
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