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Multifamily Apartment Water Heater Guide

Commercial Tankless Water Heaters For Apartments 101

Multi-family apartments present one of the most challenging types of commercial properties when it comes to water heating requirements. While sizes vary, some apartment properties can have hundreds of units with multiple residents in each. Each unit, usually, would have several hot water outlets including baths, showers, sinks, dishwashers and washing machines, among others.

Given such high-demand requirements, perfecting the hot water needs at multi-family properties can be complex. Errors can lead to residents not always getting an adequate hot water supply. In a residential setting, such a scenario can lead to apartments being forced to overhaul their water heating system, leading to unnecessary costs. Moreover, choosing a substandard water heater can lead to constant maintenance headaches, high operational costs, and inefficient energy usage.

This guide will begin by outlining some of the factors to consider when thinking of water heating for multi-family apartments. Followed by that, we will consider the tankless choice for multi-family apartments and understand the pros and cons of stepping away from the traditionally-favored storage tanks. We will explain the process of sizing a water heater for multi-family apartments correctly, followed by looking at a case study to see whether tankless water heaters can meet the demands of multi-family properties.

Table of Contents

Factors to Consider When Choosing a Water Heating System for Multifamily Apartments

There are three key factors which are crucial when it comes to selecting a water heater for multifamily properties:


1. High Volume

Multi-family apartment properties have a really high volume of hot water needs. In most cases, each unit has a hot water shower and hot water outlets in bathroom and kitchen sinks. Apart from that, several properties have an in-unit washer as well as a dishwasher. Most of these applications, being residential, witness constant usage at a high volume. Think of a standard family of four taking showers once/twice a day, and using the washer and dishwasher multiple times in a week.

2. Instant Hot Water

Hot water users in multi-family properties being residential demand instantaneous hot water. Significant delays in the delivery of hot water is unacceptable for residential uses. Several states also have ordinances in place that allow tenants the right to withhold rent if they do not get a reasonably adequate supply of hot water

3. Sporadic Usage Patterns

While it is true that there are some notable patterns in the usage of hot water, every resident behaves differently. For example, while it can be surmised that most residents will take a shower in the morning, the timings can vary greatly. Some residents might prefer taking hot water showers at other times of the day while others may have an uneven pattern. The sporadic nature of hot water usage is perhaps better exhibited in the usage of dishwashers/washers/dryers. A multifamily property’s water heating system needs to be capable of operating effectively with such frequently sporadic demands of hot water. 

4. Extreme Demands

Counter to the point above, there are still a few times during the day when a multi-family apartment might face an overall high volume of hot water demand. For instance, in the mornings, multiple apartments might have their hot water showers running. This means that a multifamily property’s water heating system would need to be able to deliver hot water simultaneously to all of the outlets at the set termperature.

5. Energy Efficiency

Residents are not fans of paying consistently high energy bills. Hence, it is imperative for multi-family apartment properties to be energy efficient. Water heating accounts for about 20% of a home’s energy usage (source). Hence, a water heating system that consumes the least amount of energy is a necessity to avoid high energy bills all-year-round.

Water Heater Temperature Costs

6. Downtime

Ineffectively designed water heating systems are prone to frequent maintenance breaks. This can be a result of failures, spare parts that need to be changed, leakages in the storage tank, or other factors. Such breaks can cause downtime which would lead to a multifamily property not having enough hot water. Downtime can lead to major inconveniences for the residents as it would mean lack of hot showers or proper dishwashing/clothes-washing.

Are Tankless Water Heaters Recommended For Multifamily Apartment Properties?

Apartment Tankless Water Heaters for Instant Hot Water: As tankless water heaters don’t store water, their distinguishing principle is their ability to heat water instantly. BTUs/hr is a common unit used to measure the capacity of tankless water heaters to heat water in a particular time frame. When sized correclty, a strong, commercial-grade tankless water heater can satisfactorily meet any hot water demand.

Apartment Tankless Water Heaters for Energy Efficiency: Since a tankless water heater does not need to keep a large quantity of water constantly hot, it is more energy efficient than a tank-style water heater. This means lower energy bills for the residents as well significant space savings due to the elimination of storage tanks. 

Apartment Tankless Water Heaters for Hassle-Free Maintenance and Reducing Downtime: Since tankless water heaters do not need to have a storage tank, the risk of downtime due to leakages is drastically reduced. However, ease of other forms of maintenance largely depends on the manufacturer and the particular model installed in a multifamily facility.

The Intellihot Choice for Multifamily Apartment Properties

Intellihot’s products are innovatively designed with the needs of the end consumer in mind. When it comes to multifamily properties, our iQ Floor series is the most popular choice due to the high power of these products. In fact, our iQ3001, iQ2001 and iQ1501 are the world’s first, second, and third strongest tankless water heaters respectively.

Intellihot For High Volume, Instant Hot Water

Intellihot products use its patented Dynamic Storage technology to check and maintain the set temperature 20 times every second. Our products, being some of the world’s strongest tankless water heaters, are designed with the goal of providing large amounts of hot water instantly. The iQ3001, being our strongest water heater, provides 3 million BTUs/hr. Moreover, the unit can be wirelessly cascaded with another one for added power. 

Intellihot for Redundancy

iQ3001 web

Our heavy-duty water heaters like the iQ Floor Series have multiple stainless-steel heat exchangers, each with their dedicated control. Such a design adds incredible redundancy as a breakdown in one of the heat exchangers does not equate to the entire system being broken down, leading to virtually zero downtime. Moreover, our units are cascaded in a masterless setting. Hence, there is no downtime associated with the master water heater breaking down: something that is often observed in units that are cascaded in a master setting fashion.

Intellihot for Hassle-Free Maintenance

Intellihot’s innovative water heaters are designed to have the bare minimum number of spare parts. This not only helps us streamline our supply chain, but it also helps our consumers reduce the frequency of maintenance due to the changing of spare parts. Moreover, our products’ touchscreen display shows the health of each spare part, allowing facility managers to order spare parts in advance so that any maintenance needed can be scheduled at a convenient time. The device’s dashboard can also be accessed remotely from anywhere using our telliCare app.

Intellihot for Energy-Efficiency

Intellihot’s products come with a high degree of thermal efficiency ratings. This means that their energy output is closer to the energy input than most competitors. Moreover, they rely on AI-powered algorithms to closely monitor energy usage to optimize it further. The Electron series, for instance, uses its algorithm to utilize off-peak electricity, thereby reducing energy bills.

How Can I Size A Tankless Water Heater Correctly For My Apartment Property? Are Tankless Water Heaters Effective for Multifamily Properties?

Understanding the right size of tankless water heater for your multifamily apartment property can be complicated if you do not possess some technical knowledge, similar to tank-styled water heaters. You would want to avoid a tankless water heater that cannot handle your specific load. On the other hand, purchasing a water heater that is significantly more powerful would result in excess costs and wasted space since more powerful water heaters tend to take up more space.

You can use our water heater sizing calculator to get an accurate snapshot of your hot water requirements. You will get an instant, personalized report containing multiple options of Intellihot’s products that can serve your multifamily property’s needs.

All you need to do is a fill a basic form with information about your multifamily property’s physical space like the number of rooms, showers, and other hot water outlets. Our accurate calculator will generate a guaranteed and detailed report that is personalized to your query. If our estimates are wrong, we will pay for any additional equipment. Below are some snapshots of our detailed sizing results. 

Can Tankless Water Heaters Handle High Volume Loads in Apartments? A Case Study

So, it is evident now that tankless water heaters have some significant advantages over their traditional tank-style counterparts. However, multifamily property owners and managers are often hesitant about tankless water heaters being able to meet all the hot water demands of a large site. Moreover, the fact that Intellihot’s tankless units are small enough to fit in a standard elevator makes property owners doubt the power of tankless water heaters like our iQ series. 

Several multifamily apartment property owners who have successfully adopted tankless water heaters echo our belief that tankless water heaters are ideal for large sites. 

Let’s look at a case study which should help quell any remaining concerns.

One of the tallest residential buildings in Chicago, 340 on the Park, was facing various water heating failures due to their outdated system. 

After sizing the 344-unit property, their 2000 gallon storage tank and two accompanying 2 million BTUs/hr water heaters were replaced with just four iQ1001s.These units were enough to meet the entire property’s hot water needs. They also resulted in increased efficiency, huge amounts of space savings, operating cost reductions, hassle-free maintenance and zero downtime. 

Designed for large-volume, commercial applications, these high input units slash capital costs by up to 50%, and decrease operational costs by up to 40%.

“We have been very pleased with the installation and performance of the system and proud to be at the forefront of demonstrating an energy-efficiency breakthrough in the building community. Any building that has a domestic hot water boiler capital project in the future should be considering Intellihot,” commented building manager, Amy Eickhoff. 


Before: 340 On the Park's outdated and inefficient tank-style water heating system
After: Four Intellihot iQ1501s enough to handle the 344-unit property's hot water needs

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