Buying A Bosch Gas Tankless Water Heater As A Replacement

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Choosing a Bosch gas tankless water heater as a replacement makes sense – here’s why:

If you’re in the market for a new water heater to replace an existing hot water tank, you should have a look at a Bosch gas tankless water heater – specifically – the Greentherm 9000 series.

In this line, you get Bosch quality design and construction, a quicker, easier installation, plus – hassle-free operations and maintenance.

For added peace of mind, Bosch also offers a 15 year warranty on the heat exchanger, 5 years on other parts, as well as a 1 year warranty on what Bosch labels “reasonable” labor charges.

Hot Water At the Ready – From A Compact Bosch Gas Tankless Water Heater

What you get with the Bosch tankless water heater is a space saving design that looks every bit as modern and efficient as it actually is. In this brief article, we’ll discuss the top seven models in the Greentherm lineup.

Here Bosch deploys condensing technology to create an super-efficient tankless water heating system that are among the most energy efficient in the industry. All models are Energy Star approved and can produce enough hot water for a minimum of two to three major faucets at the same time.

High-Tech Look and Feel

All of these tankless systems look the same. They all are housed in metal cabinets with cool rounded corners, with a shatterproof glass front. It certainly looks high tech. And all models feature an electronic ignition.

Each one measures approximately 9.75 inches deep by 18.5 inches wide by 31.5 inches high and weighs about 77.5 pounds – so they’re not exactly light by any means. There’s also a digital display feature on each water heater, making it a breeze to set it up to your liking once installed.

Wi-Fi Enabled – With Compatible App

Not only do you get the digital display, but you can also connect your Bosch gas tankless water heater to any smart device via Wi-Fi and monitor your water heater from the palm of your hand, which is quite convenient.

Simply download and activate the free Greentherm 9000 mobile app and you can remotely control your water heater. This means that you can adjust the water temperature, activate the recirculation pump (on those models that include the built-in pump) and monitor the usage of your hot water to give you a clearer picture of your household’s daily needs.

Having the ability to monitor your water heater from your smart phone is super convenient. It is particularly helpful when your tankless water heater is installed in an out-of-the-way place, like in a basement utility room.

Have It Installed For You

It is always recommended that with a whole house water heater, that you use a certified professional for installation. It’s also a must should you ever have a warranty claim. The problem for the handy do-it-yourselfer is it looks awful tempting to just go ahead and install it yourself.

But for the warranty to be valid, your Bosch heater must be installed by trained and certified installer, service agency, or gas supplier.

If you install it yourself – something plenty of DIY types are certainly capable of doing – your warranty may be deemed null and void. In our opinion, it’s not worth the risk. Hire a competent professional and enjoy the peace of mind in knowing the job is done right and you’re fully protected.

Professional Installers Love These 

Pros who install water heaters all day long tend to love the Bosch Greentherm 9000 series because they’re fairly quick and easy to install – particularly when they’re replacing an existing water heater unit – whether it’s a hot water tank or a tankless system.

What makes it a favorite among pro installers are the readily accessible water connections on top of each unit, plus the integrated drain ports that are built-in, so isolation valves are not required. What this boils down to is that these Bosch tankless water heaters take less time to install correctly than other competing brands and models.

There’s also a built-in sensor that automatically calibrates water heating operations, which makes switching to a tankless water heater that much more painless for homeowners.

Take Your Pick Of The Greentherm 9000 Series

Somewhere on this list is the ideal Bosch gas tankless water heater system for you. It doesn’t really matter whether you’re using this in a house, townhouse, condo, or large commercial project. There’s a Bosch Greentherm water heater that will do the job.

What Every One Of The Top 5 Bosch Tankless Water Heaters Offers

  • Water connections on top of the unit for easier tank replacement
  • Auto-tuning for better performance automatically
  • Integrated flush ports (these drain ports on the bottom eliminate the need for expensive isolation valves)
  • Space-saving compact design
  • High-resolution color LCD user interface
  • Ultra efficiency
  • Wi-Fi accessibility (with free downloadable app from Bosch)
  • Integrated freeze protection
  • Stainless steel heat exchanger (This helps minimize scale buildup and since stainless steel lasts longer than copper, you can rest assured that you’re getting a water heater that is well-built with quality components, so it should last a long time)

Indoor and Outdoor Versions

Some are meant to be installed outdoors and the others inside. A few of them boast an integrated pump for hot water recirculation and instant delivery instead of the usual delay you get with most tankless water heaters on the market.

Indoor models can be converted from natural gas (NG) into liquid propane (LPG). Right out of the box, they are all made to be connected to natural gas lines. But if you prefer liquid propane – conversions can be done on indoor models, according to the manufacturer.

Numerous options exist for venting, making most installations somewhat straightforward and relatively simple.

Our Top Picks – The Best Bosch Gas Tankless Water Heaters

Bosch T-9800 SE 199k BTU Residential Outdoor Tankless Water Heater

By: Bosch Model: 7736503727

Here’s another one of Bosch’s outdoor models. If your existing hot water heater is located outside, this could be an ideal replacement for you.

Wi-Fi connection (Optional)

Maximum water flow at a 35 degree increase = 11.2 GPM

Maximum water flow at a 45 degree increase = 8.7 GPM

Maximum water flow at a 55 degree increase = 7.2 GPM

Maximum water flow at a 75 degree increase = 5.2 GPM

Maximum water flow at a 90 degree increase = 4.4 GPM

Bosch T-9900 SE 160k BTU Residential Indoor Tankless Water Heater

By: Bosch Model: 7736503730

This popular model is an indoor unit that also comes with an integrated recirculation pump.

Wi-Fi connection (Optional)

This ensures that water that’s trapped in the line does NOT flow as ice cold water. Recirculation means it get reheated fast.

Maximum water flow at a 35 degree increase = 9.0 GPM

Maximum water flow at a 45 degree increase = 7.0 GPM

Maximum water flow at a 55 degree increase = 5.8 GPM

Maximum water flow at a 75 degree increase = 4.2 GPM

Maximum water flow at a 90 degree increase = 3.5 GPM

Bosch T-9900 SE 199k BTU Residential Indoor Tankless Water Heater

Bosch Model: 7736503731

This indoor-only version of tankless water heater also boasts a recirculation pump, to help reheat water that gets trapped in the line between uses.

Wi-Fi connection is Optional

Maximum water flow at a 35 degree increase = 11.2 GPM

Maximum water flow at a 45 degree increase = 8.7 GPM

Maximum water flow at a 55 degree increase = 7.2 GPM

Maximum water flow at a 75 degree increase = 5.2 GPM

Maximum water flow at a 90 degree increase = 4.4 GPM

Bosch T-9900i SE 199k BTU Residential Indoor Tankless Water Heater

Bosch Model: 7736503732

Here’s the final Bosch tankless water heater from the Greentherm 900 line that we heartily recommend.

It too features a recirculation pump, to ensure that any water that should be hot out of the tap is as hot as you like it.  With 99% thermal efficiency, very little heat is lost.

Built-in WiFi Connected

Maximum water flow at a 35 degree increase = 11.2 GPM

Maximum water flow at a 45 degree increase = 8.7 GPM

Indoor Bosch Gas Tankless Water Heater T-9900i SE 199k BTU Model 7736503732 AllWaterProducts,com

Get the Best of the Best – Click Here

Maximum water flow at a 55 degree increase = 7.2 GPM

Maximum water flow at a 75 degree increase = 5.2 GPM

Maximum water flow at a 90 degree increase = 4.4 GPM

Reliability and Stability

Most people who choose a Bosch tankless water heater are looking for something that’s more reliable than their current tank-type water heater. Of course, energy efficiency is another key component, since the more efficient any device is, the less it costs your to operate over the long term.

Easy To Accommodate

Since these Greentherm 9000 units are tankless systems, you can fit them in pretty well anywhere. Most people who are replacing an aging tank are amazed at how little space these tankless models occupy – and the new found space they acquire.

Small – But Sophisticated

For such a small piece of equipment (relative to any hot water tank) these Bosch water heaters seem much more modern and sophisticated. And most people are surprised at how straightforward the setup is it, In fact you’ll probably find that it’s as simple as connecting the old type of tank heater.

If there is a more time-consuming element to the installation, it typically is running the intake and exhaust lines properly. But if these are already in place, you’re golden.

Customers are thrilled at the instant hot water that they get at the tap – hot water that seems to flow endlessly. They also appreciate that there’s not a lot of settings that need to be adjusted once you get your water temperature set the way you like it. It’s basically a hassle-free operation.

And the real beauty of these whole home systems is that you can use multiple taps at once. Just how many and how fast and furious they flow depends on the model and how much you need to increase the water temperature from the source to the tap. Each model is a little different in this regard. So select the one that best meets your needs.

Feature Rich At A Reasonable Price

A Bosch gas tankless water heater offers a lot of useful features built-in, and they do so at a competitive price. Primarily designed for residential applications, this series can deliver hot water up to 140°F at a 9 gallon per minute rate of flow with a 35°F rising temperature required.

The bottom line is this: The Bosch gas tankless water heater represents good value for the buyer. All models run on 120 volts (besides the gas) and can therefore be plugged into any normal household outlet. Although, you should always have a dedicated outlet for your hot water heater. This simple plug-in set-up helps avoid the challenges involved with any sort of direct wiring.

These models offer up to a maximum of 11 gallons per minute of hot water at a temperature increase of 35 degrees. They vary between 160,000 BTU in 199,000 BTU. Thermal efficiency measures a stellar 99%. What makes these Bosch gas tankless water heaters so awesome is that they are whole-house water heating systems. So they are designed to provide plenty of hot water on demand – without any interruptions.

All seven models can deliver water at 100 to  140°F. Temperature settings – whether via the digital display or your smart phone – are accurate and easy to read.

Each Bosch tankless also comes equipped with automatic tuning and freeze protection – so you can enjoy optimal performance over the long haul, no matter what the weather happens to be where you live.

Another interesting point is that the average life expectancy on these tankless water heaters is about 20 years- give or take. That’s notably higher than most tank-based water heaters can provide.

How Much Flow Do You Need?

When factoring in how much water flow you’ll actually need (and therefore which model to choose) consider the following typical scenarios:

Bathroom Sink Faucet: 1 to 1.5 Gallons Per Minute

Kitchen Faucet: 2 to 3 Gallons Per Minute

Shower: 1.5 to 3 Gallons Per Minute

Dishwasher: 2 to 4 Gallons Per Minute

Washing Machine: 3 to 5 Gallons Per Minute

How Can You Measure Your Existing Water Flow?

To determine the water flow rate you may require moving forward, it’s important to measure the rate of water flow you currently have at each fixture. If you plan on using multiple faucets simultaneously, you need to add the flow from each, giving you a total flow. This number will indicate the maximum flow rate required in your new water heater.

To do so, record the fill times at each faucet using a large half- gallon or gallon container. You’ll need to know the volume to get an accurate measurement. For example, if you can fill a 1 gallon jug in 30 seconds, you’re getting a flow rate at that specific faucet of 2 gallons per minute.

Check The Ground Water Temperature In Your Area

It’s also important to know the average groundwater temperature in your area. Please refer to the map below. This will help you determine how much of a increase in water temperature is required. The greater the difference between the ground (or inlet) water temperature water and the temperature you desire in the shower – the more energy necessary to heat it and the lower the volume that flows.

Approximate Ground Water Temperatures U.S.A. EPA

The Verdict

In our opinion, any one of these Bosch gas tankless water heaters would be an excellent solution for providing abundant hot water in an energy efficient manner.

For new homes, you’ll be equipped with a quality system from the get-go. And if this is a replacement purchase, you’ll be astounded by the difference it makes.

As a result, you will save not only space but money and  time too – plus the unnecessary stress that can develop when you have a water heater that is less than reliable.

Quick Comparison Table Of The Greentherm 9000 Series

Maximum water flow at a >>>35 degree increase45 degree increase55 degree increase75 degree increase90 degree increase
Bosch T-9800 SE 160k BTU
Model: 7736503726

Residential Outdoor
9.0 GPM7.0 GPM5.8 GPM4.2 GPM3.5 GPM
Bosch T-9800 SE 199k BTU
Model: 7736503727

Residential Outdoor
11.2 GPM8.7 GPM7.2 GPM5.2 GPM4.4 GPM
Bosch T-9900 SE 160k BTU
Model: 7736503730

Residential Indoor
Recirculation pump
9.0 GPM7.0 GPM5.8 GPM4.2 GPM3.5 GPM
Bosch T-9900 SE 199k BTU
Model: 7736503731

Residential Indoor
Recirculation pump
11.2 GPM8.7 GPM7.2 GPM5.2 GPM4.4 GPM
Bosch T-9900i SE
199k BTU
Model: 7736503732

Residential Indoor
Recirculation pump
11.2 GPM8.7 GPM7.2 GPM5.2 GPM4.4 GPM

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