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Bosch 520 HN NG Tankless Water Heater, Indoor Use


Bosch 520 HN NG Tankless Water Heater, Indoor Use

We apologize that this product is not for sale at this time. You may enjoy similar products from the Natural Gas Tankless Water Heaters or Tankless Water Heaters categories or the Bosch brand.
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We apologize that this product is not for sale at this time. You may enjoy similar products from the Natural Gas Tankless Water Heaters or Tankless Water Heaters categories or the Bosch brand.

Bosch 520 HN NG Tankless Water Heater, Indoor Use

The Therm 520 HN incorporates an evolutionary hydro-power ignition system which allows this tankless water heater to work without a standing pilot, grid connection or battery! A small turbine inside the water heater uses the energy from the flowing water to ignite the burner. The modulating gas valve then maintains a constant temperature at varying flow rates. This innovative technology, patented by Bosch, makes this an ideal product for installations without access to electricity or regions prone to inclement weather and power outages.

Bosch 520 HN NG Tankless Water Heater, Indoor Use Features:
• Patented Hydro-power ignition requires no electricity
• 80% thermal efficiency
• 117,000 BTU maximum input
• 5.3 gallons per minute capacity at 35F degree rise
• Endless hot water for up to 2 applications at a time
• Minimum activation flow rate of 0.6 gallons per minute
• High to low temperature control
• Vents with galvanized B vent - natural draft
• Built for durability and serviceability with 15-year warranty and 20+ year life expectancy
• Available in NG and LP models

Bosch 520 HN NG Tankless Water Heater, Indoor Use Specifications:
• Condensing/Non-Condensing: Non-Condensing
• Application: Residential
• Max Input (BTU): 117,000
• Min Input (BTU): 30,735
• Capacity at 35 DegreesF Rise (gpm): 5.2
• Capacity at 55 DegreesF Rise (gpm): 3.4
• Intelligent Cascading: No
• Min Flow Rate: 0.6 gpm
• Thermal Efficiency: 80%
• Installation Options: Indoor
• Dimensions (w x h x d): 181/2" x 363/4" x 101/2"
• Weight (lbs.): 35
• Inlet Connection: 1/2" NPT
• Outlet Connection: 1/2" NPT
• Gas Connection: 3/4" NPT
• Max Water Pressure: 150 psi
• Min Water Pressure: 30 psi
• Min NG Presure: 5.7" WC
• Venting Options: Galvanized B-Vent
• Temp Range ( DegreesF): n/a
• Temp Stability ( DegreesF): n/a
• Default Temp ( DegreesF): n/a
• Energy Factor: -
• Condensing Heat Exchanger: n/a
• Vent Maximun Run: n/a
• Energy Star Rated: No

Bosch 520 HN NG Tankless Water Heater, Indoor Use Warranty:
• 15 year limited warranty on heat exchanger
• 2 year warranty on all other parts

* On a combustible wall surface the unit should be mounted away from the wall to provide adequate clearance of the vent pipe.
* Not approved for use in mobile homes, boats, or RVs.

This Bosch Tankless Water Heater is turbine-operated and does not require the use of a pilot, battery, or electricity. Water flow ignites the burner, while the gas valve holds a consistent temperature at different flow rates.
520 HN NG

Installation Parts
1.5/5 Stars
6 reviews
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1/5 StarsPoor design, poor performance | We purchased this water heater in September of 2013, only to have it freeze and rupture, dumping water all over our basement floor. It is a very poorly designed and built water heater. I would not recommend it under any circumstances.

We had a tankless water heater in our house for over 20 years and it never froze, even when the pilot light went out. This Bosch freezes very easily because the heat exchanger is right at the top of the unit. Bosch offers absolutely nothing to guard against this problem, other than to recommend that customers consult with an HVAC firm. The only thing they did in our case was to point out that freezing was not covered by the warranty.
Recommended? No.
3/5 StarsSize and capability | Listen this is and always has been a 1 faucet sized unit at 117,000 BTU. Read up on it before you buy expecting 6 faucets to run simultaneously. It's abou 2.38GPM in cold climates and that's 1 2.25 GPM restricted showerhead or faucet only,
A true multi-user tankless costs about $2500-4000.00 installed depending on size and brand.
Did you really think an under $800 duplicates that???? Also you have to upsize the gas line to supply 117,000 BTU at point of heater installation. People use the same 1/2" their tank used always fail. As to installers, we've seen 100's of these as the Model 125B, 1600P/H working perfectly in a limited capacity it's based on a 30 year old mechanical design principal. Made in Portugal.
Recommended? Yes.
1/5 Starsdoesn't work | We had this unit in our house for nine months before finally giving up on it. From the beginning, it was awful. It would randomly cut off when we were taking a shower, usually after about 2 minutes, leaving the water ice cold. We had the Bosch-certified technician who installed it back many times, and he couldn't figure out what was wrong. Eventually he was told by Bosch that we needed new mixing valves on the showers. As unlikely as it was that valves would fail on TWO different showers at the same time, we went ahead and spent $700 on plumbing repairs at the insistence of the Bosch folks. The result was the same cold showers. We had the city check our water pressure and change our meter. Still no good. We had a tech from Bosch look at it. No one could fix it.

Finally, we told the installer to take it out and put in a tank. Out installer is refunding us the installation and price of the unit. We are trying to get some redress from Bosch for the unnecessary plumbing work and two service calls.

The thing is a lemon. We have a Bosch oven, too, and we had to replace the same part on it twice in 5 years. No more Bosch products for us, ever.
Recommended? Yes.
1/5 StarsLeaving Me In The Cold | My home is a small 2 story home with 1 1/2 baths. I get hot water in my shower for about 5 minutes then it goes cold, real cold. I have to run my dishwasher on ultimate wash and still dishes not cleaned. My teen aged sons are tired of taking cold showers. And lets never run the water in the sink when someone is shower. Very unhappy with system
Recommended? No.
1/5 StarsYes we've had many problems | I can only second what the first review said. We've had this unit for a number of years. It is now Sept 26 and getting a little chilly. It is 11am. I am sitting here in my nightie writing this review because I haven't had hot water yet to bathe! Too many days I need to heat water on the stove. Today I'll head to the Y because I need to wash my hair.

Yes it saves energy, because it doesn't even come on! Also Bosch would not speak with me about service. I have to call a contractor. There are only 3 within 20 miles.
Recommended? No.
2/5 StarsCannot handle more than one application | Does match up to the claims of multi applications usage. If you are taking a shower and someone washes their hands the system loses hot water pressure and turns cold, then back to hot. Cold temp rise is aweful. In the Northeast if the inlet temp is 45 degrees or less the system will collapse to try to get to required 115-120 degrees. Controls are very fickle. Bosch tech support had to talk me through the process to get it just right. Cannot have any long runs from the unit. Make sure you have a competent installer who knows how to properly size the unit to your house.
Recommended? No.
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Q:Is there a federal tax credit available against this model and/or a Vectren rebate?Anita | Thursday, November 7, 2013
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You would need to contact Bosch directly for that information and assistance.
Adam | Wednesday, November 13, 2013
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