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Keystone KS/KW

High Efficiency Condensing Boilers from 399 to 850 MBH

Keystone Condensing Boilers provide powerful solutions for large residential and light commercial applications with 5 models with inputs from 399 to 850 MBH. These products feature a stainless steel heat exchanger with a thermal efficiency between 95 and 97%. Their compact design minimizes floor space while the cabinet provides easy access to all components. The large user friendly control interface makes set-up easy. The advanced control modulates the boiler with a 5 to 1 turndown ratio. Up to 8 boilers can be joined in a cascade while the control features parallel modulation and boiler rotation to maximize efficiency and service life.

Keystone Condensing Boilers from 500 to 850 MBH are CSD-1 compliant as a standard feature. This saves both cost and installation time

OVERVIEW

  • Energy efficient with 95% to 97% Thermal Efficiency
  • Stainless Steel Heat Exchanger
  • CSD-1 Standard on 500 to 850 MBH Boilers
  • Integrated Cascade
  • Multiple pump control and thermostat inputs
  • 5 to 1 Turndown
  • 75 psi Pressure Relief Valve on Keystone Boilers

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GREAT VALUE AND SERVICE

"Was able to get a pretty uncommon part at a great price. Shipping was fast. Great experience overall."

– MichaelStrohman

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BEST PRICE, FAST SHIPPING

"No problems, found the part easily on the website and placed the order. Shipped out the next day."

– ZanyMockingbird

Verified by ResellerRatings

THIS ORGANIZATION IS FANTASTIC

"I highly recommend Parts4heating and will do all my business with them in the future."

– M MST

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GREAT VALUE AND SERVICE

"Was able to get a pretty uncommon part at a great price. Shipping was fast. Great experience overall."

– MichaelStrohman

Verified by ResellerRatings

EXCEPTIONAL

"These guys will be my first call for all of my parts needs going forward."

– Douglas Carocari

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EXCEPTIONAL

"These guys will be my first call for all of my parts needs going forward."

– Douglas Carocari

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EXCELLENT SERVICE

"The product was a good quality and the delivery time was good!"

– AverageFirefly

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COMPETENT STAFF CONCERNED ABOUT PEOPLE

"They know their products and they are not out to just make a sale."

– MikeRenna

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EXCEPTIONAL

"These guys will be my first call for all of my parts needs going forward."

– Douglas Carocari

Verified by Google Reviews

EXCELLENT SERVICE

"The product was a good quality and the delivery time was good!"

– AverageFirefly

Verified by ResellerRatings

COMPETENT STAFF CONCERNED ABOUT PEOPLE

"They know their products and they are not out to just make a sale."

– MikeRenna

Verified by ResellerRatings