/ Advanced Heating and Hot Water Systems / Guide Specification Sheet
P.O. Box 429 ∙ 120 Braley Road ∙ East Freetown, MA 02717
508-763-8071∙ Fax: 508-763-3769 / Commercial Tankless Water Heater
Models: CT-750 / CT-1000

The CT-750 / CT-1000 water heater manufactured by HTP, Inc. includes two (2) models with modulation inputs ranging from 30,000 to 750,000 BTU/HR (CT-750) or 30,000 to 1,000,000 BTU/HR (CT-1000). Model CT- having a modulation input range of Btu/Hr and shall operate on Natural or LP gas.

The water heater shall be National Board Listed and bear the ASME "HLW" Stamp with a maximum working pressure of 160 PSIG. All mechanical connections are located at the rear of the water heater. The water heater shall be used in an open loop system and require a properly sized thermal expansion tank to meet local codes. The water heater shall be ETL Listed and exceed the latest minimum efficiency requirements of ASHRAE 90.1b with a thermal efficiency up to 94%.

The water heater shall be constructed of individual independent heat exchanger modules (CT-750 – three (3) heat exchangers / CT-1000 – four (4) heat exchangers) manifolded to provide single point connections for the gas / water / vent piping systems. Each individual heat exchanger shall be constructed of laser welded 316L finned tube without any weld joints to secure the heat exchanger into the manifold or casing. The heat exchanger is sealed through multiple EPDM seals which allow the heat exchanger to flex, minimizing stress on the heat exchanger and promoting long service life. Each heat exchanger shall be passivated after welding to resist corrosion. The heat exchanger shall be a helical design and vertically positioned to provide optimal condensation drainage and produce self-cleaning action inside the water heater. The water heater is built and tested in accordance with the harmonized ANSI Z21.10.3 standard for the US and Canada. The heat exchanger assemblies shall carry a six (6) year commercial use limited warranty.

The water heater shall be equipped with a premix modulating combustion system, allowing the unit to provide high turndown ratios of up to 25 to 1 for the CT-750 / 33 to 1 for the CT-1000. The combustion system burners are constructed of high temperature metal woven fiber, providing operating reliability through the modulation range of the water heater. The negative pressure gas valve operates at very wide ranges of inlet pressure from 3 ½ to 14” of water column.

The water heater is floor mounted. The water heater cabinet shall be constructed with a heavy gauge steel enclosure assembly, with built-in manifold assemblies for the gas / water / vent / electrical / condensate systems.

Each individual module shall have an integrated digital control which monitors the incoming inlet and outlet temperatures and flow rates to assure a highly accurate temperature control. Modulating combustion will adjust the fan speed to provide only the input necessary to meet hot water demand. The flow control valve assures that the water heater and its individual modules deliver the desired outlet temperature.

The control will provide the capability to cascade up to 4 water heaters for greater system turndown and back up reliability. Cascade loops will also provide unit rotation plus isolation within the cascading circuit for greater system efficiency when recirculation lines are used. The control will also monitor safety through a series of sensors, including a flue temperature sensor, water temperature limit control, and a flue pressure switch to ensure there is no blockage in the vent system. Freeze protection is also provided. Each combustion systems have a built-in outlet check to eliminate back pressure issues and allow common venting.

The water heater shall have a sealed combustion system, and use minimum 6” diameter ULC-S636 PVC, CPVC, Polypropylene, or Stainless Steel designed for Category IV venting to provide intake air for combustion and vent exhaust flue gasses to the outdoors. The vent connections shall be located on the top of the water heater. CAUTION: Foam core pipe is NOT an approved material for either intake or exhaust piping.

The water heater can be vented in a Two Pipe Direct Vent System, where the water heater intake and exhaust are both piped directly to the outdoors, or utilize a Single Pipe Power Vent System, where Indoor Air taken from a Confined or Unconfined Space is used for combustion and the exhaust is vented to the outdoors. Water heaters shall vent a distance of 120 combined equivalent feet (CT-750) / 65 combined equivalent feet (CT-1000) in a two pipe direct vent system and 220 combined equivalent feet (CT-750) / 130 combined equivalent feet (CT-1000) in a single pipe power vent system. Multiple cascaded water heaters may also be Common Vented. Refer to water heater installation manual venting section for additional venting requirements.

The water heater shall be in compliance with the NOx emissions limit set forth in SCAQMD Rule 1146.2. The manufacturer shall verify proper operation of the burner, the combustion and control systems, as well as all related safety functions, to ensure the water heater will operate based on its designed parameters before shipping. Complete operating and installation instructions shall be furnished with every heater as packaged by the manufacturer for shipping. The water heater shall operate at altitudes up to 4,500 feet above sea level without additional parts or adjustments.

Maximum unit dimensions shall be: Depth 54 ¾ inches, Width 30 inches and Height 64 inches. Maximum unit shipping weight shall be 525 pounds (CT-750) / 590 pounds (CT-1000).

NOTE: HTP reserves the right to make product changes or updates without notice and will not be held liable for typographical errors in literature.

LP-530 Rev 8.7.14