Raychem HWAT-R2 Hot Water Temperature Maintenance Heating Cable

HWAT-R2 is the Raychem self-regulating heating cable for the 208-277 V version of the hot water temperature maintenance system. Installed under the pipe insulation of hot water supply lines, it replaces heat loss where it occurs and keeps water at 105 to 140 F (40 to 60 C) without a recirculation loop.

Keeping hot water at temperature without recirculation pipework

The datasheet describes the cable as adjusting its power output to compensate for variations in water and ambient temperature. A single-pipe HWAT system therefore removes the pumps, return piping and balancing valves of a conventional recirculation design, and the maker lists lower installed and operating cost as the result. Retrofits and multiple pressure zones are described as simple to design.

The cable has a modified polyolefin inner and outer jacket, a tinned-copper braid, a polymer-coated aluminium wrap and a self-regulating core on 16 AWG nickel-plated copper bus wires. HWAT-R2 has a red jacket and is the version for 208-277 V; the 120 V version is HWAT-P1 with a plum jacket.

Features stated in the datasheet

• Maintain temperature range 105 F (40 C) to 140 F (60 C) when designed with the HWAT System Product Selection and Design Guide.
• Designed and approved for use with the Raychem HWAT-ECO-GF electronic controller; the ACS-30 controller supports HWAT-R2 for large systems.
• Cut to length, spliced, tee-branched and terminated on site.
• Listed c-UL-us when used with the appropriate agency-approved Raychem components and accessories.

Technical specification

Specification of HWAT-R2

System parts that go with the cable

An HWAT system consists of the cable, a power connection kit, RayClic tees and splices at pipe branches, an end seal, and a controller. The installation manual names the RayClic, FTC-HST-PLUS or HWT-P connection kits and the HWAT-ECO-GF or ACS-30 controllers. The manual notes that a pipe temperature sensor must be used on the least-used pipe with HWAT-P1 cable.

Select the cable length per branch from the circuit-length table; the 208-277 V group allows longer runs than the 120 V cable, which the datasheet limits to 395 ft (120 m) on 30 A.

Installation and commissioning notes

Per manual H57548 the cable is attached to the pipe with glass tape under thermal insulation, and the insulation should follow immediately after tracing and testing so the cable is not damaged during construction. Fibreglass insulation must be a specific thickness per pipe size (Table 2 in the manual). Do not use metal straps or vinyl tape.

Read the scald warning: water above 130 F (55 C) is a significant risk of injury or death and requires scald protection. Extended 10 year warranty is available if the online warranty form is completed within 30 days of installation; it covers the cable and connection kits but not the controllers.

Where hot water maintenance cable is used

General engineering note: hotels, hospitals, accommodation camps and office towers in the Gulf have long hot water riser and branch pipework where recirculation systems waste energy. HWAT-R2 suits such building services, and not process piping, because the maintain range ends at 140 F (60 C).

In commercial buildings the manual flags trade coordination: heating cable must be installed, tested and insulated before walls are closed, because repairs afterwards may require opening them.

Information to send with an RFQ for the Raychem HWAT-R2 Hot Water Temperature Maintenance Heating Cable

Heat-tracing cable is quoted per metre or per reel, but the cable alone rarely completes a circuit. To get an accurate offer for the Raychem HWAT-R2 Hot Water Temperature Maintenance Heating Cable, list the pipe sizes and lengths to be traced, the maintain temperature, the lowest expected ambient temperature and the highest exposure temperature during steam-out or process upsets. State the supply voltage, the breaker rating you plan to use and whether the area is classified, with the gas group and temperature class required.

• Total cable length, with an allowance for valves, flanges, pumps and supports.
• Connection kits: power connection, splice, tee and end seal, plus attachment tape and labels.
• Thermal insulation type and thickness, because heat loss drives the watts per metre needed.
• Control method: ambient sensing, line sensing or an electronic controller with monitoring.

With this data the circuit can be checked against the maximum circuit lengths in the manufacturer’s design tables before the order is placed, which avoids nuisance breaker trips during cold start-up.

Related Raychem items

The matching controllers are HWAT-ECO-GF, which provides programmable temperature control, a heat-up cycle, a BMS interface and nine predefined programs, and ACS-30 for large multi-circuit systems. Process-temperature cables such as BTV are separate products.

Frequently asked questions

What temperature range does HWAT-R2 maintain?

105 F (40 C) to 140 F (60 C) when the system is designed per the HWAT guide.

What is the difference between HWAT-R2 and HWAT-P1?

HWAT-R2 is for 208-277 V and has a red jacket; HWAT-P1 is for 120 V, plum jacket, with 105-130 F maintain range.

How long can one circuit be?

At 208-277 V: 250 ft on 15 A, 330 ft on 20 A and 500 ft on 30 A breakers, per the datasheet.

Is scald protection needed?

Yes, the datasheet warns that water above 130 F (55 C) requires scald protection measures.

Does Seven Star LLC act as a Raychem distributor?

No. Seven Star LLC is not a Raychem distributor; it is an independent Muscat-based supplier that quotes Raychem products on request.

Documents and quotation

The official Raychem datasheet and user manual for HWAT-R2 are hosted on this page for download. Seven Star LLC is an independent supplier in Muscat; send your quantity and delivery location through the quotation form and we will quote this item. Please confirm the exact order code, supply voltage and output options against the documents before ordering. More related products: product category.