Haws TWBS.HF User Manual

)

INSTALLATION, OPERATION

&

MAINTENANCE INSTRUCTIONS

1455 Kleppe Lane Sparks, NV 89431-6467 [phone] Fax [phone]

E-mail: [e-mail] website: www.hawsco.com

No. 2080229 (5

Model TWBS.HF

Tempered Water Blending System

NOTE TO INSTALLER: Please leave this information with the Maintenance Department.

HAWS® warrants that this specific product is guaranteed against defective material or poor
workmanship for a period of three years from date of shipment. HAWS liability under this
warranty shall be discharged by furnishing without charge F.O.B. HAWS Factory any
goods, or part thereof, which shall appear to the Company upon inspection to be of
defective material or not of first class workmanship, provided that claim is made in writing to
Haws within a reasonable period after receipt of the product. Where claims for defects are
made, the defective part or parts shall be delivered to the Company, prepaid, for inspection.
HAWS will not be liable for the cost of repairs, alterations or replacements, or for any
expense connected therewith made by the owner or his agents, except upon written
authority from HAWS, Sparks, Nevada. HAWS will not be liable for any damages caused by
defective materials or poor workmanship, except for replacements, as provided above.
Buyer agrees that Haws has made no other warranties either expressed or implied in
addition to those above stated, except that of title with respect to any of the products or
equipment sold hereunder and that HAWS shall not be liable for general, special, or
consequential damages claimed to arise under the contract of sale.

The thermostatic mixing valve manufactured by HAWS is warranted to function if
installation and maintenance instructions provided are adhered to. The units also must be
used for the purpose, which they were intended. This product is intended to supplement
first-aid treatment. Due to widely varying conditions HAWS cannot guarantee that the use of
this emergency equipment will prevent serious injury or the aggravation of existing or prior
injuries.

NO OTHER WARRANTIES EXPRESSED OR IMPLIED ARE AUTHORIZED, PROVIDE D
OR GIVEN BY HAWS.

SHOULD YOU EXPERIENCE DIFFICULTY WITH THE INSTALLATION OF THIS
MODEL, OR REQUIRE REPLACEMENT PARTS, PLEASE CALL:

TECHNICAL SUPPORT:

LIMITED WARRANTY

1-800-766-5612

FOR CUSTOMER SERVICE: 1-888-640-4297

01/14 TWBS.HF Page 1 of 6

INSTALLATION, OPERATION & MAINTENANCE INSTRUCTIONS

Valve operating principle:

The Haws Corporation TWBS.HF Emergency Valve thermostatically mixes hot and cold water to provide
a safe fluid supply for emergency showers and eyewash equipment. The TWBS.HF valve contains a
secondary high temperature limit valve to provide additional protection to the user in the event of main
tempering valve malfunction. Additionally, to ensure a fail-safe water supply for emergency shower and
eyewash stations, a pressure sensing diverter valve is provided that sends a pressure signal to open the
cold water by-pass valve in the event of hot water pressure loss, main valve thermostat malfunction, or
clogged cold water check-stop.

Valve features:

‐ Paraffin filled thermostats with industry leading response time.
‐ Tempered water: Temperature is factory set to 85°F (29°C).
‐ Tempered water: High temperature limit is factory set to 85°F (29°C).
‐ The over temperature valve is calibrated to shut off the hot water inlet flow when the outlet

temperature exceeds 95°F (35°C).

‐ Cold water by-pass valve opens if hot water fails.
‐ Actively suspends hot water flow when cold water supply is lost to protect against scalding.

‐ Cold water by-pass valve is closed during normal operation, regardless of flow rate.

Valve sizing:

The flow capacity table shown below contains discharge flow rates @ 85°F (29 °C) outlet temperature with
the valve tested under the conditions described by ASSE 1071.

Flow Capacity

Model No. Min flow

TWBS.HF

* Denotes minimum flow rate without re-circulation.

1.0* GPM

5 PSI 10 PSI 20 PSI

32

GPM

Pressure drop across valve Cold water

40 PSI 45 PSI

90

GPM

95

GPM

By-pass @ 30 PSI

79

45

GPM

64

GPM

30 PSI

78

GPM

Valve specifications:

‐ Maximum operating pressure: 125 PSI
‐ Minimum / Maximum hot water temperature: 120°F / 180°F (49°C - 82°C).
‐ Tempered water temperature adjustment range: 60°F – 85°F (15°C - 29°C)
‐ Compliance/Listings: ASSE 1071, NSF 61, California Lead Plumbing Law and applicable

sections of CSA B125.3.

IMPORTANT

To ensure the proper operation of the TWBS.HF valve it is essential to:

‐ Properly size the valve for each application.
‐ Keep the outlet temperature set between 60°F and 85°F (15°C - 29°C).
‐ Haws recommends a weekly testing and recording of the outlet water temperature.

Failure to comply with installation and/or maintenance instructions could result in
valve failure.

01/14 Model TWBS.HF Page 2 of 6

INSTALLATION, OPERATION & MAINTENANCE INSTRUCTIONS

Valve operation:

Hot and cold water flows into the valve through two ports, marked “C” for cold and “H” for hot. The inlet
water passes through check valves and valve seats into a mixing chamber, where the main thermostat is
located. The temperature setting is controlled via an adjusting screw which is located at the front of the
valve. If the inlet temperature fluctuates or the pressure changes, the main thermostat moves an internal
plunger which corrects outlet temperature back to the initial setting. In the event of cold water failure, the
main thermostat completely closes the hot seat. Additionally, the cold water by-pass valve provides
adequate cold water flow if the hot inlet fails. For additional safety, a second high temperature limit
thermostat is located in the outlet stream. This thermostat shuts off at 95° F or higher temperatures,
closing the hot inlet.

Valve installation instructions:

Installation and field adjustment of this device are the responsibility of the
installer and shall be carried out in accordance with the following instructions:

1. This valve must be accessible for testing, adjustment and/or maintenance in its installed position.

2. Shutoff valves must be installed and closed for maintenance purposes, and provisions shall be made
to prevent unauthorized shutoff.

3. Flush the hot and cold supply lines prior to installation.

4. Connect the hot and cold supplies to the marked inlets.

5. Connect the outlet to the tempered water supply line.

6. Pressurize the emergency tempering valve and check all connections for leaks.

Installation test procedure:

1. Confirm the discharge temperature at the eyewash station or drench shower. Reset the outlet
temperature, if necessary, based on medical/safety authorities guidelines.(This establishes the pre­set level). Note: Turning the temperature adjusting screw counterclockwise will increase the
temperature.

2. Close the hot water supply: The cold water by-pass must open and provide significant flow.

3. Open the hot water supply: The outlet temperature should return to the pre-set level.

4. Close the cold water supply (Do not use the check valve.): The flow rate must comply with the
maximum cold shut off flow allowed by ASSE 1071 for this valve size.

5. Open the cold water supply: The outlet temperature should return to the pre-set level.

6. Close the cold water check valve: The cold water by-pass must open and provide sufficient flow.

7. Open the cold water check valve: The outlet temperature should return to the pre-set level.

Recommended valve testing procedure:

1. Open the eyewash and/or drench shower stations: Confirm and record the outlet temperature.

2. Close the hot water inlet: The cold water by-pass valve must open.

3. Open the hot water inlet: The outlet temperature should return to the pre-set level.

4. Close the cold water supply (Do not use the check valve.): The flow rate must comply with the
maximum cold shut off flow allowed by ASSE 1071 for this valve size.

5. Open the cold water supply: The outlet temperature should return to the pre-set level.

01/14 Model TWBS.HF Page 3 of 6