HEAT TRANSFER FLUID
Engineering Specifications for Closed-Loop HVAC Systems
The Dow Chemical Company Thermal Fluids Business 100 Larkin Center Midland, Michigan 48674 Phone: 1-800-447-4369
GENERAL PRODUCT DESCRIPTION
* industrially inhibited ethylene glycol-based heat transfer fluid is manufactured by The Dow Chemical Company. Aqueous solutions of DOWTHERM SR-1
* fluid are designed to provide freeze/burst and corrosion protection, as well as efficient heat transfer, in water-based, closed-loop heating and air-conditioning systems.
DOWTHERM SR-1 * fluid has an operating temperature range of -60°F to 250°F; with fluid freeze protection to below -60°F, and system burst protection to below -100°F. The fluid contains corrosion inhibitors that are specially formulated for HVAC systems to keep pipes free of corrosion without fouling. DOWTHERM SR-1 fluid can be specified for use in new HVAC systems, or as a replacement fluid for use in existing systems. The fluid is dyed fluorescent pink to facilitate system leak detection.
DOWTHERM SR-1 * fluid is also suitable for ice storage systems — used either in the closed circulation loop from the chiller to the storage medium; or, in solution with water, in the medium itself.
Since DOWTHERM SR-1 *contains ethylene glycol which is harmful or fatal if swallowed, direct contact with food or drinking water should be avoided.
HVAC SYSTEM FLUID SPECIFICATION Closed-loop, water-based systems
1. FLUID MATERIAL
The ethylene glycol fluid to be used in such a system must meet the following requirements:
- The fluid must be an industrially inhibited ethylene glycol (phosphate-based). Specifically excluded are automotive antifreezes or any formulations containing silicates.
- The fluid must be dyed [fluorescent pink] to facilitate leak detection.
- The fluid must be easily analyzed for glycol concentration and inhibitor level, and easily reinhibited using replacement inhibitor readily available from the fluid manufacturer.
- For a system containing more than 250 gallons of fluid, annual analysis must be provided free of charge by the fluid manufacturer. Manufacturer must also provide testing guidelines for use by the operator of a smaller system.
- The fluid must pass ASTM D1384 (less than 0.5 mils penetration per year for all system metals).
2. FLUID INSTALLATION
Follow these installation procedures:
- Clean new or lightly corroded existing systems with a 1% to 2% solution of trisodium phosphate in water prior to the installation of industrially inhibited ethylene glycol fluid.
- Extensively corroded existing systems should be cleaned by an industrial cleaning company and all necessary replacements and repairs should be made.
- Use only good quality water in solution with the ethylene glycol fluid. Use water with low levels (less than 25 ppm) of chloride and sulfate, and less than 50 ppm of hard water ions (Ca++, Mg++). Distilled or deionized water is recommended. If good quality water is unavailable, purchase pre-diluted solutions of industrially inhibited ethylene glycol fluid from the fluid manufacturer or, if available, from the distributor.
3. SYSTEM DESIGN CONSIDERATIONS
Avoid use of automatic water make-up systems to prevent undetected dilution of the ethylene glycol and possible contamination of the water system.
- Install industrially inhibited propylene glycol fluid if local plumbing codes require, or if contact with potable water is possible. See HVAC system engineering specifications sheet for DOWFROST* heat transfer fluid (Form No. 180-01272-893 QRP).
*Trademark of The Dow Chemical Company
|4. 4.1 ||TECHNICAL DATA DOWTHERM* SR-1 Fluid, Product Description Composition, % by weight Glycols 95.4 Inhibitors and water 4.6 Color
Fluorescent Pink |
|Specific gravity at 60/60°F ||1.1250 -1.1350 |
|pH of solution containing 50% glycol ||9.0 -9.6 |
|Reserve alkalinity, minimum ||11.0 ml |
|4.2 ||Typical Properties of Aqueous Solutions† |
|Physical Property ||Temp. °F ||25% Glycol Solution ||30% Glycol Solution ||40% Glycol Solution ||50% Glycol Solution ||60% Glycol Solution |
|Thermal 40 Conductivity 180 Btu/(hr•ft2)(°F/ft) 250 ||0.262 0.303 0.306 ||0.251 0.288 0.291 ||0.231 0.262 0.265 ||0.212 0.238 0.241 ||0.196 0.217 0.220 |
|Specific Heat, Btu/(lb•°F) ||40 180 250 ||0.882 0.930 0.954 ||0.861 0.913 0.940 ||0.816 0.879 0.910 ||0.770 0.842 0.877 ||0.721 0.812 0.842 |
|Viscosity, Centipoise ||40 180 250 ||3.0 0.57 0.35 ||3.54 0.63 0.38 ||4.91 1.79 0.45 ||6.77 0.94 0.52 ||9.90 1.06 0.56 |
|Density, (1b/ft3) ||40 180 250 ||65.17 62.86 61.02 ||65.66 63.28 61.40 ||66.59 64.07 62.12 ||67.47 64.80 62.78 ||68.31 65.49 63.39 |
|†Typical properties, not to be construed as specifications. |
|4.3 ||Freezing and Boiling Points of Aqueous Solutions |
|Freezing ||% Glycol ||Boiling |
|Temperature, °F ||by Volume ||Temperature, °F |
|26 ||10 ||214 |
|16 ||20 ||216 |
|10 ||25 ||218 |
|4 ||30 ||220 |
|-12 ||40 ||222 |
|-34 ||50 ||225 |
|-60 ||60 ||232 |
|<-60 ||70 ||244 |
|-49 ||80 ||258 |
|-20 ||90 ||287 |
For further information, call...
In The United States And Canada: 1-800-447-4369 • Fax 1-989-832-1465 In Europe: +32 3 450 2240 • Fax +32 3 450 2815 In The Pacific: +886-2-25478732 • Fax +886-2-27174115 In Other Global Areas: 1-989-832-1560 • Fax 1-989-832-1465 www.dowtherm.com
NOTICE: No freedom from any patent owned by Seller or others is to be inferred. Because use conditions and applicable laws may differ from one location to another and may change with time, Customer is responsible for determining whether products and the information in this document are appropriate for Customer’s use and for ensuring that Customer’s workplace and disposal practices are in compliance with applicable laws and other governmental enactments. Seller assumes no obligation or liability for the information in this document.
NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY EXCLUDED.
Published April 2002.
*Trademark of The Dow Chemical Company Form No. 180-01274-402AMS