Garden / Outdoor
RUUD 199,900 Btu-h Tankless Water Heater Use and Care Manual
Quick guide for RUUD tankless water heaters. Includes installation, venting, gas supply, water connection, maintenance, and troubleshooting procedures.
Table of contents
Quick guide from the manual
This manual covers the installation, operation, and maintenance of RUUD non-condensing tankless water heaters (160,000 to 199,900 Btu/h models). Installation must be performed by a qualified professional. Always read the safety warnings regarding gas leaks and carbon monoxide before proceeding.
Safety Information
DANGER: Flammable vapors can cause explosions. Do not store gasoline or other flammable liquids near the heater. If you smell gas, do not operate any electrical switches or phones; call your gas supplier immediately from a neighbor's phone.
Installation
The water heater must be installed in accordance with local codes and the National Fuel Gas Code. Ensure proper clearance from combustible materials (1/2 inch for sides/front, 12 inches for top/bottom). For indoor models, use only manufacturer-approved Category III stainless steel venting. Outdoor models must be installed outdoors only.
Water Supply and Connections
Connect cold water to the inlet and hot water to the outlet. Use a pressure-relief valve at the hot water outlet. Ensure water quality meets the specified levels (pH 6.5-8.5, TDS up to 500 mg/L) to prevent damage. Insulate both hot and cold water lines to prevent freezing.
Gas Supply
Ensure the gas supply is properly sized for the heater's Btu capacity. Use a manual gas shut-off valve. Never attempt to convert the heater from one gas type to another. Leak test all connections using a soapy solution; never use an open flame.
Operation
The heater is activated by water flow. Use the remote control to set the water temperature (factory default 100°F-120°F). Temperatures above 125°F pose a severe scalding risk.
Maintenance
Perform annual inspections of the venting system, burner, and condensate trap. Clean the water filter monthly. If an error code appears, refer to the troubleshooting chart in the manual. For service, contact the Rheem National Service Department at 1-866-720-2076.
Practical help
Common problems
Not enough or no hot water
Check if the unit is ON, ensure gas and water valves are fully open, check for frozen pipes, or clean the water filter/aerator.
Water too hot
Decrease the temperature setting on the remote control or increase the water flow at the faucet.
Error code displayed
Refer to the Service Error Code Chart on page 77. Common codes include 11 (gas valve), 12 (gas supply), and 90/99 (venting/blockage).
Before use
- Is the main gas valve turned on?
- Is the electrical power connected?
- Is the water temperature set to a safe level?
- Is the unit properly vented to the outside?
- Is the water heater installed away from flammable materials?
Specs in practice
- Inlet Gas Pressure (Natural Gas)
- 4.0" w.c. to 10.5" w.c.
- Inlet Gas Pressure (LP Gas)
- 8.0" w.c. to 13.0" w.c.
- Water Pressure
- Minimum 14 psi required for operation; 40 psi recommended for maximum flow.
Images and diagrams
- Typical Direct-Vent installation shows the heater with a coaxial vent pipe, condensate trap, and gas/water shut-off valves.
- Outdoor installation diagram shows the unit without venting, requiring hard-wiring for power.
Model compatibility
- Only use manufacturer-approved Category III stainless steel vent material.
- Recirculation control is for residential use only and cannot be used with air handlers or multiple-unit manifold systems.
Manual page author
Emily Carter
User documentation editor
Prepares concise manual descriptions and highlights the most useful setup, operation, and maintenance information for readers.