So it’s time… you need to flush your Rinnai tankless hot water heater, you know your supposed to do it every year but maybe you have even waited a little longer and now if I wrote this article for you it would be called: how to descale a rinnai tankless water heater. Well you came to the right place.
In this article, I will provide you with a step-by-step guide on how to flush your Rinnai tankless hot water heater, along with a every tool you need to get the job done. So, get ready to roll up your sleeves and give your tankless water heater the cleaning it deserves.
What you need in your toolbox.
- Crescent wrench
- Channel Lock Pliers
- Phillips Screwdriver
- Small submersible pump (Preferably 4GPM)
- Bucket (Large enough to submerge pump)
- X2 Garden Short Garden Hoses
- 4-Gallons White Vinegar (Cleaning grade works fine)
Step-by-step How To Flush Your Rinnai Tankless Hot Water Heater
Flushing a Rinnai tankless water heater is a straightforward job if you have the right tools and a bit of handy experience. However, I recommend setting aside 1-2 hours for the task, especially if you’re not experienced. Don’t worry if you’re not a pro; just follow these 13 steps, and you can save yourself a few hundred dollars in plumber fees and achieve the same professional result.
1. Turn off the power (both electricity and gas) to your tankless heater
This is an essential safety step to prevent any electric shock or gas leaks. You can turn off the power by switching off the circuit breaker and shutting off the gas supply valve.
2. Close the valves on both hot and cold water lines
This step is crucial to prevent the flushing solution from mixing with your household water supply. You can close the valves on both hot and cold water lines by turning them clockwise.
3. Use the service (isolation) valve and connect the circulation pump (such as a pond pump) to the cold water line (garden hose is OK)
The service valve is usually located near the unit and can be used to isolate the heater from the rest of the plumbing system. The circulation pump will help push the cleaning solution through the unit, and a garden hose can be used to connect the pump to the cold water line.
4. Pour the cleaning solution (vinegar or delimer) into the bucket
For this step, you can use approximately 4 gallons of white vinegar or a delimer specifically designed for tankless water heaters. It is recommended to get a non-toxic, non-corrosive, and biodegradable cleaning solution.
5. Now, connect the hose to the heater using another service valve and terminate it to the appropriate drain bucket
This step involves connecting the hose to the heater using a different service valve and running the other end of the hose into a bucket. The bucket will collect the flushing solution and any debris from the unit.
6. Drain and pump hoses should end in the same bucket and into the cleaning solution
This step ensures that both hoses (the one connected to the pump and the one connected to the unit) end up in the same bucket and submerged in the cleaning solution.
7. Open both service valves on the hot and cold water lines
This step involves opening both service valves on the hot and cold water lines to allow the cleaning solution to flow through the unit.
8. Run the circulation pump and let the flushing solution go through the unit for one hour approximately
After opening the service valves, you should turn on the circulation pump and let the cleaning solution run through the unit for about an hour. This will help remove any buildup or sediment in the unit.
9. Turn the pump OFF
Once the flushing solution has run through the unit for the recommended amount of time, you can turn off the circulation pump.
10. Rinse the cleaning solution from the water heater
This step involves flushing the cleaning solution out of the unit by opening the shutoff valve on the cold water line and letting it run through the unit and into the bucket for approximately 5 minutes. After that, open the shutoff valve on the unit and close the service valve between the heater and a bucket.
11. Disconnect all the hoses
This step involves disconnecting all the hoses from the unit and the pump.
12. Clean the in-line filter
After flushing the unit, it is recommended to clean the in-line filter to remove any remaining sediment or debris.
13. Resume the power and run the water heater
Once you have completed all the previous steps, you can resume power to the unit and run the water heater as usual.13
Frequently Asked Questions
Q: Does a Rinnai tankless water heater need to be flushed?
A: Yes, a Rinnai tankless water heater, like any other tankless water heater, needs to be flushed periodically to remove mineral deposits and scale buildup. Depending on the hardness of your water you should do this maintenance every 6-12 months.
Q: What can I use to descale my tankless water heater?
A: You can use a commercially available descaling agent specifically designed for tankless water heaters or white vinegar. For equipment, it can be bought in tankless hot water heater flushing kits.
Q: Is vinegar or descaler better for tankless water heaters?
A: Both vinegar and commercial descaling agents can effectively descale tankless water heaters. However, descaling agents may be more potent and efficient in removing stubborn scale buildup.
Q: Can I use vinegar to descale my tankless water heater?
A: Yes, you can use a mixture of equal parts white vinegar and water as a descaling solution for your tankless water heater. It is a natural and cost-effective option for descaling.
Q: How much does it cost to flush a Rinnai tankless water heater?
A: The cost of flushing a Rinnai tankless water heater yourself can vary depending on how much of the needed equipment you already own. A tankless water heater flushing kit plus needed solvents and tools will probably cost you about $150 but once you own all the necessary items just getting 4 gallons of white cleaning vinegar will cost only $10 for subsequent cleanings.
Q: How much does it cost to flush a Rinnai water heater?
A: The cost of flushing a Rinnai water heater, including both tankless and traditional tank-style units, can vary depending on similar factors mentioned above. It’s best to consult with local professionals to get accurate cost estimates.
Q: Can I flush my tankless water heater myself?
A: Yes, you can flush your tankless water heater yourself. However, it’s important to follow the manufacturer’s instructions and safety guidelines. If you’re not comfortable with basic plumbing tasks, it’s recommended to hire a professional to ensure proper and safe maintenance.
Q: What happens if you don’t flush your tankless water heater?
A: If you don’t flush your tankless water heater regularly, mineral deposits and scale wil accumulate inside the unit. This buildup can reduce its efficiency, lead to decreased water flow, cause heating issues, and eventually shorten the lifespan of the unit.
Q: How long is the life expectancy of a Rinnai tankless?
A: The life expectancy of a Rinnai tankless water heater can vary depending on factors such as usage, maintenance, water quality, and model. On average, a well-maintained Rinnai tankless water heater, that is flushed regularly, can last around 20 years or more.
Rinnai Error Codes That Flushing Your Water Can Fix
- Error Code 14
- Error Code 32
- Error Code 33
- Error Code 34
- Error Code LC or 00
Well, there you have it, folks! Your Rinnai tankless hot water heater is now flushed and descaled free from all that pesky buildup and sediment that can lead to decreased efficiency and higher energy bills. With just a few simple tools and some elbow grease, you can give your water heater the cleaning it deserves. So go ahead, pat yourself on the back for a job well done, and enjoy that nice, hot shower knowing that your tankless hot water heater is working at its best.