A low point drain can help empty a water heater by allowing sediment and water to flow out, but it may not fully empty the tank without additional steps.
Low point drains help remove water from RV plumbing systems, but their effectiveness for draining water heaters depends on your setup. While they can assist in draining, they may not remove all water from the tank.
How Low Point Drains Work
Low point drains are valves installed at the lowest points in your RV’s plumbing system. They serve two primary purposes:
- Draining water from pipes during winterization
- Relieving system pressure when switching water sources
These drains typically come in pairs – one for hot water lines and one for cold water lines. When opened, they allow water to drain from the connected pipes by gravity.
Connection to Water Heaters
The hot water low point drain connects to the outlet side of your water heater. This means:
- It can drain water from the heater’s outlet pipe
- It may partially drain the tank itself if positioned correctly
- Complete drainage usually requires opening the tank’s drain plug
Effectiveness for Water Heater Drainage
Whether low point drains can fully empty your water heater depends on several factors:
| Factor | Impact on Drainage |
|---|---|
| Drain position | Must be below tank outlet to work |
| Tank design | Some models drain better than others |
| Water pressure | Opening faucets helps create vacuum |
According to RV owners on MyGrandRV forums, some report complete drainage while others find significant water remains in the tank.
Limitations of Low Point Drains
These drains have several limitations for water heater emptying:
- Sediment buildup remains in the tank
- Some models leave 1-2 gallons of water
- May not reach the tank’s lowest point
Proper Water Heater Drainage Procedure
For complete drainage and maintenance, follow these steps:
- Turn off water heater power (gas/electric)
- Allow water to cool below 100°F
- Open pressure relief valve
- Open hot water faucets inside RV
- Remove anode rod or drain plug
- Flush tank until water runs clear
For Suburban water heaters, consider installing an access door for easier maintenance.
When Low Point Drains Help
Low point drains can assist in these situations:
- Quick partial drainage between trips
- Relieving system pressure before maintenance
- Initial water removal before full drain
Winterization Considerations
During winterization, low point drains serve an important role:
- They remove most water from pipes
- Help prevent freeze damage to plumbing
- May reduce antifreeze needed
However, as noted on R-Pod forums, you should still use compressed air or antifreeze for complete protection.
Alternative Drainage Methods
For more effective water heater drainage, consider:
- Installing a check valve for easier draining
- Using a water heater flush kit
- Adding a secondary drain valve
Manufacturer Recommendations
Most water heater manufacturers recommend:
- Annual complete draining for maintenance
- Using the designated drain plug
- Flushing to remove sediment
While low point drains can help, they shouldn’t replace proper tank draining procedures.
