Tankline
For Rinnai Control-R tankless water heaters
Hot water in one tap, from your iPhone on your home Wi-Fi: no account, no cloud, no subscription.
For tankless water heaters with a Rinnai Control-R Wi-Fi module · iPhone · In development — not yet on the App Store
What it does
- Hot water now: starts the recirculation pump for 5, 15, 30 or 60 minutes, shows the minutes left and stops it on request
- Shows the temperature setting, the water out and the water in, and whether the heater is heating, live
- Changes the temperature with + and −, in the steps your heater accepts
- Finds the Control-R module on your home Wi-Fi by itself
- Says plainly when the heater did not take a command: every command is checked against the heater's own status
- Temperatures in °F; in English and German
How it works
Tankline talks to your heater's Wi-Fi module directly on your home network. It works without the internet and without any cloud service, so it does not depend on Rinnai's app or servers. There is no account, no tracking and no advertising. Tankline sends the module only values the heater accepts, and the heater's own safety limits always apply. Tankline works at home only: it has no remote access over the internet.
Works with
Rinnai tankless water heaters with a Control-R Wi-Fi module that has already joined your home Wi-Fi. Your iPhone must be on the same Wi-Fi as the module. Not every module generation offers local access: the free live view shows whether yours works before you buy Pro. "Hot water now" needs a water heater with a recirculation pump. No water heater nearby? The app has a demo where every control works.
Price
Free to download: the live status of one water heater. Tankline Pro is a one-time purchase (no subscription) that adds Hot water now, changing the temperature, and more than one water heater.
Questions owners ask
My Rinnai Control-R app is not working or not connecting. Can Tankline help?
Tankline does not use Rinnai's app or cloud: it talks to the module on your Wi-Fi. If the module is on your home Wi-Fi and offers local access, Tankline can show the heater and start hot water even when the cloud app does not. It cannot repair a module that has not joined your Wi-Fi, and it cannot reach one that offers no local access.
Do I need Home Assistant?
No. Tankline is a standalone iPhone app. Like a Home Assistant setup it uses your module's local connection, but you install nothing else and set nothing up on a server.
Which Wi-Fi module?
The Rinnai Control-R Wi-Fi module. First setup of the module on your Wi-Fi is done the way Rinnai describes; after that Tankline can look for it on your network. Some newer modules may not offer local access and cannot be used.
Can it start the recirculation pump, like a timer or a button?
It works like a button: "Hot water now" runs the recirculation pump for the minutes you choose and stops when they are over, or when you tap Stop. Tankline has no schedules. The heater needs a recirculation pump; on a heater without one the app says so instead of showing the button.
Is it safe to change the temperature from an app?
Tankline sends only values your heater accepts, checks the heater's status after every command and tells you if the heater did not take it. The heater's own limits apply. Above 120 °F the app reminds you that water can scald.
Does it work away from home?
No, only on your home Wi-Fi.