Hot water (HUW)
Configure domestic hot water on the TIS Tronic 260U — Summer and Winter modes, HUW priority, hysteresis, working hours and the boiler temperature increase function.
The hot water module is off until you switch it into Summer or Winter mode — the greyed-out HUW main screen is the sign it has never been configured. Once active, it drives the pump on Q4 from the tank sensor on T2.
Switching the hot water pump into Winter or Summer mode moves the home screen from inactive (grey background) into active mode. From that moment the HUW pump operates in the selected mode, and the set HUW temperature can be changed directly on the HUW main screen with UP and DOWN.
Modes
| # | Mode | Effect |
|---|---|---|
| 1 | Winter with priority | Disable the heating pump to fill the DHW faster |
| 2 | Winter without priority | Simultaneous operation of heating and DHW pump |
| 3 | Summer | Enable DHW in summer without the central heating system |
| 4 | Off | Disable DHW |
The sensor gates the mode
If the DHW sensor on T2 is disconnected, the mode cannot be changed.
The main purpose of the boiler is to prepare hot water in the tank.
All other pumps are switched off — except when the boiler reaches a temperature higher than the maximum boiler temperature parameter, after which all pumps switch on to protect the boiler from overheating.
Central heating pumps and the hot water pump operate simultaneously.
Switching to Winter activates the HUW priority, working hours and temperature increase settings below.
The HUW pump is turned off. The grey screen is responsible for displaying information about the HUW temperature, but nothing is controlled.
Parameters
How far the tank temperature must fall below its setpoint before the HUW pump restarts.
Example: with the set temperature at 40 °C and hysteresis 2 °C, the pump starts working after the temperature drops to 38 °C.
| Range | 1 … 15 °C |
| Factory default | 5 °C |
Setting this to "on" turns off the central heating pump, and the water in the hot water tank is heated first. The hot water temperature gets a higher priority than the temperature set on the boiler.
The maximum time the HUW pump will try to reach the set tank temperature.
When the tank temperature drops by 5 °C from the user-set value, the pump switches on again until the set temperature is reached. This parameter caps how long that attempt may run, so the central heating system does not cool down intensively while the tank is being heated.
Available only when the HUW pump is running in Winter mode with priority enabled.
| Range | 10 … 240 minutes |
| Factory default | 30 min |
How many degrees the boiler temperature may rise above its own setpoint to speed up hot water preparation.
Example: boiler set to 50 °C, HUW set to 60 °C, HUW temperature increase 5 °C → the boiler temperature will be raised to 65 °C during the hot water preparation period.
| Range | 5 … 15 °C |
| Factory default | 5 °C |
Alarms related to hot water
| Alarm | Meaning |
|---|---|
| HUW overheating | The temperature in the tank has exceeded 85 °C |
| Temperature measurement error, HUW | The T2 sensor is missing or damaged |
Hardware
| Item | Detail |
|---|---|
| Pump output | Q4, rated 1 A |
| Tank sensor | T2, 3 m lead, KTY-81-210 |
| Recommended tanks | APOLLO DHW80 (combined buffer + indirect), DHW250 in the full scheme |
For a 120 V circulator on Q4, wire it through the supplied 220 VAC relay block — see Pump wiring.
Cycling the central heating pump once the room is up to temperature.
Frequently asked questions
Boiler settings
Every parameter in the TIS Tronic 260U boiler settings menu — hysteresis, maximum and shutdown temperatures, pump start, fan type, firing-up time and cooling temperature.
Room thermostat control
How the TIS Tronic 260U uses a room thermostat on I2 — pump cycling once the room is satisfied, operating and pause times, and the overheat override.