Thermann  315L Gas Boosted Solar Hot Water System
  • 10


    Cylinder Warranty
  • 12


    Heat Exchanger Warranty
  • 15


    Tubes & Manifold Warranty



Thermann Evacuated Tube Solar gas boosted hot water systems provide an efficient and reliable supply of hot water by harnessing the suns energy. Additionally, during those few times when it may need a little help, the gas booster provides the perfect back up, ensuring piece of mind while still keeping your running costs low.

  • Leading industry warranties
  • Innovative technology
  • Lightweight systems- Heavy lifting not required
  • Energy efficient
  • Cyclone rated framework
  • Cost effective to run

Prices are inclusive of GST

Must be installed by a licensed plumber.

The Tubes

Step 1

The sunlight strikes the dark absorber coating inside the evacuated tube.

Step 2

The heat pipe transfers the heat up to the copper header pipe location in the insulated manifold box.

Step 3

A circulator moves water from the storage tank to the copper pipe warming the water. The solar heated water is then pushed into the storage tank for use. Anti-frost is built in to the Thermann system to ensure solar hot water can be provided even in cold regions.

how it works 1

Passive Sun Tracking

The round tube design of the Thermann system passively tracks the sun throughout the day giving the highest possible performance from early morning through to late afternoon.

how it works 2

System Set Up

how it works 4
No. People 3-5 4-6 5-9
No. Tubes 22 30 44
Gas Booster Size 26L 26L 26L

Storage Tank

Measurements (mm)250L GAS315L GAS400L GAS
Tank diameter (A) 617 617 705
Tank height (B) 1445 1765 1704
HW outlet 1211 1531 1445
PTRV port 1211 1531 1445
Top sensor port 992 1258 1208
Solar return port 764 953 932
Bottom sensor 457 551 554
Solar Flow 197 197 219
Cold Water Inlet 197 197 219
Dry Weight (kg) 71 92 116

Specifications correct for units manufactured after 1st August 2016 (including some manufactured prior to this date). 

Continuous Flow Unit

Nominal hourly gas consumption (MJ/h) 200
Test point pressure NG (kPa) 0.8
Test point pressure LPG (kPa) 1.5
Capacity at 40°C rise (L/min) 16.25
Minimum working pressure (kPa) 110
Maximum working pressure (kPa) 1200
Gas injectors diameter NG (mm) 1.15/1.65
Gas injectors diameter LPG (mm) 0.7/1.0
Input voltage single phase 50Hz (v) 240
Maximum output current (A) 0.46
Inlet gas connection male thread R3/4” (20mm)
Cold water connection male thread R3/4” (20mm)
Hot water connection male thread R3/4” (20mm)
Relief valve pressure setting (kPa) 1400
Weight dry (kg) 16
Dimensions (DxWxH mm) 165x350x575

Roof Collector

Measurements (mm)Dry Weight
Collector Width (A) Length (B) WO/Tubes W/Tubes
22 Tubes 1636 2005 20kg 80.7kg
30 Tubes 2196 2005 24kg 105.7kg

Dry weights based on 2 track flush mount frame.

ResizedImage262484 electric evacuated tube tank tech drawingtech diagram gas boostertech diagram tubes

When choosing a hot water system, there are a number of factors you need to consider beyond the unit price. Installation costs can vary greatly for different types of hot water units. Ongoing running costs should also play a part in your purchase decision.

running cost chart

Guide only based on current average energy cost. This chart does not account for increased Electricity or Gas costs in coming years.

Where to Buy

Thermann hot water systems are available exclusively through Reece Plumbing. Find your nearest branch by entering your postcode below.

(You will be taken to the Reece website)


Here are the most common questions we get asked about hot water.

Get in Touch

Want to find out more about any of the hot water systems in the Thermann range? We’re happy to help.