Isotherm Spa 25


The Isotemp SPA Stainless Steel Marine Water Heaters are available in 5 sizes ranging from 15 to 40 liters capacity (15, 20, 25, 30 & 40 liters).

All Isotemp tanks come standard with the innovative Isotemp Temperature Control Safety Mixing Valve which protects users from scalding hot water.  Water heated with engine heat exchangers can be heated to 190 degrees or more which can scald those unfamiliar with boat water heaters.  Water will also be heated to 160+ degrees with just the electric heating element alone. By adjusting the valve, the Isotemp thermostat-controlled mixing valve mixes the boat’s water with the hot water to deliver the temperature you want at the faucet. This mixing action also speeds recovery time and extends the volume of hot water you get from a smaller tank.

Type Volume (gal) Dimension (O x L) (inches) Weight (lbs)
Pressure release valve (bar)
Spa 15 4 12.4x 19 16 6
Spa 20 5.3 12.4 x 23 18 6
Spa 25 6.5 12.4 x 27 21 6
Spa 30 8 15.4 x 24 26 6
Spa 40 11 15.4 x 26 29 6


There are no reviews yet.

Be the first to review “Isotherm Spa 25”

Your email address will not be published. Required fields are marked *