Shipping FREE on all orders over £75 - 
Separated from pack, in.therm is an intelligent remote heater that integrates electronics in its power box. It includes a built-in temperature probe and a new water flow detection feature that eliminates the need of a pressure switch.
In.therm controls multiple power levels on a single element extending its lifetime by heating at high power only when needed. With no moving parts and no adjustments, in.therm is hassle free and defines new levels of reliability.
KW: 2 & 3.8Kw ratings - pick yours in the options
Yours may state 4kw, the 3.8kw is the direct replacement, it is just badged up differently for the European market. The design of its unique seamless enclosure and its cover gasket eliminates all risks of water infiltration. Filled with epoxy, its electronic board compartment is protected against the stress of water flow vibrations.
This is for information only (use at your own risk) - We have seen the RHNF fault on this heater on an Arctic Spa and the following procedure has tested and sometimes rectified this fault
In.therm controls multiple power levels on a single element extending its lifetime by heating at high power only when needed. With no moving parts and no adjustments, in.therm is hassle free and defines new levels of reliability.
KW: 2 & 3.8Kw ratings - pick yours in the options
Yours may state 4kw, the 3.8kw is the direct replacement, it is just badged up differently for the European market. The design of its unique seamless enclosure and its cover gasket eliminates all risks of water infiltration. Filled with epoxy, its electronic board compartment is protected against the stress of water flow vibrations.
This is for information only (use at your own risk) - We have seen the RHNF fault on this heater on an Arctic Spa and the following procedure has tested and sometimes rectified this fault
On the PCB board - hold down the select ket for 5 seconds
You will see a LL followed by a number on the topside controller
Release the select key
Tap the change key until the number next to the LL on the topside is returned back to (i.e. scrolls back to this number)
Hit select key once
Hit the select key again
SC will appear for 1 min - this is the learning cycle
An X in a box will appear tap the key adjacent to it
The system should reset
If this fails then unfortunaltey the heater has failed and needs to be replaced