Manual - Basic water heater
Isotemp Basic water heater has been designed and produced to ensure that your water heater will
give long and trouble free operation for many years.
It is important, however, that your Isotemp water heater is correctly installed and maintained. Dur-
ing the winter period when the unit is not being used it is essential that it is drained to avoid risk of
damage due to freezing.
Every single Isotemp water heater is individually pressure tested prior to delivery and carries a 2
year factory warranty in respect of defects in material and/or manufacture and a limited 5 year
warranty on the inner tank.
Installation:
1. Placement:
The water heater may be placed in a suitable place with the engine water connectors on the water
heater below the level of the engine header tank. The connection hoses between the engine and the water heater
should be kept as short as possible
.
2. Mounting:
The water heater can be mounted horizontal, with the safety valve lowest, or vertical with all connec-
tions pointing downwards. The mounting brackets can be turned to fit the bottom or a bulkhead on board. Bear in
mind the weight of the unit when full of water.
3. Water connections:
3.1 Fittings:
Use only fittings and accessories made of non-corrosive material such as brass or stainless steel. Avoid
plastic fittings on the water heater depending on the heat. For the engine cooling water connections, use heat resis-
tant (100°C/210°F) reinforced rubber hoses, resistant to anti-freeze and pressure proved for 5 bar (70 psi). For the
fresh water, use heat resistant fresh water hoses (food industry quality). They shall be rated 8 bar (115 psi).
Seal the threaded connections with e.g. LocTite 242.
3.2 Engine connections (see schedule):
The water heater may be used with either fresh or sea water cooled
engines. The flow of cooling water from the engine through the water heater must be at least 2 litres/min. If the boat
has two engines, connect the water heater to one engine only.
Connection to the engine shall be done with min. 16 mm / 5/8” hoses and adaptors to avoid restrictions. See the in-
structions in the engine operators manual, regarding hose connection points.
3.3 Freshwater connections (see schedule):
The water heater is fed with fresh water from the electrical
fresh water pump. Max pressure 3 bar (42 psi). The hot water outlet, which also vents the water heater, should be
connected to a mixer tap at the sink and/or basin outlet. Cold water can be mixed with hot to avoid scalding. Set a
proper temperature on the thermostat mixing valve on the water heater, if fitted. The waste water hose must always
have a free outlet. There must be no valves or skin fittings, fitted to the waste water hose. A small quantity of water
may be expended via the safety valve during the heating up period.
