MJM Yachts 34z Express - Manual (Page 27)

CHAPTER 7 FRESHWATER SYSTEM
- 27 - 34z
7.1 GENERAL
Your boat incorporates a pressurized freshwater system. [See Figure 14.5] A single 60-gallon
tank supplies a pump which maintains a constant pressure in the system. An accumulator stores
this pressure so that the pump does not need to cycle every time a faucet is opened.
7.2 FILLING
A deck fill is provided on the port side deck and is labeled WATER. As the tank is filled, air
escapes thru the vent.
7.3 USING
& MAINTAINING
The freshwater pump is turned on at the DC breaker panel. If the pump is heard running
continually, check that no faucet has been left open. If this is not the case, turn off the pump and
check that the tank has not been emptied. The freshwater system is not a perfectly sealed circuit
and it is not uncommon to hear the pump cycle, but if this short cycling occurs more than once
per hour, the system and/or pump should be checked for leaks. Some users will want to turn the
pump off at night to avoid hearing it cycle.
The pump is protected from sediment by an in-line strainer mounted adjacent to the pump. The
strainer should be checked periodically and cleaned if necessary.
7.4 HOT
WATER
Water in the ten-gallon hot water tank is heated in one of 2 ways (1) whenever the engine is
operating or when the engine is not running, by turning on the “Water Heater” breaker on the
optional AC Electrical Panel. It is part of the freshwater system and does not need to be filled
separately. There is virtually no need for maintenance, but the connections at the tank should be
visually inspected occasionally.
The coolant lines from the engine to the tank have shut-off valves, located in the forward port side
of the engine compartment. These need to open in order for the engine to heat the water in the
tank. For service, or in case or a ruptured line, these valves can be closed to stop this water loop.
7.5
WATER PURIFIER (Optional)
[See also Seagull owner’s manual] The galley is fitted with a water purifier. This purifier has a
cartridge (in stainless pressure vessel under sink) that should be replaced annually or when
reduced water flow indicates that it has become plugged with sediment. It is best to clear the
pressure water system of any winter anti-freeze before running water through the cartridge.
The filter is rated for 1000 gallons, which is approximately 15 water tanks’ worth.