6
of the fuse or tripping of the circuit breaker indicates a fault, which must be investigated by an authorised
tradesperson.
Lack of hot water reducing to warm water
• Are you using more hot water than you think?
• It is sometimes difficult to judge how much hot water your shower or other outlets use by observation
alone. Place a measured bucket under your shower for ten seconds and multiply by six to determine the
amount of water produced over a minute. Typical showers range from 8-12 L/min and basins 6-8 L/min, if
your result is significantly more you may want to consider installing a more efficient outlet or after market
flow restrictors.
• Cold water relief valve discharging continuously?
• As a hot water cylinder reheats after use it is normal for the cold water relief valve to discharge a small
quantity of water through the drain line. If water is discharging continuously there may be a fault with one
of the valves which needs to be rectified by a qualified tradesperson.
Water is too hot
• If possible check the temperature of the water coming out of a hot outlet with a thermometer.
• If it is higher than 55 °C contact a qualified tradesperson for advice.
High electricity bills
• In addition to any of the above reasons;
• Check your electricity tariff hasn’t changed.
• Do you have an unknown leak in the system?
• Ensure every tap and outlet is turned off and check your water meter to ensure it is not still flowing.
8. Water Quality
Some NZ water supplies are particularly aggressive and can cause premature damage and reduced life expectancy
for hot water cylinders or any other appliance connected to them. Protank hot water cylinders are manufactured by
RM Cylinders in the UK from the highest quality Duplex 2304 stainless steel which is the most corrosion resistant
cylinder available in NZ.
Pitting Corrosion
Although Duplex 2304 has a very high resistance to pitting corrosion, it is not completely immune and corrosion can
still occur if the water supply has a high percentage of dissolved solids present. It is advised in areas with a high
concentration of dissolved solids in the water supply that consultation with water quality and filtration experts be
undertaken.
Hard Water
Hard water (containing calcium carbonate) can cause scaling on hot surfaces and we recommend a water storage
temperature of no more than 65 °C to minimise scale build-up. Material quality cannot influence damage due to
scaling therefore we offer no guarantee against it occurring. Scale reducing or water softening devices should be
considered in hard water areas.
Water Quality and Impurity Limits
Protank warranty conditions require the following minimum water quality and impurity limits are not exceeded;
TDS (Total Dissolved Solids):
Up to 600 mg/L or ppm
Total Hardness CaCO
3
:
Up to 200 mg/L or ppm
Dissolved (free) CO
3
:
Up to 25 mg/L or ppm
pH: 6.5-8.5
Langelier Index:
Between -1.0-0.8
