Your cylinder may just need a repair, not a replacement.
Does your hot water cylinder suffer from one of the following conditions?
- No Hot Water
- Very Low Temperature
- Knocking (Banging) Noises
- Hot Water Smells
- Low Pressure
- Leaking Hot Water Cylinder
- Damaged Hot Water Cylinder
- Discharge Valves Running Constantly
First things first, DON’T PANIC!
Your hot water cylinder may be repairable.
Hot Water Cylinders NZ provide unique repair options for most hot water cylinder related faults. Before jumping into an expensive replacement, get the professionals in to investigate and repair the problem at a fraction of the cost.
Hot Water Cylinder Faults and Remedies
NO HOT WATER (Temperature)
Possible Faults: Faulty thermostat, faulty element, blown fuse, power provider ripple control.
Possible Remedies: Replace thermostat, replace element, replace fuse, unsubscribe, ripple control.
NO HOT WATER (Physically)
Possible Faults: Blocked tempering valve, blocked strainer, incoming water problem, various possible blockages, damaged valve.
Possible Remedies: Process of elimination, identify fault and repair.
VERY LOW TEMPERATURE (or High/Low Fluctuation)
Possible Faults: if applicable, incorrect controller or thermostat settings, damaged element, damaged or wrongly set tempering valve, damaged diffuser, possible blockages, tapware problem.
Possible Remedies: Change thermostat and/or controller, tempering valve settings. Process of elimination, identify fault and repair.
KNOCKING OR BANGING NOISE (Water Hammer)
Possible Faults: This fault can appear when upgrading from low to mains pressure. Existing pipework not fixed properly, plumbing priority wrong, too much pressure, damaged valves, damaged or unsuitable tapware.
Possible Remedies: Find and fix loose pipework, improve existing priority, install water hammer arrestor. (For more information please view our “what is water hammer” blog.)
HOT WATER SMELLS BAD
Possible Faults: (External Smell) Typically an issue that relates to older cylinders or cylinders that have been slowly leaking internally (element thread or minor crack) for longer periods of time. When the insulation between the casing and tank is wet for a long period of time, it will rot and start to smell. (Internal Smell) A bad smell coming from the tap when hot water is running may be caused by the following: Bacterial growth due to minimum HWC temperatures not being met, accumulated sludge/rust caused by insufficient protection against electrolysis(?) due to the breakdown of a sacrificial anode. Incoming water affected by filthy water tanks or non-treated roof water. Note that smell is heightened by the higher water temperature.
Possible Remedies: Replace hot water cylinder, process of elimination, identify fault and repair.
Possible Faults: This fault will depend on whether it’s an existing low pressure problem or whether it’s a new low pressure problem. (Existing) Existing low pressure system and no fault, damaged pressure reducing valve, incoming pressure changes, tapware, related valve issue, excessive sludge/debris blocking outlet. (New) Tapware, blockages, valves, incoming pressure.
Possible Remedies: (Existing) Replace/repair valves/tapware, remove blockages, insert booster pump, upgrade to mains pressure. (New) Replace/repair valves/tapware, remove blockages. Process of elimination, identify fault and repair.
LEAKING HOT WATER CYLINDER
Possible Faults: Split welded seams or welded connections caused by various reasons including thermal expansion and contraction, typically seen with older leaking hot water cylinders, loose fitting, damaged fitting/valve, overheating causing condensation, worn element washer.
Possible Remedies: Repair leak where possible, hot water cylinder replacement.
DISCHARGE VALVES RUNNING CONSTANTLY
Possible Faults: In most cases there is no fault at all. The cold water expansion valve (considered the energy valve) may discharge up to 20L/day in very hot weather and no hot water usage. The idea is to discharge cold water instead of hot water to save on power which is much more expensive than water. Faulty valve, faulty TPR, debris blocking valve spring.
Possible Remedies: Follow manufacturing instructions to manually discharge water from valve to remove debris, regularly maintain valves, repair or replace faulty valves.
In some cases a repair is not possible or recommended, especially if it’s not economical or safe to do a repair. Depending on the fault, our team is trained to make the recommendation that will assist you with your budget and requirements.
WARNING!! When older cylinders are repaired or an element is replaced, they must be drained to enable the process of repair. This draining will cool down the cylinder tank and reduce its pressure. Consequently higher expansion and contraction will take place when the cylinder is re-pressurised (refilled with water). This process may result in an already poorly welded tank seam cracking which would result in a leak. The danger is that a seam cannot be repaired and a full cylinder replacement would be required, rendering the original repair redundant.
This information may be updated regularly to accommodate new information.