Water Tight Blog

What can cause Fluctuating Hot and Cold Water Temperatures in a Unit Complex?

Strata Hot Water Plumbers in Canberra

We often get asked what can cause Fluctuating Hot and Cold Water Temperatures in individual apartments and who is responsible for paying the bill. Note, for this blog post we are referring to sites that have a common hot water system. 


I always try and avoid discussions on who pays the bill as Strata Legislation is complex and to make it worse, often things are interpreted differently between Strata Firms and even between complexes within Strata Firms. 

The following information is accurate to the best of our knowledge. 

Problems and Responsability 

As general guidance and to the best of my knowledge, items that could cause a unit to have fluctuating water temperatures include and who is responsible,

Unit Owner Responsability

  1. Failing or poorly installed tempering valve
  2. Failing or missing cold water pressure reduction valve 
  3. Failing or missing hot water pressure reduction valve 
  4. Failing hot water non-return valve
  5. Failing cold water non-return valve
  6. A cross connection (hot and cold) within the unit itself. Eg a capped-off shower with the taps open

Owners Corporation Responsability

  1. Poorly Maintained Hot Water System
  2. Hot Water Infrastructure is inappropriately sized for the building’s demand requirements
  3. Ring Main Pump or Sensor Failure
  4. Balancing Valve Failure
  5. A Cross Connection elsewhere on the property

Neighbouring Unit Owner’s Responsibility

  1. A Cross Connection within a neighbouring unit can affect the other units that share the common water line

Who Should Investigate And Repair The Issue?

Unless multiple units are experiencing the same issue, who should have their assets tested first is a bit of a Chicken/Egg scenario. 

Ultimately, the time taken to investigate Common hot water asset faults is generally considerably longer/more expensive than testing the Unit Owner’s assets. For this reason, we would recommend the person experiencing the issue engage a plumber to have the recommended 5 yearly maintenance carried out and their internal valves tested and adjusted if required. 

Word of Warning – We regularly attend jobs where unit owners have had General Plumbers, rather than Strata Specialist Plumbers, attend to investigate hot water supply issues where faults and comprehension of the issue at and is missed. This occurs so often that when we are engaged by a Strata Manager to investigate these issues we always start with testing the affected unit first, regardless of the report they have submitted, and the problem is often found to be an internal issue that has been miss-diagnosed by the attending plumber. 

We understand the desire to use your plumber mate, neighbour’s kid, the Property Manager’s plumber or the cheapest guy in the phone book, but this is one area where getting an experienced Strata Specialist Plumber in Canberra can save you hundreds or even thousands of dollars. A quality specialist company, Like Water TIght Canberra 🙂 will have tradespeople that have been trained on the issue, they will have systems in place and they will have investigated these issues many times before. 

If you would like us to attend to your home to conduct hot or cold water supply tests, please fill in our job booking form. 

Alternatively, it may be preferable for you to contact your Strata Manager, ask them to issue a PO to Water Tight Canberra to investigate the issue, and confirm with them that if we find the issue is related to your own assets that are faulty, you will reimburse them for the associated costs or pay the invoice to us directly. 

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