Brian and Julie had a problem with their hot water cylinder at their Porirua home over the Christmas break. They contacted Paramount Plumbing and Gas and we attended quickly. The cylinder was underneath the house, leaking all over the place, and the platform it was sitting on had rotted out completely.
This is a job we see regularly across Wellington. Under-house cylinders are common in older Wellington homes, and when they fail, they tend to create secondary damage. A slow leak left long enough will rot the timber beneath it, and a rotted platform means the cylinder cannot simply be swapped out in place. The scope expands quickly.
Here is what we found, what we recommended, and why.
The Problem: A Leaking Cylinder and a Rotted Platform
Hot water cylinders rarely announce their failure dramatically. More often, a slow leak develops over weeks or months in an out-of-the-way location like a subfloor cavity, and by the time a homeowner notices, the surrounding structure has already taken damage.
Brian and Julie’s cylinder was located underneath the house, which is typical of many Wellington properties built in earlier decades. These under-floor installations keep the unit out of living areas, but they are harder to inspect and easy to overlook until something goes wrong.
When we arrived, the cylinder was leaking significantly and the timber platform beneath it had rotted through. Two separate problems needed addressing: the cylinder itself, and the structure it would need to sit on after replacement.
When a Leak Means Replacement
Not every leak requires a full replacement. A leak from a fitting, valve, or connection can sometimes be repaired without touching the cylinder itself. But a leak from the cylinder body is a different matter. Once the tank is compromised, repair is not a viable long-term solution.
In Brian and Julie’s case, the cylinder was leaking and the surrounding damage made the decision straightforward. A new cylinder was the right call.
The Solution: Rheem 16T18013 180L Low Pressure Cylinder
We quoted to replace the leaking unit with a Rheem 16T18013 180L Low Pressure hot water cylinder. Brian and Julie approved the work and we got it done.
Why We Recommended This Cylinder
The Rheem 16T18013 was the right fit for this job, and the reasons are practical rather than generic.
The Rheem 16T18013 is manufactured in New Zealand and offered the capacity, pressure rating and installation flexibility needed for this job.
It is designed to install easily in tight situations, which is a real consideration in under-house installs where access and clearance are limited. It offers three inlet options, bottom, left, and right-hand sides, giving the installer flexibility when working around existing pipework in a confined space.
The unit is rated for a maximum of 76kPa water pressure and is suited to indoor installation. It meets New Zealand Minimum Energy Performance Standards. At 180 litres, it is the right capacity for this household, comfortably serving two to three people in a moderate climate without over-specifying.
Each of these specifications was directly relevant to the conditions on site. This was not an off-the-shelf recommendation. It was the right cylinder for the space, the property, and the people living in it.
Warranty Cover on This Installation
| Cover | Duration |
| Parts and Labour | 1 Year |
| Cylinder and Tank Labour | 1 Year |
| Cylinder and Tank Replacement | 5 Years |
| Paramount Workmanship | 2 Years |
The five-year cylinder replacement warranty and two-year Paramount workmanship guarantee give Brian and Julie solid cover on both the product and the installation.
Sorting the Platform as Well
The rotted platform needed to be replaced before the new cylinder could be safely installed. We built a new platform and also arranged an electrician to assist with the installation, so Brian and Julie did not have to coordinate additional trades themselves.
Under-house jobs often come with secondary issues like this. Sorting the coordination on the customer’s behalf is part of how we approach the work.
What Brian and Julie Had to Say
Brian and Julie were pleased with how the job was handled. As they put it:
“Lovely people, really helpful and friendly, responded really quickly and provided a high quality job. Thanks very much.”
A fast response over the Christmas break, a clear recommendation, and a tidy result including the platform replacement. That is what we aim for on every job.
What This Means for Wellington Homeowners
We regularly encounter hot water cylinders installed beneath older Wellington-region homes. Because these spaces are easy to overlook, a slow leak can sometimes continue unnoticed until it has also damaged the timber beneath the cylinder.
A slow leak in a subfloor space can go undetected for a long time. By the time it is found, the timber damage is already done, and what could have been a straightforward replacement becomes a more involved job.
Signs that a cylinder may be reaching the end of its life include rust-coloured water, inconsistent hot water, moisture or staining around the unit, and visible corrosion on fittings or the cylinder body.
If you have an older hot water cylinder and have noticed moisture, staining, corrosion, rusty-coloured water or changes in hot water performance, it is worth having it inspected before a small problem becomes an emergency.
Our Wellington emergency plumbing team handles cylinder replacements and urgent callouts across Wellington, Lower Hutt, Upper Hutt, and Porirua, including under-house installations and jobs where secondary work needs to be coordinated alongside the replacement.
See more of our recent plumbing work and projects.
Talk to Paramount About Your Hot Water Cylinder
Whether your cylinder is actively leaking or you want to understand the condition of an ageing unit, we can attend, assess, and give you a straight answer.
We service Wellington, Lower Hutt, Upper Hutt, Porirua, and surrounding areas.
Contact us to book an assessment or discuss a replacement. Call 0800 02 72 72.