24 Jun 2025

76A Redhill Road HDB

Water Heater Corrosion Replacement: Joven JH15 to Joven JSH25 at 76A Redhill Road HDB on 23 Mar 2024

A homeowner at 76A Redhill Road HDB reached out to Homeone after observing brown water marks and signs of leakage near their ceiling-mounted water heater. Our site inspection revealed a serious case of "Water Heater Corrosion"—with visible rust along the bottom of the tank and fittings of the ageing Joven JH15 unit.

The tank’s exterior had oxidised, and the enamel coating was flaking away. In addition, the installation was non-compliant with multiple Singapore standards—there was no double check valve to prevent backflow contamination, no drainpipe connected to the temperature and pressure relief valve, and no electrical bonding, posing a safety risk for electrocution.

Project location
76A Redhill Road HDB
Property type
HDB

Before

Replacement of a Joven JH15 water heater to resolve heater problems end of service life.

After

The Joven JSH25 has been newly installed to the existing water heater system, with all connecting pipework made of stainless steel. The installation includes a new stop valve, double check valve, drain pipe, electric bonding, and 2.5mm² wire, and a submission has been filed to PUB to ensure safety and compliance with PUB regulations. Additionally, Homeone offers a 1-year warranty on this installation, complementing the manufacturer's warranty, ensuring peace of mind and reliable service.

Table of Contents

Water Heater Corrosion Replacement: Joven JH15 to Joven JSH25 at 76A Redhill Road HDB

Old Water Heater:

Joven JH15

Old Water Heater:

Joven JSH25

Site Findings

Severe water heater corrosion on the bottom and sides of the JH15 unit
Leaking rust stains are visible on nearby pipe joints and tiles
No drainpipe installed—relief water discharged freely and unsafely
No double check valve to protect against water backflow (SS636 violation)
No electrical bonding, violating CP5 Clause 413-02
Unit at the end of the lifespan, increasing risk of tank rupture and electrical hazard

Proposed Solution

To eliminate the risks posed by the water heater corrosion, Homeone recommended upgrading to a new Joven JSH25 unit (25L), offering increased capacity and internal corrosion resistance. The new installation was completed in full compliance with PUB and EMA regulations.

Scope of rectification included:

Removal of the corroded JH15 unit
Installation of double check valve to prevent backflow (SS636)
Proper drainpipe connection for safe water discharge
Upgraded electrical wiring with earth bonding for safety (CP5)
New stainless steel hot and cold water piping within 1 metre

Work Scope for Water Heater Corrosion Replacement

Removal & Site Prep

Shut off the water and power supply
Safely removed the corroded Joven JH15 unit
Disconnected non-compliant fittings

Installation of Joven JSH25

Mounted new 25L JSH25 securely
Installed stainless steel inlet/outlet pipework
Fitted double check valve, drainpipe, and stop valve
Applied protective electrical bonding
Recommissioned the system and tested for leaks and safety

Testing & Commissioning

Leak testing and pressure validation
Bonding continuity check
Verified safe operation of temperature relief valve and new drainage line

Documentation

Submit the required documents to PUB by a PUB-licensed plumber

Conclusion

This water heater corrosion case at 76A Redhill Road HDB posed multiple hazards, from tank failure and water backflow to potential electrocution due to missing bonding. Homeone’s replacement with a Joven JSH25 and full safety upgrades ensures the homeowner now enjoys a PUB-compliant, leak-free, and safe water heater installation.

All work was carried out under the supervision of a PUB-licensed plumber and EMA-certified electrician

Project Location: 76A Redhill Road HDB

76A Redhill Road HDB