Navien Error Code E016 — Overheating Repair in Greater Vancouver
A Navien boiler showing E016 has overheated — the heat exchanger reached an abnormal high temperature and the unit shut down for protection. It almost always comes down to restricted water flow, frequently from scale in the heat exchanger. ROMA Heating & Cooling resolves recurring E016 faults at the root across Greater Vancouver, since 1999.
What Causes a Navien E016
- Scale build-up in the heat exchanger — hard-water mineral deposits restrict flow and trap heat.
- Failing circulation pump — cannot move water fast enough through the exchanger.
- Trapped air — air pockets block proper circulation.
- Closed or partly closed valve — restricts the flow rate.
- Low system pressure — reduces effective circulation.
What You Can Safely Do
- Check system pressure is around 1 to 1.5 bar; top up if low.
- Make sure isolation valves under the boiler are fully open.
- Reset once. If E016 returns, book service rather than repeatedly resetting.
How ROMA Repairs E016
We descale and flush the heat exchanger, test and replace the circulation pump if needed, bleed trapped air, verify flow and pressure, and confirm temperatures stay safely in range under full load — preventing the fault from returning.
What Our Customers Say
“Nelson arrived on time and quickly diagnosed the boiler issue.”
— Cynthia Lim, Google review (★★★★★)
“My Viessmann Boiler 100-W stopped working on Wednesday. We called ROMA, the technician came on Thursday and found the issue.”
— Qiming Zhong, Google review (★★★★★)
Frequently Asked Questions
What does Navien E016 mean?
E016 is an overheating / abnormal high-temperature fault — the heat exchanger ran hotter than allowed and the boiler shut down to protect itself.
What causes a Navien E016?
Low water flow is the usual culprit: scale build-up in the heat exchanger, a failing circulation pump, trapped air, or a closed valve restricting flow.
Does hard water cause E016?
Yes — mineral scale from hard water narrows the heat exchanger passages and restricts flow, a common cause of repeat E016 faults in parts of Greater Vancouver.
How do you fix a recurring E016?
We descale and flush the heat exchanger, test the pump and flow, bleed trapped air, and confirm temperatures stay in range under load.
Can I keep using the boiler with E016?
It will keep locking out to protect itself. Continuing without fixing the flow restriction risks heat-exchanger damage, so have it diagnosed.
Related Navien & Boiler Services
- Navien Boiler Error Codes (Full Guide)
- Navien Boiler Repair
- Navien Heat Exchanger Error Repair
- Navien E003 Ignition Failure Repair
- Navien E012 Flame Loss Repair
- Boiler Pressure Issues Repair
Navien Showing This Code? Call ROMA
Resetting clears the lockout but not the cause — the code will return until the fault is fixed. For accurate Navien diagnosis and repair with genuine OEM parts, call (604) 704-0300 or email info@romaheating.ca. Same-day service across Greater Vancouver, gas-licensed since 1999.
What Greater Vancouver Homeowners Say
“Nelson worked hard to get the NTI unit fixed. He was always polite, courteous and on time.”
“As always Nelson was super efficient. Showed up on time and was quick to work. I had a full maintenance done on the fireplaces and furnace. He was awesome. I won’t use anyone else.”
“Excellent service. Andy had a spare Carrier inducer with him which saved us time.”
“Was very prompt to respond to our issues. Technician was scheduled for the day following my initial call.”
“Very professional heating company. Price is reasonable, excellent work.”
“Highly recommend this company. It was a pleasure dealing with Shawn and Nelson.”
“Professional and courteous technicians with attention to detail and customer needs.”
“Always great, friendly service. Serviced the hot water on-demand system. Honest and informative. Thanks!”
“Speedy response time, honest, and professional service from start to finish.”
Why Greater Vancouver Trusts ROMA Heating & Cooling
ROMA Heating & Cooling has installed, repaired and maintained heating and cooling systems across Metro Vancouver since 1999. Our team are TSBC-licensed gas fitters (Gas LGA0202903) and Red Seal-trained technicians — licensed, bonded and insured — and we back every job with upfront, flat-rate pricing and a 100% satisfaction guarantee. We hold a 4.8★ rating from 221+ Google reviews.
- Authorized for 30+ brands (Lennox, Carrier, Viessmann, Navien, Rheem & more)
- Upfront flat-rate pricing — no overtime or hidden fees
- Free, no-obligation estimates on new installations
- Locally owned & operated in Burnaby, BC
No Hidden Fees
Our service rates are transparent and easy to understand. You approve upfront, flat-rate pricing before we start — so you never get a bill you didn’t expect.
Licensed & Bonded
ROMA is a TSBC-licensed gas contractor (Gas LGA0202903). Our technicians are bonded, insured and Red Seal-trained — qualified for any heating or cooling system.
Free Estimates
We offer free, no-obligation estimates on new installations — furnaces, boilers, heat pumps, air conditioners, tankless and hot-water tanks.
ROMA Heating & Cooling is a trusted HVAC contractor serving Metro Vancouver since 1999. We specialize in furnace repair, heat pump installation, boiler services, air conditioning, and emergency heating solutions for residential, commercial, and government clients. Available 24/7, our certified technicians deliver fast, reliable, and affordable HVAC services across Greater Vancouver.