12-Year-Old Hayward Pool Heater Replaced in Ancaster After Heat Exchanger Leak
Recently, AirPro Heating & Cooling completed a pool heater replacement in Ancaster, Ontario, after a 12-year-old Hayward pool heater developed a water leak caused by a failed heat exchanger.
The existing heater was a Hayward H250C, a 250,000 BTU natural-draft pool heater that had been operating for approximately 12 years. It was installed inside a shed and used a natural-draft venting system with a draft hood and millivolt gas valve.
After the heat exchanger developed a leak, the homeowner decided to replace the aging pool heater with a new Hayward H250FDN.
The Problem: A Leaking Heat Exchanger
During the inspection, we found that the existing Hayward H250C was leaking water from the heat exchanger.
The heater had been in service for approximately 12 years. The water leak was not caused by a simple connection or plumbing issue—the heat exchanger itself had failed.
The original H250C installation included:
Hayward H250C pool heater
250,000 BTU input
Natural-draft combustion
Draft hood
Millivolt gas valve
7-inch venting
Installation inside a shed
Because the heat exchanger is a major component of a gas pool heater, the age and overall condition of the existing equipment were important factors when considering repair versus replacement.
In this case, the homeowner chose to replace the entire heater with a new Hayward H250FDN.
Hayward H250C to H250FDN Replacement
The old Hayward H250C was removed and replaced with a new Hayward H250FDN.
Although both heaters are rated at approximately 250,000 BTU, the new heater uses a different combustion and venting design.
The original H250C used a natural-draft system with a draft hood and millivolt gas valve.
The new H250FDN uses electronic ignition and forced-draft combustion.
Because of this difference, the existing draft hood was removed and the venting configuration was changed to match the new heater.
A new vent adapter was installed as part of the replacement.
7-Inch to 6-Inch Venting
One of the noticeable changes during this installation was the change in vent size.
The original 250,000 BTU natural-draft H250C used a 7-inch vent.
The new 250,000 BTU Hayward H250FDN uses a 6-inch venting configuration for the negative-pressure indoor vent application.
The change from 7 inches to 6 inches was therefore part of the equipment change from the older natural-draft system to the new forced-draft system. It was not simply a reduction in vent size.
The existing draft hood was removed, and the appropriate vent adapter was installed for the new H250FDN.
Hayward's installation documentation specifies a 6-inch vent for the H250FD model in the negative-pressure indoor vent configuration. The manufacturer also provides specific requirements for vent sizing, vent height, lateral length, elbows, clearances, and termination.
New Hayward H250FDN
The replacement unit is a Hayward H250FDN 250,000 BTU pool heater.
Compared with the 12-year-old H250C, the new heater features a modern electronic ignition and forced-draft combustion system.
The H250FDN is rated at 84% thermal efficiency.
The new installation included:
New Hayward H250FDN pool heater
250,000 BTU input
Electronic ignition
Forced-draft combustion
New vent adapter
6-inch negative-pressure venting configuration
Removal of the old natural-draft draft hood
The new heater was installed and the system was checked to ensure the pool heating equipment was operating properly.
Old vs. New Pool Heater
Existing System | New System |
Hayward H250C | Hayward H250FDN |
Approximately 12 years old | New installation |
250,000 BTU | 250,000 BTU |
Natural draft | Forced draft |
Millivolt gas valve | Electronic ignition |
Draft hood | New vent adapter |
7-inch vent | 6-inch vent |
Leaking heat exchanger | New heat exchanger |
Older installation | 84% thermal efficiency |
Why the Heat Exchanger Leak Led to Replacement
A pool heater's heat exchanger is responsible for transferring heat from the combustion process to the pool water.
When a heat exchanger develops a leak, water can escape from the heater and the unit may no longer be suitable for continued operation.
On a relatively new pool heater, replacing a heat exchanger may be one option worth considering. However, this particular heater was approximately 12 years old.
The homeowner therefore chose to replace the complete heater rather than invest in a major repair on an aging unit.
The replacement also provided an opportunity to move from the older natural-draft and millivolt configuration to a newer electronic ignition and forced-draft system.
This Ancaster installation is another example of a pool heater replacement where the cause of the problem was identified before deciding on the repair or replacement approach.
The original Hayward H250C had provided approximately 12 years of service before its heat exchanger began leaking.
The replacement involved more than simply disconnecting the old heater and connecting a new one. Because the old and new heaters use different combustion and venting designs, the draft hood and venting configuration also had to be changed.
The result was a new Hayward H250FDN with electronic ignition, forced-draft combustion and the appropriate 6-inch negative-pressure venting configuration.
Pool Heater Repair and Replacement in Ancaster
AirPro Heating & Cooling provides pool heater repair, troubleshooting and replacement in Ancaster, Hamilton and surrounding areas.
If your pool heater is leaking water, failing to heat the pool, having ignition problems, or approaching the end of its service life, a proper inspection can help determine whether repair or replacement is the appropriate option.
For more information about pool heater service in Ancaster, visit our Pool Heater Repair in Ancaster service page.
Service Areas: Ancaster, Hamilton, Dundas, Stoney Creek, Burlington and surrounding communities.
Pool Heater Services: Pool Heater Repair • Pool Heater Troubleshooting • Pool Heater Replacement
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