Product Information
Description
Hayward HPX51100122201 HeatPro and Summit Heat Pump Control Board Retrofit Kit
Bring the brain of your heat pump back.
The Hayward HPX51100122201 Heat Pump Control Board Retrofit Kit (PST-HPX51100122201) is the genuine Hayward OEM replacement brain for HeatPro, Summit, HeatMaster, EnergyTherm, and EasyTemp pool heat pumps. You get the updated electronic control board assembly that supersedes the legacy SMX306000016, with the same plug-in connector layout your installed harness already uses. Drop it in, restore the temperature setpoint, fault codes, and compressor staging, and skip the cost of replacing the entire heat pump cabinet.
Restores Smart Control to Your Heat Pump
When the original board faults, the heat pump stops staging, stops reading the water temperature sensor, or throws a blank display. The HPX51100122201 drops in as a direct OEM replacement and brings back setpoint control, defrost cycling, high and low pressure protection, and the fault-code readout. You skip a several-thousand-dollar full-cabinet swap and put the existing compressor, fan, and titanium heat exchanger back to work for the rest of the season.
Replaces the Legacy SMX306000016
Hayward consolidated the older SMX306000016 board into the updated HPX51100122201 retrofit kit, which uses the same harness connectors your installed unit already has. The pin-outs for the high-pressure switch, low-pressure switch, water temperature sensor, ambient sensor, defrost sensor, and contactor coil land on the same headers, so a qualified service tech can swap the board without re-pinning the harness or rebuilding the low-voltage tree.
Fits Hayward HeatPro and Summit Lines
One board covers the residential Hayward heat pump catalog from the Summit and HeatPro families through HeatMaster, EnergyTherm, and EasyTemp. That includes HP21004T, HP21124T, HP21254T, and HP21404T HeatPro units, the SUM-series Summit heat pumps, and the larger HP31154T and HP31204T variants. Verify your unit's model and serial label, and confirm the legacy board number against SMX306000016 before ordering.
Who It's For
HeatPro Heat Pumps
Direct replacement on HP21004T, HP21124T, HP21254T, and HP21404T HeatPro residential pool heat pumps when the original board faults or displays go dark.
Summit Heat Pumps
Brings the SUM5, SUMXL112, SUMXL140, and other Summit-series units back to full setpoint and defrost control without replacing the entire cabinet.
HeatMaster and EnergyTherm
Carries forward into HeatMaster, EnergyTherm, and EasyTemp residential heat pumps that share the legacy SMX306000016 board footprint.
End-of-Season Repairs
Common spring-startup fix when the heat pump powers on but will not stage the compressor, will not read water temperature, or trips a board-side fault code.
Why PST Customers Pick This
Genuine Hayward OEM
Built and packaged by Hayward, not a third-party clone. Maintains your unit's eligibility for any remaining manufacturer service support.
Plug-In Connector Retrofit
Drops onto the existing harness headers used by the SMX306000016, so the swap is a board exchange, not a harness rebuild.
Full Sensor Support
Reads the water, ambient, and defrost temperature sensors and drives compressor staging and defrost cycling per Hayward's logic.
High and Low Pressure Protection
Honors the refrigerant high-pressure and low-pressure switches so the compressor faults out cleanly instead of running into damage.
Covers Multiple Heat Pump Families
One part number serves the HeatPro, Summit, HeatMaster, EnergyTherm, and EasyTemp lines, simplifying the parts shelf for service pros.
Restores Fault Code Diagnostics
Returns the on-board fault display so the next service call diagnoses the unit in minutes instead of chasing voltages with a meter.
Installation Notice
The HPX51100122201 is a line-voltage and low-voltage control board inside a pool heat pump. Disconnect power at the breaker before opening the cabinet and verify zero voltage at the contactor load side. Installation must be performed by a qualified HVAC or pool heat pump technician, and all bonding, grounding, and disconnect work must comply with NEC 680. Improper installation, miswired sensor leads, or reversed line voltage will damage the board and void Hayward's warranty.
Full Specifications
Frequently Asked Questions
Does the HPX51100122201 actually replace the SMX306000016?
Yes. Hayward superseded the older SMX306000016 with the HPX51100122201 retrofit kit, and the new board uses the same harness connectors. If your old board is stamped SMX306000016 and the heat pump model is on the compatibility list, the HPX51100122201 is the correct replacement.
Which Hayward heat pump models is this control board compatible with?
The HPX51100122201 covers the HeatPro models HP21004T, HP21124T, HP21254T, and HP21404T, the Summit series including SUM5, SUMXL112, SUMXL140, HP31154T, and HP31204T, and the related HeatMaster, EnergyTherm, and EasyTemp residential heat pumps. Always cross-check the legacy board number on the old board and your unit's model and serial label before ordering.
How do I know the board is the actual problem and not the sensor or contactor?
Common symptoms that point to the board are a blank or frozen display, a unit that powers on but never calls the compressor contactor, missing temperature reads from a known-good sensor, or repeating fault codes that clear when the board is reset but return immediately. Replace the board only after a service tech has confirmed line voltage at the input, verified the sensors with a meter, and ruled out the contactor coil. Hayward will not warranty a board damaged by an unaddressed sensor or wiring fault.
What is the difference between this kit and a generic aftermarket board?
The HPX51100122201 is a genuine Hayward OEM board produced for retrofit service. Aftermarket clones may map the connectors differently, may not honor the high and low pressure switch logic, and will not be covered by Hayward's warranty if they damage the compressor. PST sells only the OEM Hayward kit.
Can I install this myself?
No. The board sits inside a high-voltage cabinet next to a single-phase or three-phase contactor and a sealed refrigerant system. Replacement must be performed by a qualified pool heat pump or HVAC service technician, with power disconnected at the breaker and verified at the load side. Wiring, bonding, and grounding must comply with NEC 680. PST does not warranty boards damaged by owner installation or by miswired sensor or contactor leads.
Does it come with the sensors, harness, or display ribbon?
The HPX51100122201 retrofit kit is the electronic control board assembly. Reuse your existing temperature sensors, pressure switches, harness, and display ribbon if they test good. If a sensor or pressure switch is the root cause of the original board failure, order the corresponding Hayward service part and replace it at the same time.
What warranty does PST offer on this Hayward control board?
Hayward backs the HPX51100122201 with a 1-year parts-only limited warranty from the date of purchase, registered through PST Pool Supplies as an authorized Hayward dealer. Damage from miswired sensors, line-voltage faults, or owner installation is not covered.
Order the Hayward HPX51100122201 From PST
Authorized Hayward dealer. PST ships the genuine OEM HPX51100122201 retrofit control board with full Hayward manufacturer warranty registered through PST Pool Supplies.
Additional Info
| Category | Parts Pool Parts Pool Heater Parts |
| SKU | PST-HPX51100122201 |
| MPN | HPX51100122201 |
| Manufacturer | Hayward |
| Weight | 0.0 lb |
Let customers speak for us
Easy to order - received the next day!
Beautiful!!
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Great product does exactly what was advertised to do.
I ordered the wrong part. Customer service was very helpful. I returned it and within the week my credit card was credited back. Excellent customer service policy.
There was a delay in shipping due to postal service. They sent another part right away.
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Exactly as advertised and super fast shipping and delivery
