DIY Error Codes

Pentair MasterTemp gas pool heater Error ERR PS

Not enough water flow (pressure switch). Pentair says ERR PS indicates insufficient water flow to the heater.

Make sure the pump is running and clean the filter and skimmers. If ERR PS stays on, call a qualified technician.

Start the fix →When to call a pro ↓
Full answer & models

Pentair MasterTemp ERR PS means not enough water flow (pressure switch). Check the pump, filter and skimmers; if it stays, call a technician.

Applies to: MasterTemp 175K (460792, 460793)MasterTemp 200K (460730, 460731, 461000, 461001, 461032)MasterTemp 250K (460732, 460733, 460771, 460772, 460806, 461020)MasterTemp 300K (460734, 460735)MasterTemp 400K (460736, 460737, 460775, 460776, 460805, 461021)
Also searched as: Pentair heater PS error, MasterTemp ERR PS, Pentair pool heater PS

Gas appliance. Service only by a qualified technician.
Why
Pentair, what to do if you smell gas: do not try to light any appliance; do not touch any electrical switch and do not use any phone in your building; immediately call your gas supplier from a neighbor's phone. Pentair: this product must be installed and serviced by authorized personnel qualified in pool/spa heater installation; improper installation or operation can create carbon monoxide and flue gases that can cause serious injury or death. Pentair warning: risk of explosion or fire causing burns or death if safety interlocks are disabled. Do not operate the heater when ERR HLS, ERR AFS, ERR IGN, ERR AGS, ERR SFS, E01, E05, E06 or 126 is displayed; shut down the heater ("To turn off gas to appliance", page 43) and have a qualified service technician check the system.

What PS means

Not enough water flow (pressure switch). Pentair says ERR PS indicates insufficient water flow to the heater.

More detail
Pentair's MasterTemp Installation and User's Guide (Table 8, Heater Error and Fault Codes, page 48) lists ERR PS as "Water pressure switch open". Pentair says ERR PS indicates insufficient water flow to the heater. Pentair: if water flow is established the error clears and normal operation resumes.

5-minute checks

Fix it step by step

Step 1 of 3

  1. Make sure the pump is running

    • 2 min
    • None
    • DIY

    Safety: Gas appliance. Service only by a qualified technician.

    The pressure switch senses that the pump is running.

    More detail

    Make sure the pump is running.

    Pentair: the pressure switch (PS) senses that the pump is running. With no water flow the heater shows ERR PS.

    Did the code clear?

  2. Clean the filter and skimmers

    • 20 min
    • None
    • DIY

    Pentair's owner-level fix for ERR PS.

    More detail

    Clean the filter and skimmers.

    Pentair (page 45): if the pump is operating, ERR PS usually indicates that the filter and/or skimmers should be cleaned (some filters may require back-washing). The error clears once water flow is established.

    Did the code clear?

  3. Call a qualified service company

    • Decision
    • None
    • Pro decision

    Stop here and book a qualified technician.

    More detail

    Call a qualified service company.

    Pentair's manual says only qualified, trained service technicians with appropriate test equipment should service the heater. Pentair: if the message remains on after the filter and skimmers have been serviced, the system should be checked by a qualified service technician.

    Still showing PS?Need a pro → call a pro

Code cleared. Nice work.

Watch the display for a day to make sure it stays clear.

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Fixed after any step? Watch the display for a day to make sure it stays clear. Still PS after step 3? call a pro.

Call a pro if…

  • You smell gas (leave first, then call your gas supplier from a neighbor's phone).
  • ERR PS is displayed and does not clear, or keeps returning.
  • Anything inside the heater cabinet, wiring, or the gas valve.

FAQ

What does ERR PS mean on a Pentair MasterTemp?

"Water pressure switch open", per Table 8 of the MasterTemp manual. Pentair says ERR PS indicates insufficient water flow to the heater.

Will ERR PS clear by itself?

Yes. Per Table 8, if water flow is established the error is cleared and normal operation resumes.

Source: Pentair MasterTemp Pool and Spa Heater Installation and User's Guide, Table 8 Heater Error and Fault Codes and Troubleshooting, pp. 45, 48 and 53. Written by the DIY Error Codes team. Updated 2026-10-16. DIY Error Codes is independent and not affiliated with or endorsed by Pentair.