Balboa spa error codes and panel messages

Short answer

Balboa BP systems number each message from M015 to M044. M016 and M017 mean low flow through the heater, M027 and M028 a dry heater, and M029 and M030 overheat: 110°F in the spa water or 118°F inside the heater. Smaller panels show the same faults as letters: HFL, LF, dr, OHS and OHH.

Updated October 2026By the HotTubFinder research desk

A hot tub control panel showing an error code, and the owner's manual, which names the control system — The panel shows the code. Its label is often the spa's brand, so check the manual for the control system.

What you can check yourself

Check the water level and top it up to the line in your manual.
Clean the filter, or replace it if it is worn.
Open any closed valves and jets.
Purge an air lock the way your owner's manual describes.
Clear the message on the panel once the cause is fixed.

Where the owner's part ends

Anything else: turn off power at the breaker and call a technician.

Balboa's own flow checklist is low water, suction blockages, closed valves, trapped air, too many closed jets and pump prime. Anything past that is a service call.

Balboa BP message codes M015 to M044, from Balboa's TP400/TP600 user guide

20 codes

Balboa BP message codes M015 to M044, from Balboa's TP400/TP600 user guide
Code	What it means	What to do
M015	Panel: Sensors are out of syncThe two temperature sensors in the heater may disagree by 2 to 3°F. Balboa says to call for service.	Technician Call for service if it does not clear within a few minutes.
M016Also: HFL	Panel: The water flow is lowNot enough water is moving through the heater to carry the heat away. The heater waits about a minute and tries again.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Call if it keeps coming back after the checks.
M017Also: LF	Panel: The water flow has failedFlow through the heater stayed too low and the heater has been switched off. It stays off until you clear the message.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Clear the message on the panel once the cause is fixed. Call if it returns after the checks and one reset.
M019	Panel: Priming modeNormal at every power-up. For 4 minutes you can run each pump to push air out; the heater stays off until priming mode ends.	Normal Nothing to do: this is the spa working as designed.
M020	Panel: The clock has failedThe clock that keeps time while the spa is off has failed.	Technician Contact your dealer or service company.
M021	Panel: The settings have been resetPersistent memory was reset, which is normal after a setup change.	Normal Clear the message on the panel once the cause is fixed. Call if it shows on more than one power-up or after normal running.
M022	Panel: Program memory failureThe control failed its firmware check at power-up.	Technician Needs a service call.
M026	Panel: Sensors are out of sync, call for serviceThe heater's two sensors have disagreed for at least an hour.	Technician Call for service.
M027	Panel: The heater is dryThere is not enough water in the heater to start it, so the spa is shut down until the message is cleared.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Clear the message on the panel once the cause is fixed. Call if it comes back after the checks.
M028Also: dr	Panel: The heater may be dryThe heater may be dry or short of water. The spa shuts down for 15 minutes, then tries again.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Call if it repeats after the checks.
M029Also: OHS	Panel: The water is too hotA sensor read 110°F (43.3°C) in the spa water and spa functions stop. It resets on its own below 108°F (42.2°C). Long pump runs or hot weather can cause it.	Stay out Stay out of the water. Take the cover off so the water can cool. Call if it does not reset once the water cools, or keeps happening.
M030Also: OHH	Panel: The heater is too hotA sensor read 118°F (47.8°C) inside the heater and the spa shut down. It can be cleared only once the water is below 108°F (42.2°C).	Stay out Stay out of the water. Take the cover off so the water can cool. Clean the filter, or replace it if it is worn. Check the water level and top it up to the line in your manual. Open any closed valves and jets. Call if it happens again after one reset.
M031	Panel: Sensor A faultTemperature sensor A or its circuit has failed.	Technician Call for service.
M032	Panel: Sensor B faultTemperature sensor B or its circuit has failed.	Technician Call for service.
M033	Panel: Safety trip, pump suction blockageThe vacuum switch closed because of a suction problem or a possible entrapment. Not every spa has this switch.	Stay out Stay out of the water. Turn off power and call for service.
M034	Panel: A pump may be stuck onA pump appears to be stuck running, and the water may be overheating.	Stay out Stay out of the water. Power down the spa and call for service.
M035	Panel: Hot faultA pump appears to have been stuck on when the spa was last powered.	Stay out Stay out of the water. Power down the spa and call for service.
M036	Panel: The GFCI test failedNorth America only. The system could not test or trip the GFCI, which may mean an unsafe installation.	Technician Contact your dealer or service company.
M037	Panel: Hold modeHold mode turns the pumps off for service jobs such as cleaning or replacing the filter. It lasts 1 hour unless you exit it.	Normal Nothing to do: this is the spa working as designed.
M044	Panel: J29 warningJ29 is a heater-disable input on the control board. The message shows if it is shorted at power-up.	Technician Contact your dealer if it appears after several power-ups.

M044 comes from the Balboa TP200 pages in Cal Spas' 2026 manual. Each dot opens the source at its page.

What do Balboa's letter codes mean?

They are the same faults on panels with fewer characters. Balboa's user guide pairs them: HFL is M016, LF is M017, dr is M028, OHH is M030 and OHS is M029. Its service manual adds that one panel style shows HL for the low-flow message and Sn for sensor sync. So on a Balboa tub, HL is a flow warning, not a high-limit trip. HL means something else on Gecko.

Balboa panel abbreviations and the faults they stand for

9 codes

Balboa panel abbreviations and the faults they stand for
Code	What it means	What to do
HFLAlso: HL, HTR FLOW LOSS	Panel: Heater flow is reducedLow flow through the heater during heating; the heater retries after about a minute. Same fault as M016. Balboa's service manual lists HL as another panel's name for it.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Call if it keeps returning.
LFAlso: HTR FLOW FAIL	Panel: Heater flow failedPersistent low flow: the heater is off but the rest of the spa runs. Same fault as M017. On Balboa's VL panels it shows after the fifth flow-loss message within 24 hours.	Check first Check the water level and top it up to the line in your manual. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Purge an air lock the way your owner's manual describes. Clear the message on the panel once the cause is fixed. Call if it returns after the checks.
drAlso: HTR MAY BE DRY	Panel: Heater may be dryPossible dry heater, poor flow or air bubbles in the heater. The spa shuts down for 15 minutes. Same fault as M028.	Check first Check the water level and top it up to the line in your manual. Purge an air lock the way your owner's manual describes. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Call if it repeats after the checks.
OHHAlso: HTR TOO HOT	Panel: Heater is too hot118°F (47.8°C) inside the heater; the spa shuts down until the water is below 108°F and the message is cleared. Same fault as M030.	Stay out Stay out of the water. Take the cover off so the water can cool. Clean the filter, or replace it if it is worn. Open any closed valves and jets. Call if it happens again after one reset.
OHSAlso: WATR TOO HOT	Panel: Water is too hot110°F (43.3°C) in the spa water; functions stop until it falls below 108°F. Same fault as M029.	Stay out Stay out of the water. Take the cover off so the water can cool. Call if it keeps happening.
SnSAlso: Sn, SENSOR SYNC	Panel: Sensors out of syncThe two heater sensors read 2°F or more apart when not heating. Balboa's service manual notes the same reading can also trigger the flow messages.	Technician Call for service.
ICE	Panel: Potential freezeA freeze risk was detected and the equipment turns on by itself. It stays on 4 minutes after the water is back to 45°F (7.2°C).	Normal Nothing to do: this is the spa working as designed.
Ecn	Panel: Economy modeEconomy mode. The pump can be off for hours outside a filter cycle, so Ecn shows solid while the temperature reading is not current and alternates with it once it is.	Normal Nothing to do: this is the spa working as designed.
SLP	Panel: Sleep modeSleep mode, set from the panel. As with Ecn, the pump can be off for hours outside a filter cycle, and SLP shows solid while the temperature reading is not current.	Normal Nothing to do: this is the spa working as designed.

How does a Balboa heater decide the flow is low?

It compares two sensors. Balboa's M7 heaters have a sensor at each end of the element instead of a pressure switch. Before heating, the pump runs at least 2 minutes and the two readings must be within 2°F. The heater then fires for 6.5 to 18 seconds and rests 90 seconds. Good flow keeps the temperature rise small; a big or long rise means little or no water, and the control throws a flow or dry message.

That is why a dirty filter or an air lock after a refill shows up as a heater message. The heater is fine; the water just is not getting through it fast enough.

Why does the message change if I ignore it?

Balboa steps up the response. On its VL panels a low-flow warning repeated five times in 24 hours becomes LF, and the heater stays off until you clear it. A dr message shuts the spa down for 15 minutes; the third one in a row becomes the dry message and the spa will not restart by itself. Clearing it without fixing the flow only starts the count again.

More on each step: cleaning the filter and filling and starting a hot tub.

Which hot tub brands use Balboa's codes?

These manuals print Balboa's list or name Balboa equipment. Marquis prints the same M0xx numbers and meanings without naming the control maker. Check your own manual before you rely on a code.

Which code list each brand's manual uses, by model line
Brand	Model line, what its manual shows, and the code list
Bullfrog Spas	2014 modelsBalboa BP packs; the manual's panel pages are Balboa's, with M0xx message codes.Code list: Balboa BP systems with TP panels (message codes)
Master Spas	Getaway, 2026Balboa VS500Z pack with a VL400-family panel.Code list: Balboa panel abbreviations
Cal Spas	Models with Balboa equipment, 2026Balboa's TP200 message list with MO-numbered codes.Code list: Balboa BP systems with TP panels (message codes)
Marquis	Crown Collection, 2026Prints the same M0xx numbers and meanings as Balboa's BP list.Code list: Balboa BP systems with TP panels (message codes)
PDC Spas	Hot tubs, 2026Spec tables name Balboa 501X1, 100X1 and 100NX packs; M0xx messages.Code list: Balboa BP systems with TP panels (message codes)
Nordic Hot Tubs	2024 modelsRefers owners to Balboa's TP200 and TP500S user guides; Pr is priming mode.Code list: Balboa BP systems with TP panels (message codes)
Artesian Spas	South Seas SpasSame messages and temperatures as Balboa's VL panels; Pr is priming.Code list: Balboa panel abbreviations

Common questions

What does M015 mean on a Balboa hot tub?

Sensors are out of sync: the two temperature sensors in the heater may disagree by 2 to 3°F. If it lasts an hour it becomes M026. Balboa says to call for service.

What is the difference between M016 and M017?

Both mean too little water is moving through the heater. M016 is a warning and the heater tries again after about a minute. M017 means the heater has been switched off until you clear the message.

What do M029 and M030 mean?

Overheat. M029 is spa water at 110°F (43.3°C) and resets itself below 108°F. M030 is 118°F (47.8°C) inside the heater, and you clear it once the water is under 108°F. Stay out of the water for both.

How do I clear a Balboa error message?

Balboa marks the messages you can clear with a button press once the cause is fixed: M017, M021, M027 among others. Sensor, memory and stuck-pump messages need a technician.

What does M019 or Pr mean on a Balboa spa?

Priming mode. It runs for 4 minutes at every power-up so you can run each pump and push the air out, and the heater stays off until it ends. Some manuals for Balboa-equipped tubs, such as Nordic's 2024 manual, show it as Pr.

Sources

Balboa TP400/TP600 user guide (40940_N), panel messages balboawater.com · checked October 2026
Cal Spas Patio and Patio Plus owner's manual, Balboa equipment, 2026 calspas.com · checked October 2026
Balboa troubleshooting and service manual for EL/VS systems balboawater.com · checked October 2026
Getaway Hot Tubs owner's manual, 2026 (Master Spas) masterspascdn.com · checked October 2026
Balboa VL401 user guide (40789_G), diagnostic messages balboawater.com · checked October 2026
Balboa panel message reference guide (40922 rev B) balboawater.com · checked October 2026
Balboa BP troubleshooting and service manual, 60 Hz balboawater.com · checked October 2026
Nordic Hot Tubs owner's manual, January 2024 nordichottubs.com · checked October 2026
Bullfrog Spas owner's manual, 2014 bullfrogspas.com · checked October 2026
Marquis Crown Collection owner's manual, 2026 marquisspas.com · checked October 2026
PDC Spas hot tub owner's manual, 2026 media.cmsmax.cloud · checked October 2026
Artesian Spas South Seas Spas owner's manual artesianspas.com · checked October 2026

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