Skip to main content
SuncoastPool Solutions
Menu
941-961-9337

Pool-heater brand guide

Rheem gas pool heaters

Smell gas or hear a CO alarm? Leave first.

If you smell gas, a carbon monoxide (CO) alarm sounds, or anyone may have symptoms of CO poisoning, leave first and call 911 from a safe place. Do not use switches, phones, or anything that could make a spark nearby. Then call your gas utility or propane company.

See all safety steps

Look up a message by model

Yes, Suncoast repairs and installs Rheem gas pool heaters that run on natural gas or propane. We work at homes in Sarasota and Manatee Counties. You do not need to find a Rheem-only shop. Call with the model on the label. Colin confirms the exact model and your address before he books the work. Suncoast is an independent service company. We are not a Rheem authorized dealer, warranty center, or manufacturer-certified service provider.
Call Colin941-961-9337

Call Colin at 941-961-9337. There is no online form on this page. Keep the cabinet closed and use only the visible details described below.

From model to message to next step

Follow these steps in order. Use the links to jump to the part of this page that helps.

  1. Check for danger firstGas smell, smoke, fire or a CO alarm? Leave and call from a safe place. Skip the rest.Safety steps
  2. Find the modelRead it from the label on the outside of the heater. Do not open a panel.Model list
  3. Copy the messageWrite every letter and space. Note if it is steady or flashing, and if it came from the heater, a control system or an app.
  4. Match bothFind your model, then your message. No match? Do not borrow a meaning from another model.Message lookup
  5. Take the next safe stepNote only what you can see from where you stand. Then call Colin with the model and the message. A technician finds the cause.

Rheem repair

Say what the heater is doing. If it has a display, read any message word for word. That message helps Colin prepare. It does not name the failed part. He checks the heater, the water flow and the gas supply on site. He explains what he found and gives you a price. Pool heater repair

Rheem replacement or new install

A new heater has to fit your gas supply, pad, plumbing and controls. Colin reviews those before he quotes. Your replacement does not have to be a Rheem. That choice comes after the review. Installation and replacement

Which Rheem heater do you have?

On October 14, 2026, Rheem's pool and spa heater page listed these gas heaters:

  • AVIA and AVIA with NiTek. Model numbers start with P-M264 or P-M404.
  • Digital and Millivolt. Model numbers start with P-M206, P-M266, P-M336 or P-M406.
  • Above Ground 106 (P-M106A), with dial controls. See the Above Ground 106 page.
  • Above Ground 156 (P-M156A), with a digital control. See the Above Ground 156 page.

The letters at the end of a Rheem model number change between versions. Copy the whole number from the label.

What does a Rheem heater message mean?

Rheem gas pool heaters with a digital control show short phrases, such as Water Sw Open. Some phrases are normal, like No Demand. Others report a fault. A phrase points to what the heater sensed, not to a failed part. Millivolt models and the Above Ground 106 have no message screen. The message lookup below explains each phrase by model, with the manual page.

Millivolt models have a standing pilot, a small flame that stays lit. You set them with a thermostat dial. If the pilot goes out, a safety part shuts off the gas to the burner and the pilot (Digital and Millivolt manual, pp. 6, 26 and 33). If your pilot keeps going out, ask a technician to check it. The Above Ground 106 has a dial. The 156 has a digital control (Above Ground manual, pp. 16 to 17).

Message lookup by model

Find your model, then your message. Each card gives the exact words, what they mean, what the manual checks, what you can safely note, and the page it comes from. A message is a clue. It does not prove which part failed. A call for heat is when the control asks the heater to warm the water. Lockout means the heater stops trying for a set time or until it is reset.

Rheem Digital (P-M206A to P-M406A, E models)

In a Rheem model number, E means electronic ignition with a digital control. M means millivolt, with a standing pilot and a dial.

Heating, Spark or No Demand

Normal
Applies to
Rheem Digital (E) models, not Millivolt
What it means
No fault is active.
What the manual checks
None needed.
What you can safely note
Note which one you see.
Technician's part
Not needed for these messages alone.

Water Sw Open

Fault
Applies to
Rheem Digital (E) models, not Millivolt
What it means
The water pressure switch is open while the heater is asked to heat.
What the manual checks
The manual has an owner list for a heater that will not fire. It starts with the time clock and a full pump strainer basket. Next come a dirty filter and a pump that has lost its prime (stopped moving water).
What you can safely note
Follow only the owner steps in your pump and filter manuals.
Technician's part
Ask a technician about everything else on the list.

Clock/Fireman Sw

Status
Applies to
Rheem Digital (E) models, not Millivolt
What it means
The time clock or fireman switch circuit is open. A time clock connects to the heater through this circuit. When a time clock is wired in, the manual says this shows when the clock has turned off the call for heat.
What the manual checks
The manual lists it with the active faults. Its time clock note explains why it can be expected.
What you can safely note
Is a timer or pool control set to stop heating at this time?
Technician's part
If it shows when the clock should be calling for heat, ask a technician. Do not check the wiring yourself.

Main Ign Failure

Fault
Applies to
Rheem Digital (E) models, not Millivolt
What it means
The pilot flame went out while the heater was trying to light the main burner. On a Digital, the screen takes turns between this and a second message, either Ignition Lockout or Ign 60 min Delay. With Ign 60 min Delay, the pilot went out 4 times and the heater waits 60 minutes before it tries again.
What the manual checks
Which second message shows depends on a control setup inside the heater. The message alone does not show why the pilot went out.
What you can safely note
Write down both messages and the full model number. Do not open the heater to check its setup.
Technician's part
A technician finds why the pilot went out.

Back to models

Rheem AVIA and AVIA with NiTek (A models)

These cards do not cover AVIA B models. Match your full model number to this manual.

Verifying Water

Normal
Applies to
Rheem AVIA P-M264A and P-M404A, not B models
What it means
A two-minute wait while the heater checks water flow.
What the manual checks
None needed.
What you can safely note
Did it move on after about two minutes?
Technician's part
Not needed for this message alone.

Vent Sw Open

Fault
Applies to
Rheem AVIA P-M264A and P-M404A, not B models
What it means
The vent air switch is open.
What the manual checks
The manual says to check the vent for a blockage.
What you can safely note
From where you stand, is anything on or against the vent? Do not reach in.
Technician's part
Ask a technician to do the vent check.

Automation Mode: Disabled

Setting
Applies to
Rheem AVIA P-M264A and P-M404A, not B models
What it means
A setting in the heater's menu, not a fault. While it is set to Disabled, schedules made online in the Raymote app are ignored. It is set to Enabled from the factory.
What the manual checks
None needed if someone chose this setting.
What you can safely note
Were app schedules supposed to run? Do not change service menu settings yourself.
Technician's part
Ask about the setting when you call.

Offline indicator in the Raymote app

App status
Applies to
Rheem AVIA P-M264A and P-M404A, not B models
What it means
The app cannot find the heater online. The manual says this can happen if the heater has no power, the Wi-Fi signal is weak or missing, or the Wi-Fi name or password changed.
What the manual checks
This badge says nothing about whether the heater has a fault.
What you can safely note
Look at the heater's own display from where you stand. Copy what it shows.
Technician's part
Not needed for this badge alone.

Back to models

Rheem Above Ground 106 and 156

The 106 has a dial control and no message screen. The 156 has a digital control. So screen messages apply only to the 156.

Main Ign Failure

Fault
Applies to
Rheem Above Ground 156, which has the screen
What it means
On a 156, the pilot flame went out while the heater was trying to light the main burner. The screen takes turns between this and a second message, either Ignition Lockout or Ign 6min Delay. With Ign 6min Delay, the pilot went out 4 times and the heater waits 6 minutes, not 60, before it tries again.
What the manual checks
Which second message shows depends on a control setup inside the heater. The message alone does not show why the pilot went out.
What you can safely note
Write down both messages and the full model number. Do not open the heater to check its setup.
Technician's part
A technician finds why the pilot went out.

Clock/Fireman Sw

Status
Applies to
Rheem Above Ground 156, which has the screen
What it means
On a 156, the time clock or fireman switch circuit is open. A time clock connects to the heater through this circuit. When a time clock is wired in, the manual says this shows when the clock has turned off the call for heat.
What the manual checks
The manual lists it with the active faults. Its time clock note explains why it can be expected.
What you can safely note
Is a timer or pool control set to stop heating at this time?
Technician's part
If it shows when the clock should be calling for heat, ask a technician. Do not check the wiring yourself.

Back to models

Not listed? Your message may still be real. Do not borrow a meaning from another model. Write down the exact words and the full model, and give both to Colin.

Planning a new Rheem heater: questions to settle

These questions come from Rheem's manuals. They show what the installer must check. They are not steps to do yourself. Gas, vent and wiring work belongs to a qualified installer, under local code.

Natural gas or propane?
Rheem's AVIA manual lists kits to change the gas type of the AVIA 264A and 404A, and says only a qualified agency should do it. That does not mean every Rheem heater can be changed, and it does not cover AVIA B models. The installer checks the full model, the gas line and the controls.Rheem AVIA manual (100-10000111 Rev 08), page 92
Digital or millivolt?
In the model number, E means electronic ignition with a digital control. M means a standing pilot with a dial. Millivolt models are not made to work with a remote control system.Rheem Digital and Millivolt manual (241236 Rev 43), pages 6 and 30
An Above Ground heater on propane?
Rheem says not to use small 5, 10 or 20 gallon propane tanks, like barbecue tanks, to supply this heater.Rheem Above Ground manual (241519 Rev 12), page 12
Do you want a message screen?
The Above Ground 106 has a dial. The 156 has a digital control that can show messages.Rheem Above Ground manual (241519 Rev 12), pages 16 and 17
Will a time clock run it?
When a time clock is wired in, a Digital heater shows Clock/Fireman Sw while the clock has turned off the call for heat. Plan the schedule with that in mind.Rheem Digital and Millivolt manual (241236 Rev 43), page 32

Safety first, then photos

If you smell gas, see smoke or fire, or think carbon monoxide is possible, do not stay to take photos. Move everyone away. Then call from a safe place. If you see smoke or fire, call 911. If carbon monoxide is possible, get to fresh air and call 911. If you smell gas and the heater uses natural gas, call 911 and your gas utility. If you smell gas and the heater uses propane, call your propane company, or 911 or the fire department.

When none of that applies, send a wide photo of the heater. Then send a close photo of the outside label and any display you can already see. Give the fuel and serial number only if a label shows them. Leave panels in place.

What a repair visit costs

A repair visit is a service call. You hear the fee before the visit. It pays for Colin's first hour of on-site checking and testing. It is due even if you turn down the repair. After that you get a total-price quote, good for 15 days from the date it is issued. No repair or installation work starts until you approve that price. Full fee and quote rules

Call Colin at 941-961-9337, Monday to Friday, 8 AM to 5 PM.

Sources and limits

The message lookup and install planning notes above come from these manufacturer manuals. Each card and answer names its manual and page. The manual copies used here were retrieved on the date shown. A manufacturer can change a manual later, so check the manual for your own heater too.

Not covered on this page

  • AVIA B and AVIA with NiTek B models.
  • Rheem commercial ASME heaters.
  • Messages on Millivolt and Above Ground 106 heaters, which have no message screen.

More pool-heater help

Explore pool-heater service

Talk with Colin

Tell Colin what the heater is doing.

Call Colin941-961-9337