Raypak AVIA 264 vs 404 Which Pool Heater Size Do You Need

Raypak AVIA 264 vs 404: Which Pool Heater Size Do You Need?

Raypak AVIA Sizing Guide

Raypak AVIA 264 vs 404

Both heaters share the AVIA platform, Raymote connectivity and 84% thermal efficiency. The real decision is how much heating capacity your pool, spa, climate and gas supply actually require.

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264K AVIA 264 BTU input
VS
399K AVIA 404 BTU input
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Quick answer

Choose the Raypak AVIA 264 when the pool is moderate in size, heat-up speed is not the highest priority and the available gas supply is better suited to a 264,000 BTU heater. Choose the AVIA 404 when you have a larger pool, an attached spa, frequent cold-start heating, cooler weather or a strong preference for faster recovery. The larger heater only makes sense when the gas meter, regulator, piping, water flow and installation can support it.

Customers often ask for a simple gallon cutoff between the AVIA 264 and 404. Gallons matter, but they are not enough to size a heater correctly.

Two pools can hold the same amount of water and have very different heating demands. A shallow pool with a large exposed surface can lose more heat than a deeper pool with less surface area. Wind, overnight temperature, humidity, cover use and the desired water temperature all affect how hard the heater must work.

AVIA 264 and 404 Side by Side

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Specification AVIA 264 AVIA 404
Published input 264,000 BTU/hr 399,000 BTU/hr
Thermal efficiency 84% 84%
Approximate useful output About 221,760 BTU/hr About 335,160 BTU/hr
Water connections 2-inch buttress 2-inch buttress
Published flow range 40 to 100 GPM 40 to 100 GPM
Gas options Natural gas or propane Natural gas or propane
Heat-exchanger options Copper or NiTek Copper or NiTek
Typical reason to choose Moderate demand and lower initial cost Faster recovery and greater heating demand
Moderate heating demand AVIA 264
  • 264,000 BTU input
  • Good fit for many moderate residential pools
  • Lower hourly fuel demand than the 404
  • May fit gas infrastructure that cannot support the larger heater
  • Longer heat-up time than the 404 under comparable conditions
```

Six Factors That Determine the Correct AVIA Size

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1

Pool Volume

More water requires more energy for every degree of temperature increase.

2

Surface Area

The exposed water surface is where a large share of pool heat loss occurs.

3

Temperature Rise

Heating from 60°F to 82°F is a much larger job than maintaining 78°F to 82°F.

4

Wind and Weather

Wind, cool air and dry conditions can rapidly increase evaporation and heat loss.

5

Pool Cover

A properly used cover can reduce evaporative and overnight heat loss substantially.

6

Spa Use

An attached spa often shifts the decision toward the larger heater because fast recovery matters.

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How Much Faster Is the AVIA 404?

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Because both models are rated at 84% thermal efficiency, the AVIA 404 delivers approximately 51% more useful heat output per hour than the AVIA 264 under comparable ideal conditions.

Simple theoretical heating formula

Gallons × 8.34 × Temperature Rise ÷ Useful BTU Output

This formula provides an idealized estimate. It does not account for wind, evaporation, uncovered water, cool plumbing, environmental losses or changing outdoor conditions.

10,000 gallons + 10°F AVIA 264: approximately 3.8 ideal hours
AVIA 404: approximately 2.5 ideal hours
15,000 gallons + 10°F AVIA 264: approximately 5.6 ideal hours
AVIA 404: approximately 3.7 ideal hours
20,000 gallons + 10°F AVIA 264: approximately 7.5 ideal hours
AVIA 404: approximately 5.0 ideal hours
These are planning estimates, not guaranteed heat-up times. Actual heating normally takes longer because the pool continues losing heat while the heater operates. Air temperature, wind, humidity, plumbing, cover use and pool exposure all affect the result.
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The Gas Line Can Decide the Heater Size

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A homeowner may want the AVIA 404 but have a gas system that cannot reliably supply a 399,000 BTU appliance at the required dynamic pressure.

Gas-pipe capacity depends on fuel type, pipe material, pipe diameter, equivalent length, fittings, regulator arrangement, meter capacity and the demand from other appliances. A qualified gas professional must evaluate the actual installation.

Do not select the 404 first and investigate the gas line later. An undersized or improperly configured gas supply can cause ignition problems, poor combustion, nuisance shutdowns or unsafe operation. Confirm available capacity before ordering.
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Does the AVIA 404 Cost More to Operate?

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The AVIA 404 burns fuel at a higher hourly rate while firing, but it also heats the pool faster. That does not mean the total cost of achieving the same temperature rise increases in direct proportion to the heater’s input.

In an ideal system, heaters with the same thermal efficiency require a similar total quantity of fuel to add the same amount of heat to the same volume of water. The larger heater delivers that heat in less time.

Real-world cost still varies because of weather, cycling, standby losses, plumbing, fuel rates and how the homeowner uses the pool. The practical question is whether the faster recovery of the 404 is worth the higher equipment price and potentially greater gas-infrastructure requirements.

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Real-World AVIA Sizing Scenarios

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Scenario 1: Moderate pool maintained throughout the season

A homeowner has a moderate in-ground pool, uses a cover, keeps the water near the desired temperature and does not have an attached spa.

Likely direction: The AVIA 264 may be sufficient when a proper heat-loss evaluation and the available gas supply support it.

Scenario 2: Larger Northeast pool heated mainly on weekends

The pool cools during the week and needs a substantial temperature increase before Friday evening. Spring and fall operation are important.

Likely direction: The AVIA 404 may be the stronger choice because recovery speed is a major part of the homeowner’s goal.

Scenario 3: Pool with an attached spa

The pool itself is not extremely large, but the homeowner expects the spa to heat quickly for evening use.

Likely direction: The AVIA 404 is often attractive because spa recovery changes the sizing priorities.

Scenario 4: Larger heater requested but gas service is limited

The homeowner wants the fastest model, but the existing meter and long gas run may not support 399,000 BTU without upgrades.

Likely direction: Resolve gas capacity before selecting. The 264 may be more practical, or the site may require professional gas-system modifications.

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A Better Way to Choose Between the 264 and 404

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1. Measure the Pool Record length, width, average depth, gallons and approximate surface area.
2. Define the Goal Decide whether you maintain temperature or frequently reheat a cold pool.
3. Evaluate Heat Loss Consider wind, cover use, spa demand and the length of the swimming season.
4. Verify Utilities Confirm fuel type, meter, regulator, gas piping, water flow and electrical supply.
```

Raypak AVIA 264 vs 404 Frequently Asked Questions

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What size pool can an AVIA 264 heat?
There is no universal gallon rating that applies to every installation. The AVIA 264 can serve many moderate residential pools, but climate, surface area, temperature rise, cover use and recovery expectations must also be considered.
Is the AVIA 404 too large for a small pool?
Not necessarily, especially when an attached spa or fast recovery is important. However, the gas supply, hydraulic system and expected cycling behavior should be evaluated rather than selecting solely for maximum BTU.
Does the AVIA 404 use more gas?
It consumes gas at a higher hourly rate while firing because its input is 399,000 BTU per hour versus 264,000 BTU per hour. It also completes a given heating task faster under comparable conditions.
Are the AVIA 264 and 404 the same physical size?
Raypak publishes both models within the same compact cabinet family, but the current dimensions, connections and service clearances should always be verified before replacement or installation.
Should Northeast pool owners automatically choose the 404?
No. Cooler weather, short swimming seasons and rapid weekend recovery can make the additional capacity valuable, but pool size, cover use, spa demand and gas capacity still determine the correct model.
Does a pool cover affect heater sizing?
Yes. A cover reduces evaporative heat loss and can substantially improve heat retention. It may not change the heater selected in every installation, but it can reduce run time and improve real-world performance.
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Still Deciding Between the AVIA 264 and 404?

Send Aqua Terra Backyard your pool dimensions, approximate gallons, gas type, ZIP code, desired water temperature, attached-spa information and equipment-pad photos. We can help identify the more appropriate AVIA configuration before you purchase.

``` Shop Gas Pool Heaters Request Sizing Help ```

Heating-time examples are theoretical estimates based on published input and thermal efficiency. Actual performance varies. Heater sizing and gas-system evaluation should be completed by qualified professionals using current manufacturer documentation and local requirements.

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