What A Gas Pool Heater Installation Actually Requires

Here's a situation we'd rather help you avoid: a heater arrives on a pallet, and then you find out your gas meter can't supply it, or the only place it fits is three feet from a window, or your house needs a new gas run across the yard that costs more than the heater did.

None of that is exotic. It's just the stuff nobody tells you to check first.

This post is the checklist. It won't teach you to install a gas heater — that's licensed work for good reason, and we're not going to pretend otherwise. What it will do is let you qualify your own house in an afternoon and have an informed conversation with a contractor before you spend anything.

First, the honest framing

A gas pool heater is a gas appliance with a substantial input rating. A 266,000 BTU heater is bigger than most residential furnaces. That has consequences for your gas supply, for venting, and for where it can legally sit.

Gas fitting, venting and combustion air are work for a licensed professional, and in most jurisdictions they're work that requires a permit and inspection. This isn't red tape for its own sake — improper gas work and improper venting cause fires and carbon monoxide incidents. Please hire someone.

What follows is what to check and what to ask.

1. Can your gas supply actually feed it?

This is the number one reason a heater purchase falls apart, and it's the first thing to check.

Two separate questions:

Does your meter have capacity? Your gas meter has a rated capacity, and everything in the house draws from it — furnace, water heater, range, dryer, fireplace. Adding a 266,000 BTU appliance is a significant new load. If the total demand exceeds what the meter can deliver, the utility needs to upgrade it. That's usually a call to the gas company, and it's often free or low-cost, but it takes time.

Is the supply line big enough? This is the expensive one. Gas piping has to be sized for both the BTU demand and the distance from the meter, and pool heaters are frequently the furthest appliance from the meter in the whole system. A line that's adequate at 40 feet may be undersized at 90 feet.

An undersized line doesn't fail dramatically — it starves the heater, which causes poor combustion, nuisance shutdowns, sooting and premature failure. Then people blame the heater.

What to do: before you order, call a licensed plumber or HVAC contractor. Tell them the BTU rating of the heater you're considering, where your meter is, and where the pool equipment sits. Ask for a rough quote on the gas run. That single phone call is the most valuable thing in this article.

2. Propane changes the math

If you don't have natural gas, propane is the alternative — the heaters are the same units with different orificing, and you buy the propane version rather than converting.

Things to confirm:

Tank size. A 266,000 BTU heater burns roughly 2.9 gallons per hour at full fire. A small tank will not keep up, and a nearly empty large tank can struggle to vaporize fast enough in cold weather.
Vaporization rate. Propane has to boil off inside the tank to feed the appliance, and cold weather plus a low tank reduces that rate. This is exactly the shoulder-season condition you bought the heater for.
Delivery and cost. Propane usually costs more per BTU than natural gas. Work through the running cost math on propane pricing before committing.
Regulator sizing. Your regulator and line need to handle the added load.

3. Location, clearances and venting

Gas pool heaters are outdoor appliances, and where they can sit is governed by the manufacturer's instructions and by code. Broadly, the things that matter:

Clearance from the building. There are required distances from combustible surfaces.

Distance from openings. Windows, doors, vents and air intakes all have minimum separations, because combustion exhaust must not be drawn into the house.

Overhead obstructions. These heaters vent upward. Decks, eaves, overhangs and roofs above the unit are a problem.

Never indoors or in an enclosure without proper venting. Not in a shed, not under a deck, not in a boxed-in equipment closet. Outdoor units need free combustion air and unobstructed exhaust.

Clear space for service. Someone will need to open it and work on it.

A level, solid pad. A concrete pad or patio stones, not dirt or grass. Our kits list a 24" × 30" patio stone for the pump and filter; the heater needs its own solid base.

The Raypak Digital heaters we carry are designed with a wind-resistant top and a ceramic fiber combustion box that keeps the outer jacket cool, which helps with real-world outdoor installation — but none of that changes the clearance requirements. Read the manual for your specific model, and have your installer confirm against local code.

4. Electrical

Gas heaters still need power. The Raypak Digital units use electronic ignition and a microprocessor control board rather than a standing pilot, which is more efficient and more reliable — and it means a proper electrical connection.

You'll need an appropriately protected circuit, and the whole pool equipment area needs correct bonding and grounding. Pool bonding is a code requirement with real safety consequences, and it applies to the heater as much as the pump. Get a licensed electrician involved. This is the same conversation as the one in our cost guide — worth having once, for the whole equipment pad.

5. Plumbing

The heater goes into your circulation loop, and order matters: pump, then filter, then heater, then back to the pool. Filtered water through the heater, always — debris in a heat exchanger is a problem.

The Raypak Digital units come with 2" slip-fit CPVC connections and an integrated bypass that balances flow automatically, and they'll pass high flow rates without excessive pressure drop. Your installer will want to confirm your plumbing size and pump output are appropriate.

If you're already running rigid PVC, you're in good shape — see our hard plumbing guide.

6. Permits and inspection

Most jurisdictions require a permit for gas appliance installation, and many require electrical permits too. Some also require inspection before the gas is turned on.

Call your building department before the work starts. Permits are cheap; unpermitted gas work discovered at closing when you sell the house is not. It can also matter for insurance.

7. Elevation

This one catches people out, and it's specific to gas.

Gas heaters are configured for altitude. Thinner air at elevation changes the air-to-fuel ratio, and running a sea-level unit at 5,000 feet causes incomplete combustion, sooting and pilot problems. That's why these heaters ship in different elevation configurations — a standard model for lower elevations, and separate high-altitude versions.

If you live at altitude, you must order the right configuration. This isn't an adjustment your installer makes on site. We cover it in detail in which Raypak heater do I need, and if you're anywhere above about 2,000 feet, please call us before ordering.

Your pre-purchase checklist

Work through this before you order anything:

If more than one or two of those come back as unknowns, call us before you buy. We would much rather talk you through it now.

The short version

Gas heaters are serious gas appliances. A 266,000 BTU unit is larger than most home furnaces.
The most common dealbreaker is gas supply: meter capacity and line sizing over distance.
Get a licensed contractor's quote on the gas run before ordering the heater.
Propane works but burns roughly 2.9 gallons per hour on a 266K unit — check tank size and cold-weather vaporization.
Outdoors only, with clearances from the building, from openings, and nothing overhead.
Electronic ignition means it needs power, and the equipment pad needs proper bonding.
Plumb it pump → filter → heater → pool.
Permits are usually required. Get them.
Order the correct elevation configuration if you're at altitude.