Gas based heating · Auckland
Gas pool heating
Pool heating
Gas heats pool water faster than a heat pump. A cold pool can be brought up to temperature in hours rather than a day or two. The running cost is higher than a heat pump, so gas suits pools and spas that are heated occasionally.
How a gas pool heater works
Swipe the diagram sideways to follow the full circuit →
Fitted on the return leg
The heater sits after the pump and filter, with isolating valves either side so it can be serviced without draining anything.
Gas in, flue out
A gas supply runs to the heater and it needs a flue termination clear of windows and doors, so where it goes is planned before we start.
Gas or heat pump
Gas and heat pump are not rivals in our shop — we install and service both, every week. What follows is how we actually decide.
A pool heat pump suits you if…
- You swim regularly through the season rather than occasionally
- You want the pool held at temperature rather than heated from cold
- Running cost over the season matters more than heat-up time
- You have a cover — it roughly halves the load either way
Gas suits you if…
- You want the water warm today, not on Thursday
- It is a spa, or a pool used in bursts
- There is no space or power for a heat pump by the pool
- You already have a gas heater and only the unit has failed
If gas is already at the house and the boiler position is easy, a condensing boiler is normally cheaper to put in and more expensive to run. A heat pump is the other way round. Which wins depends on how long you are staying, what the gas connection costs, and whether you also want pool or hot water off the same plant. Ask us and we will price both.
Questions
Gas pool heating, answered
How much more does gas cost to run than a heat pump?
Substantially more — a pool heat pump delivers roughly five units of heat per unit of power, while a gas heater delivers slightly less than one unit of heat per unit of gas paid for. Over a full swimming season that gap is large. Over four weekends a year it is not.
Can I have both?
Yes, and on larger pools it is a sensible setup: the heat pump does the steady work and holds temperature, and the gas heater is there for when you want the water up quickly. They plumb into the same circuit.
Will a cover make a difference?
More than any equipment decision you will make. An uncovered pool loses most of its heat from the surface overnight. A cover typically halves the running cost whatever is heating it.
Can the same boiler do my house and my pool?
Sometimes, but it is not usually the right answer — a pool is a very different load from a slab, and the pool wants heat in summer when the house does not. See underfloor and pool combined.
Free, no obligation
Request a quote
Send the plans, or tell us what is there now. We will price the gas option and the heat pump option side by side.