Gas based heating · Auckland
Underfloor and pool from one boiler
Underfloor + pool
The floors want heat in winter and the pool wants it in summer
One boiler, two circuits, one exchanger
Swipe the diagram sideways to follow the full circuit →
One boiler, one primary circuit
The boiler makes warm water and nothing else. Where that heat goes is a question of pipework and controls — flue gases out, condensate to the drain.
Diverter valve
A three-port valve sends the primary flow to the manifold or to the pool exchanger. Floors in winter, pool in summer, changeover automatic.
The circuits never mix
Pool water runs pump, filter, then one side of a plate heat exchanger. Heat crosses the plates; treated water stays out of the house entirely.
Sized for the bigger load
A pool needs far more heat than a slab. We size and pipe for both at quote stage.
The boilers we fit
Click a boiler to see its full specifications.
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 DuoHeat heat pump suits you if…
- You want both jobs from one machine with a low running cost
- The pool is held at temperature through the season rather than heated in bursts
- You are building new and can size the plant properly from the drawings
- See the heat pump version
Gas suits you if…
- Gas is already at the house and the boiler is being replaced anyway
- The pool is used occasionally and wants fast heat rather than steady heat
- There is no outdoor space for a unit big enough to do both
- Up-front cost is the constraint
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
Underfloor and pool on gas: questions
Can one boiler do both?
Yes, with a plate heat exchanger and a properly designed control strategy. What it cannot do is heat a large pool from cold and hold the house at temperature at the same time on a small boiler. That is a sizing question, and it is the first thing we work out.
Why does the pool need a heat exchanger?
Pool water is chlorinated or salt-treated and would damage the boiler and the pipework in your slab. The exchanger transfers heat between the two circuits without the water mixing.
Can I stage it — house now, pool later?
Yes. We size and position the plant for both, pipe and cap the pool leg, and connect it when the pool goes in. Allowing for it at the start costs much less than retrofitting later.
What about hot water as well?
All three from one boiler is possible and we have installed it. It needs specific design rather than a standard layout, so talk to us before choosing a boiler size.
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.