Indoor Pool Heating Guide

Indoor Pool Heating Guide

This indoor pool heating guide explains the different options for pool water heating, dehumidification, air heating and fresh air handling for indoor pools

indoor pool heat pumps and dehumidifiers

Indoor pools have more complex design requirements than outdoor pools due to the need to also control humidity and to heat the pool room air.

We offer a full design service for domestic and commercial indoor swimming pools.

Indoor Pool Heating Design Service

As part of our design service for indoor pools, we will discuss with you the planned use of the pool and will design a solution for you to provide:-

  • Pool Water Heating
  • Air Heating
  • Air Dehumification
  • Fresh Air Ventilation
  • Ducting

There are two main options for indoor pools:-

  1. “All-In-One” type systems to provide pool water heating, dehumidificaion and air heating. They can use ducting to blow the warm dehumidified air over any glass surfaces in the pool room.
  2. Separate units – ie heat pump for the pool water heating and stand-alone dehumidifier that can also heat the pool room air

The choice of these is often dictated by the amount of glass present in the pool hall.

Ideally the amount of glass should be kept to a minimum, but if a lot of external glass is present, then to avoid condensation, a ducted solution should be used to allow warm dehumidified air to be blown over the glass surfaces.

If the amount of glass is small, then a separate wall mounted dehumidifier and heat pump for the pool water can be used.

For our Indoor Pool Design Service, we charge £50 (Inc VAT). This is then refundable against any equipment that is purchased from us.

“All-in-One” Solutions for Indoor Pools

“All in one” solutions for indoor pools can provide pool water heating, dehumidification, fresh air introduction and air heating from one unit. They achieve high energy efficiency by recovering heat during the dehumidification process and can return this heat to the pool water or to heat the air in the pool room.

The all-in-one solutions can use ducting to transfer the warm dehumidified air over any glass surfaces in the pool room.

They can also be supplied as a simple “suck-blow” type unit where the unit sits in the plant room and a grille through the wall to the pool room sucks in air, warms and dehumidifies it and blows it back into the pool hall via another grille. This is typically the Heatstar Orion or the Calorex Variheat units.

The all-in-one solutions need a heat source to power them. This can be a gas/oil boiler or we can design and supply them to use an air source heat pump as the heat source. Using a heat pump can give a lower running cost than using a boiler.

We sell a range of all in one solutions from Calorex, Heatstar and Recotherm

These solutions are designed specifically for each pool hall, so please contact us for a proposal to suit your particular requirements.

Separate Units for Indoor Pools

If a ducted or all-in-one type unit is not required, then separate units can be supplied for the pool water heating, air heating and dehumidification.

We can supply a heat pump for the pool water that can operate all-year round at low temperatures

We sell a range of dehumidifiers both floor or wall-mounted models. These have the option to also heat the pool room air using either a hot water supply from a boiler (LPHW), or using a built in electric heating element.

Heat Pumps for Indoor Pools

We have specific heat pumps that are suited to indoor pools, for example the Duratech Dura+ and Calorex extended season heat pumps.

Duratech Dura+ Heat Pumps


We sell a wide range of dehumidifiers from Calorex and Heatstar

Calorex Monitair Dehumidifiers

indoor pool dehumidifier - heatpumps4pools

Ducted Dehumidifiers

As well as the larger Calorex Variheat and Heastar Andromeda all in one units, we also have the smaller Calorex AA300 and AA500 units.


The AA300 and AA500 are cheaper than the larger all in one units and can provide dehumidification, air heating and pool water heating.

To see more information on the AA300/AA500, please click HERE

Click Here to see our full range of dehumidifiers

Fresh Air Introduction

For an indoor pool, it is also important to introduce fresh air to the pool hall to reduce the chance of mould growth.

We sell a specially designed fresh air unit called the Indux E300.

This is an “intelligent” extract fan that extracts air from the pool hall to the outside, but as it does so, it warms the fresh air coming into the pool hall to provide heat transfer and energy efficiency.

indux e300 pool ventilator

Click Here for more details on the Indux E300

Ducting Design and Installation Service

We offer a full ducting design and installation service which is available throughout the UK

The photos below show examples of work completed by HeatPumps4Pools

Please contact us for a quotation.

Ducted System Fed from a Domestic Air Source Heat Pump

We can also design a system which is powered by an domstic air source heat pump, feeding a buffer tank

heat-pump-with-buffer-tank-configuration - heatpumps4pools

Indoor Pool Heating Design Considerations

In order to design a solution for your indoor pool, we take into account the following:-

  • Dimensions of the pool
  • Dimensions of the pool room
  • Any existing heat sources, eg boilers
  • Any existing air heating systems, eg underfloor heating, radiators etc
  • Construction of the pool room, ie U-values of the walls and roof
  • Insulation in the pool room
  • The amount of glass surfaces present
  • The expected use of the pool, eg commercial or domestic
  • The season that the pool will be used, eg all year round.
  • Required air and water temperatures
  • If the pool will be covered when not in use
  • Ducted all-in-one or separate non-ducted solutions
  • Electricity supply, single or 3-phase, any limitations on the supply.
  • Dehumidifiers – wall mounted, floor standing, or located in the plant room (through the wall type).
  • Construction drawings for the pool room
  • Building regulations
  • etc..

Indoor Pool Construction Guide

You may find the following guide useful which outlines best practice when building an indoor pool hall

Please Contact us to discuss a solution for your indoor pool to suit your budget.

Please Contact us to discuss a solution for your indoor pool to suit your budget.