The new touch screen Delta - The jewel in the Calorex Crown

The new PLC controlled Calorex Delta has aroused much interest in the industry. As Calorex’s exclusive supplier to the pool trade, we at Certikin believe they are a breath of fresh air but don’t take our word for it. Fresh from commissioning a Delta 6 at Scarborough’s Crown Spa Hotel,  Anthony Houfe of Pool Heat Ltd in Hull gives his account of its installation and an honest appraisal.

As proud Calorex approved service agents for the past 25 years, we maintain a very good relationship with Calorex and Certikin, speaking with them daily. When we were made aware of the new PLC controlled Deltas coming to the market we watched closely for its release.

“In the meantime we had a very good customer, the Crown Spa Hotel in Scarborough, who we look after and maintained with a Calorex Delta 6B which was now approaching 14 years old. One day in passing I spoke with the hotel’s Spa manager, Stuart Russell, about the new PLC Calorex model. He asked us to provide some more information so they could weigh up the benefits of the new model over the existing one and asked for a price. The hotel is very ‘green’ and environmentally friendly and wherever possible looks to reduce energy usage. They did the sums and an order was duly placed with us.

“We spoke to Calorex to see if it was possible to build the machine on site as the old Delta would have to come out in small pieces as the plant room had been built after the original install by another company. Calorex suggested a dry jointed machine, which meant that it was in effect “built” in the Calorex factory. Certikin delivered the unit to site on the day requested.

“The old machine was stripped down and brought out of the plant room in manageable pieces. We then stripped the brand new machine down taking out everything from the inside - the coils, compressor, fans and wiring. In fact, we stripped it to a point that you wouldn't recognise it as a Delta (see attached image). We carried everything back into the plant room and then started to rebuild it panel by panel. 

“We then “built” it on site, brazed up the refrigeration circuit and charged it with refrigerant, plumbed the water circuit and wired it all up.The rebuild took a few days including numerous rivets, installing the wiring loom, rewiring the complete machine and all the pipe work inside the Delta. We pressure tested the refrigeration circuit, evacuation and finally recharged to Calorex standards and specifications.

“We couldn't have been more impressed with the machine. We got great support as always from the Calorex service department and when we switched the machine on it worked first time, just as we expected.”

“I must say that it has not only met but surpassed our expectations. We monitored the equipment after installation very closely and the feedback we got from the Crown Spa Hotel was very good indeed. They can tell the difference in the environment, pool hall and water temperature. The Delta heats the air and water so efficiently and the humidity is very tightly controlled. This we can verify, because when we access the PLC logs, which are recorded in the memory of the Delta, we can see just how it has performed since installation. Another major advantage is that we have managed to cut down the electrical consumption of the site because the Delta uses inverters to control the fans. Indeed, we have more than halved the fan running amps compared to the old machine. The customer has also noticed how efficiently the water heats up even after a backwash. It is also possible for the customer to remotely monitor the Delta if required.

“Being one of the first Delta PLC machines ever installed was not a concern for us as we have great confidence in the Delta’s performance, and the fact that we had to build it from the ground up didn’t phase us either. We had fantastic support from Calorex and Certikin. The build quality means that there was no other machine that we even considered, as no other machine on the market would have done the job we intended with such great results.

Stuart Russell, Crown Spa Health Club and Spa Manager says:

“Since the installation of the new Delta we have seen a marked improvement to the pool hall environment and pool water.  It is more economical and convenient to use.  The support and professionalism we have received from Anthony at PoolHeat and Calorex has been excellent.”


Calorex is in touch 

With new touch screen technology and a remote internet connection, Calorex’s upgraded Delta range allows you to control your pool room directly from your smartphone or computer.

All the models in Calorex’s Delta range of swimming pool environmental controls now come with a 7” touch screen display providing the ultimate flexibility in system management. The unit can be controlled and adjusted on-site to match fan speeds precisely to ductwork resistance and automatically vary exhaust speeds to match building load requirements.

Designed and manufactured in the UK under ISO9001 compliance, the highly innovative Delta range also features new EC/inverter fans as standard. These new fans are approximately 20 per cent more efficient due to the ability to adjust and control fan speed based upon demand through the PLC controller  which allows the overall system efficiency to improve by up to 40 per cent. Delta 1 to 12 now feature low pressure drop plate heat exchangers with 50 per cent more capacity than current units.

Contact Certikin H&V on 01993 777200 or email Our H&V experts will be happy to discuss your requirements and specify a system to meet the H&V needs of your project.

Pool Heat Ltd Tel: 01482 701910


Crowne Spa Hotel 

Delta in Crown Spa plant room

Delta control panel

In control with the Calorex Delta