We had the system for 7 years. It keeps the house marvellously warm. Specially with the automatic Delta controller.’ Mr. Peter Ketelaar. Inverness, Scotland.
IPPEC offers a comprehensive range of advanced temperature controls

PEXATHERM Advanced Temperature Control - Underfloor and Radiator Heating

The Delta weather compensator and programmer

Delta Contoller
Many underfloor heating systems are characterised by poor temperature control. Many of the so-called 'simple' controls are woefully inadequate as the response time of underfloor heating and the high insulation of modern homes are incompatible. In other words, by the time the internal thermostat senses the change of temperature, the environment has become too cold or too hot and the underfloor system will take even longer to respond to this change. The Delta weather compensators, with many advanced features, detects changes with an outside sensor and adjusts the temperature in the floor and the boiler output to provide the ultimate in comfort and energy saving. Internal room sensor option can be supplied. Delta for 2 boilers is also available.


Click to see animation Delta weather compensation animation

Accessories
The Pexatherm W100 / 200 enclosures shown with the Delta simplfies installation by providing a connection panel and manual controls for the controls electrician. The labeled terminals are underneath the Delta in the WG enclosure panel.
Options
Internal sensors and high limit floor sensors are available as extra options. Several types of Pexatherm servo motors control the different mixers besides the standard SM 4 unit.

Wiring
All the Delta controller wiring is via the WG enclosure. Click the button to see the Delta wiring schematics.

Servo motor SM4

What is weather compensation?

Weather compensation
As the external temperature varies between day and night, the internal thermostat cannot detect these variations fast enough. This results in not enough heat in the morning and overheat in mid afternoon. The outside sensor of the Delta allows instant response to temperature changes. The boiler output is increased and the mixer lets warmer water in the floor. This the inside temperature follows the pre-set comfort temp. all the time.		 Temperature curves
The water temperature in the boiler and in the floor is determined by the corresponding slopes and the outside temperature. These slopes can be adjusted and shifted from left to right to give the required comfort level.
Boiler characteristics
Non modulating boilers adjust their water temperature by starting and stopping at intervals. This is called boiler cycling. The job of advanced controls is to reduce the cycling while running thr boiler at the lowest possible temperature. The boiler sensors in conjunction with outside sensor are used by the Gamma to acheive this optimum situation. The boiler output is optimised withou tallowing the boiler temp. to drop below the pre-set minimum at all times.		 Parallel shift
The water temperature in the boiler and in the floor is determined by the outside temperature based gradient of the slope for the specific heating system. These slopes can be adjusted for gradient and can be shifted in parallel to the left or to the right to increase or decrease the temperature to give the precise comfort level.

How does it work?

The Delta schematic
The four sensors of the Delta connect to the left of the WG100/200 enclosure panel, while the output to boiler, pumps, valves and mixer servo-motor to the other side of the panel.
Many featured can be incorporated with the independant output from the Delta. The boiler and pump can be run in such a way to dissipate all the heat from boiler (pump overrun).
The full boiler output can be diverted to cylinder when required to achieve rapid heat up of the domestic hot water (DHW priority).
The domestic hot water temperature in the cylinder and many other temperature settings can be set at the Delta.
Motorised valves wiring is simplified as all the relays are built in the Delta.
The Delta can be used with UFH and radiator central heating. There are several Delta controllers to suit most installations.

IPPEC can provide each installation with its particular Delta schematic connection and controls design. Please contact us for more details.
Press button to view operation summary.

 
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