Principles Of Controlling An Underfl Oor Heating System (Ufh) - Rehau STAR 20 Installation Manuallines

PRINCIPLES OF CONTROLLING AN
UNDERFLOOR HEATING SYSTEM (UFH)
REHAU Underfl oor Heating
REHAU Underfl oor Heating is a favoured choice for industry professionals.
Practical, cost-effective and fl exible, Underfl oor heating is increasingly
being specifi ed over traditional radiator systems and establishing a
reputation as the preferred modern-day heating solution.
Most common are the wet systems (using warm water), though there
are also electric (dry) systems available. Pipes are normally buried in
the screed, or run underneath the fl oor surface. The pipes transfer
heat from the (slightly warmer) fl oor into the wider room space, which
is more effi cient than traditional plumber-installed radiators which
transfer heat from a relatively small and very hot surface into a much
larger and cooler space (the room).
Advantages
- Comfort – Even spread of heat provides a high level of comfort.
- Economy – reduced demand on boilers and no wasted heat at
ceiling height saves costs.
- Cost-effi ciency – Reduced on-site maintenance – servicing of
boilers and pumps only.
- Flexibility – Unrestricted wall surfaces in both old and new buildings.
- Safety – No hazardous wall projections or hot surfaces.
- Control – REHAU comprehensive controls package offers a solution
for the majority of building applications.
Underfl oor Heating Power Source
The heating can be powered by many types of boilers, ground source
heat pumps or even solar thermal panels, and your corgi plumber can
advise on the best boiler solution for your system. Gas, oil or solid
fuels can be used to power up the system, and the best advise is to
consult your professional plumber for the appropriate solution for your
requirements. Your plumber can further direct you to a condensing
boiler that is most suited to your system, as condensing boilers are
highly effi cient and match well the requirement of the underfl oor
heating system, thus operating at their most effi cient point.
Underfl oor Heating Considerations
Your plumber can install the REHAU Underfl oor heating system
at either new property developments or as refurbishment and
redevelopment or an existing property. Your plumber will be able to
design a combined system that uses both traditional radiators and
underfl oor heating. For example your corgi registered plumber can
design a system that uses underfl oor heating system for the ground
fl oor of your home and radiators for the upper fl oor. Alternatively,
the plumber can advise to use wet radiators in specifi c rooms (e.g.
bathroom, toilet). The best advice is to use a qualifi ed corgi plumber
that can design a heating system that is unique and bespoke to your
needs.
Further Information on Underfl oor systems can be obtained from
REHAU such as:
- Explain the basic principles of warm water underfl oor heating (UFH)
systems
- State the advantages of UFH systems
- Identify the design conditions and relevant standards appropriate
with UFH systems
- Carry out heat loss calculations
- Describe the fl oor systems and fi nishes associated with UHF
systems
- State the various UFH systems types of the market
- Explain the operation of UFH systems and components
Carry out UFH system design using worksheets, including working on
a project building
Zone Control
The REHAU STAR control system is a sophisticated electronic control
system that has been specifi cally designed to give optimum and
accurate control of FH systems. FH circuits are connected to a central
manifold. Each circuit will have a thermoelectric actuator (AC) on the
manifold operating the return valve for the circuit.
The heat output in each room is controlled by a room controller, which
continuously compares the required room temperature with the actual
room temperature. If the room temperature is too low, it will signal the
actuator (AC) to open the return valve of the circuit and allow warm
water to fl ow through it. (as shown in fi gure 3)
Zone controls give control over local/room temperature by adjusting
the amount of water circulating within individual circuits/zones.
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