Polypipe Under Floor Heating Systems Technical Installation Manual Download

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ROOM TEMPERATURE CONTROL

Controlling under floor heating

The control of under floor heating systems is different to that
of conventional radiator systems, as the space should not
be allowed to cool completely during the heating season.
The temperature during unoccupied or night time periods
should fall to around 4°C lower than the occupied temperature.
This lower temperature setting is known as the set-back
temperature, e.g. occupied temperature 21°C, set-back
temperature 17°C.

Individual room control

Polypipe under floor heating controls allow each room to
be both time and temperature controlled via the use of a
programmable room thermostat. Each thermostat is wired
back to a master wiring centre and slave unit, which in turns
operates the relevant manifold actuator/s, the under floor
heating pump, and the two-port zone valve. The master wiring
centre is also capable of providing either a 230V or a Volt free
switched live supply to signal the boiler.

Schematic switching diagram - relays not shown

As individual rooms reach their set point temperature or when
the system is operating in ‘set back’ mode the master wiring
centre will de-energise the pump and zone valve and the signal
to the boiler will be cut, ensuring that maximum comfort levels
and system efficiencies are achieved and maintained at all times.

The number of control zones you require will depend on the
number of rooms you wish to control individually. The 4, 6 and
8 zone packs describe the number of areas you wish to control,
not necessarily the number of circuits you are supplying from
that manifold. To optimise the use of each control pack you will
need to understand the following guidelines:
• The 4 zone pack contains 4 room thermostats; the 6 zone

pack contains 6 room thermostats; and the 8 zone pack
contains 8 room thermostats

• Each room thermostat can control 1 zone and

up to 4 actuators

• Rooms over 40m

should be allocated as 2 zones

and have 2 room thermostats

• An actuator is required on each circuit that requires control

The room thermostats (PBPRP) and wiring centres are available
as individual items or packs, as detailed below:

A comprehensive range of room temperature control products are available

to complement Polypipe under floor heating systems. Designed specifically to

maximise both comfort and efficiency, the unique programming functions provide

the perfect control solution for under floor heating systems.

WATER TEMPERATURE CONTROLS

The temperature of water required in under floor heating systems is less than

that required for radiators or stored hot water. If these other services are

connected to the same boiler it will be necessary to control the water

temperature using one of the Polypipe water temperature control units.

All Polypipe under floor heating system packs supplied through
the selection process will contain all the appropriate
control products.

Modulating pump unit

(PB970014)

The modulating pump unit controls water temperatures between
45°C and 60°C. The inclusion of a modulating pump ensures
that the flow to the under floor heating circuits is automatically
adjusted to allow for the opening and closing of actuators
when individual room temperature is required. The unit is
suitable for manifolds demanding up to 15kW heat load.
The temperature of the water is set using the pilot pin on the
hand wheel. When the pilot pin is flush with the hand wheel
the temperature is set to 55°C. Each click to + or – increases
or decreases the temperature by 1°C.
The modulating pump unit is fitted directly to the manifold at
either end by turning the pump through 180°. An additional
zone valve is required when using a modulating pump unit
supplied by other manufacturers.

Floor heating control pack

(PB970015)

The pack controls water temperatures between 35°C and 60°C,
and incorporates a fixed head pump and a 22mm 2-port zone
valve, which is suitable for manifolds demanding up to 15kW heat
load. The set temperature of the water is shown on the wheel head.
The control pack is fitted directly to the manifold at either end,
as both left hand and right hand connector bends are supplied
with the unit.

Dimensions of assembled unit

NOTE:

The valves shown on this diagram are purchased

separately and not supplied with the unit.

Manifold bends (PB12735)

The water temperature control packs can be fitted at 90° to
the manifold using the manifold bends. This allows manifolds
and pump units to be corner mounted where space is at a
premium, e.g. in an understairs cupboard.

Manifold bend installed with modulating pump unit

Manifold bend installed with floor heating control pack

290mm

Pilot pin flush

to handwheel

260mm

155mm

110mm

50mm

30mm

130mm

40mm