7
ecovent Duct Mounted Heatersmini
Connued
On ecovent /-E units, an electric heater baery (EHB) will be installed. Supply to the heater
should be 1Phase or 3Phase with separate neutrals; confirmaon of this can be found on the unit
nameplate. Cables should be of silicone rubber, fibreglass or of a similar high temperature
insulated type and be installed to current I.E.T. Regulaons, ensuring a sufficient earth connecon
to the terminal provided. Care should be taken not to overstrain the terminal pillars as this may
permanently damage the elements.
The heater is fitted with a thermal cutout which will break contacts when the duct temperature
rises above 70 °C.
It is important that the cutout is connected to the safety circuit so the heater is isolated in the
event of overheang caused by airflow failure.
The electrical supply must be isolated before aempng to reset the manual cut-out and should
be given sufficient me to cool. For further informaon regarding electric heaters please see
VES Ref. ID431.
If a speed controller is fitted to the system, it must not stop the fan independently of the control
system, or allow airflow to fall below the stated volume on the electric heater baery. Suitable
speed controllers without on/off switches are available from VES Andover.
Coils should be piped according to any relevant local codes of pracce. Where threaded
connecons are supplied, the only approved method of joinng method is by use of Boss white
and hemp. The thread fitted to the coil is to be supported at all mes whilst making joints. All
external piping is to be supported independently from the coil. Fluid filters are recommended.
It is important that water and steam coils are protected against damage from extreme weather
condions during the winter season. If the water is allowed to freeze in the coil system,
damage may occur potenally bursng pipes and resulng in emergency problems.
Fitng a frost thermostat at the unit inlet and ensuring that boilers run connuously in low
ambient temperatures can help to prevent damage.
Heang coils do not cool immediately when the hot water supply is cut off. The residual heat
must be dissipated to avoid damage. The connuous running of the fan aer shutdown
resolves this, by operaon of a run-on mer.
The recommended length of run-on is 2 minutes minimum.
On ecovent / -W units, a Low Pressure Hot Water (LPHW) coil will be installed. The coils are
normally suitable for LPHW at 80 °C flow and 60 °C return temperature (see the unit outline
drawing for confirmaon). LPHW coils are supplied as standard with an air vent and drain plug
located on the pipe work immediately adjacent to the coil connecons on the AHU. The air vent
should be at the highest point, with the drain at the lowest. The coil should be regularly vented so
as to avoid potenal air locks, resulng in a fall in duty.
Typical LPHW Coil
Fig. 6
Cauon
Coils
Electric Heater
Baeries
Cauon
LPHW Coils
Flow
Return
Cauon
It is recommended that a check be made as to
whether any treatment is required to the water
supply for prevenon of corrosion and scaling of
the equipment. Informaon regarding the necessary
acon to be taken can be obtained from the relevant
Local Water Supply Authority.
The unit will have been supplied with connecons
either le or right-hand side looking in direcon of
airflow. Please see order acknowledgement for
confirmaon of this handing. Should you need to
alter this please consult VES as unit adjustment may
invalidate your warranty.
Airflow
Installaon 4
