6
ORIGINAL INSTRUCTIONS
VES Andover Ltd Eagle Close Chandlers Ford Ind. Est Eastleigh Hampshire SO53 4NF
Tel: 08448 156060 Fax: 02380 261204 E-mail: vesltd@ves.co.uk Web: www.ves.co.uk
Installation, Operation and Maintenance Manual
®
EVC
Heat Recovery Unit
Continued
On
EVC/ -E
units, an electric heater battery (EHB) will be installed. Supply to the heater should be
1Phase or 3Phase with separate neutrals; confirmation 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.E. Regulations
, ensuring a sufficient earth connection 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 manual-reset high temperature cutout with normally closed (NC)
terminals and is set to break if the duct temperature rises above 130 °C.
It is important that the cutout is connected to the safety circuit so the heater is isolated in the
event of overheating caused by airflow failure.
The electrical supply must be isolated before attempting to reset the manual cut-out and should
be given sufficient time to cool. For further information 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 battery. Suitable
speed controllers without on/off switches are available from VES Andover.
Coils should be piped according to any relevant local codes of practice. Where threaded
connections are supplied, the only approved method of jointing method is by use of Boss white
and hemp. The thread fitted to the coil is to be supported at all times 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
conditions during the winter season. If the water is allowed to freeze in the coil system,
damage may occur potentially bursting pipes and resulting in emergency problems.
Fitting a frost thermostat at the unit inlet and ensuring that boilers run continuously in low
ambient temperatures can help to prevent this.
Heating coils do not cool immediately when the hot water supply is cut off. The residual heat
must be dissipated to avoid damage. The continuous running of the fan after shutdown
resolves this, by operation of a run-on timer.
The recommended length of run-on is
2 minutes minimum
.
On Ecovent®
EVC / -W
units, a Low Pressure Hot Water (LPHW) coil will be installed. The coils are
normally suitable for LPHW at 82 °C flow and 71 °C return temperature. LPHW coils are supplied as
standard with an air vent and drain plug located on the pipe work immediately adjacent to the coil
connections 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 potential air locks, resulting in a fall off of duty.
Installation
4
Typical LPHW Coil
Fig.
12
Caution
Coils
Electric Heater
Batteries
Caution
LPHW Coils
Flow
Return
Caution
It is recommended that a check be made as to
whether any treatment is required to the water
supply for prevention of corrosion and scaling of
the equipment. Information regarding the necessary
action to be taken can be obtained from the relevant
Local Water Supply Authority.
The unit will have been supplied with connections
either left or right-hand side looking in direction of
airflow. Please see order acknowledgement for
confirmation of this handing. Should you need to
alter this please consult VES as unit adjustment may
invalidate your warranty.
Airflow
