BENSON MH300, User Instructions

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(l) Repeat steps 4.2 d,e,f, allowing the heater
to reach thermal equilibrium.
(m) Adjust thermostat to its highest setting,
and allow the heater to continue to fire.
(n) Gradually reduce the temperature setting
on the thermostat until the burner shuts down,
(@ < ambient and then gradually increase the
temperature setting on the thermostat until
heat is called for, (@ > ambient) and the
burner automatically re-fires.
(o) Check fan and limit stat by depressing and
holding in the fan motor overload re-set button,
located on the heater electrical panel. The time
between the fan stopping and burner shut
down should be noted, once the burner has
shut down the overload on the motor should be
released.
If the time interval between fan stop and
burner shut down is greater than 90 seconds
further checks should be made.
These are as follows
(i) Check settings on fan and limit stat are
correct, ie, fan on 60oC, fan off 30oC, limit
100oC.
(ii) Check that the position of the unit is
correct, ie, equi-distant between heat
exchanger body and heat shield panel.
(iii) Check integrity of unit, ensuring that
neither the bi-metallic strip nor its casing is
damaged.
(p) Undertake flue gas analysis using
approved and calibrated analysing equipment
recording data on the commissioning card, ie,
CO, CO2, net and gross flue temperatures.
Record burner oil pump pressure, ambient
temperature, barometric pressure, and smoke
reading (0 - 1 Baccarach scale).
Note (i)
The burner air and oil pressure settings should
be only very finely adjusted to achieve a CO2
reading of 12.5%
(+/- 0.5%).
Note (ii)
The gross efficiency must be approximately
80%.
Note (iii)
All Heaters are test fired and pre-
commissioned as part of the manufacturing
process, if however, during on site
commissioning the data are found to be not in
accordance with the manufacturers data, then
the following action is recommended.
* Re-check all readings and calculations.
* Adjust burner as per manufacturers
instructions.
* Consult Benson Technical Department.
(q) Complete commissioning card and provide
operating instructions for the user, high-light
the fact that the manufacturer recommends
that in the interests of safety and efficiency the
heater is serviced on a regular basis only by
qualified and competent persons.
The completed commissioning card must be
returned to Benson Heating Service
Department immediately after the satisfactory
completion of commissioning, failure to do so
can invalidate any subsequent warranty claim.
(s) Set all controls to the requirements of the
user.
4.3 Commissioning - air delivery system
Caution
On ducted applications it is necessary that the
system is balanced in order to optimise the
efficiency of the heater and the air distribution
and delivery system
Failure to balance the system can result in fan
motor overloading and premature component
failure, it can also result in an inefficient
heating/ventilation system.
(a) Check that the amount of fan produced air
volume is in accordance with the heater
specification; if the volume is too great the fan
can be overloaded.
Ensure that the running current is as per that
stated on the heater data plate.