Operating Instructions and Installation Instructions

ULTRAMAX PB 65 - 120
11 L290 ©MHS Boilers 13/12/2010
2.75 RVA47 Cascade Controller (Grey) & Housing
The RVA47 Cascade Controller (Grey) is a comprehensive
unit that can be wall or control panel mounted. The RVA47 is
supplied with 2 No QAD21 System Sensors (flow & return) and a
QAC32 outside air sensor. Each Ultramax PB boiler MUST be
fitted with an OCI420 Communication Clip-In Module, see item
17.4.
In addition to boiler control, the RVA47 can provide the drive
signal for a heating circuit pump and can provide control for
stored domestic hot water, with the RVA47 providing the
drive signal for a hot water primary circuit pump.
External control input to the RVA47 can be by either, a Volt Free
contact (e.g. time clock), 0-10v analogue input, a QAA70, QAA50
or QAA10 Modulating Room Unit.
Heating flow temperatures are weather compensated variable
(QAC32 supplied), if constant temperature is required, a 620Ω
resistor needs to be installed in place of the outside air sensor.
If more than twelve boilers need to be controlled, then additional
RVA47 Cascade Controllers can be connected to the first unit in a
„Master/Slave‟ arrangement. Each subsequent „Slave‟ RVA47
can control up to twelve boilers each.
Standard features include Pump Overrun, Boiler Load
Rotation, Frost Protection, and Pump Exercise program.
2.76 RVA46 Zone Controller (Black)
The RVA46 Zone Controller (Black) is a match controller for the
RVA47 (Grey), and is located in the Left-Hand position of the
RVA47 Housing.
The RVA46 can provide the drive signals for the Zone Circulation
pump and Mixing Valve (Supplied by Others).
If a mixing value is required to accommodate lower operating
temperatures from that of the other Zones, then a QAD21 flow
sensor will be required, available as an optional extra.
External control input to the RVA46 can be a QAA70, QAA50 or
QAA10 Modulating Room Unit.
2.77 RVA63 Zone Controller (Grey) & Housing
The RVA63 Controller (Grey) is a comprehensive controller that can
be wall or control panel mounted. The Ultramax PB boiler MUST
be fitted with an OCI420 Communication Clip-In Module, see item
17.4.
The RVA63 can provide the drive signals for two heating primary
pumps and mixing valves (if required) and can provide control for
stored domestic hot water, with the RVA63 providing the drive
signal for a hot water primary circuit pump.
If a mixing value/s is required to accommodate lower operating
temperatures from that of the other Zones, then a QAD21 or 26 flow
sensor will be required per zone, available as an optional extra.
External control inputs to the RVA63 can be by either, Volt Free
Enable contact (e.g. time clock), or QAA70, QAA50, QAA10
Modulating Room Units. An external control input is required per
zone. The RVA63 can also be linked to an RVA47 for Multiple boiler
installations.