Lochinvar CP-M Series User Manual

34
10.3 SEALED SYSTEM ARRANGEMENT
If a sealed system arrangement is required, a suitable pressurisation unit is available from Lochinvar Limited on request. Sealed
systems should incorporate a safety valve with a lift pressure no greater than the maximum pressure rating of any component in
the heating system. The maximum working pressure of the boiler is 6.0 bar. A suitably sized expansion vessel should also be
fitted to the system in accordance with BS4814.
The appliance is fitted with a water pressure sensor and requires a nominal system pressure of 1.0 bar. The burner control will
block the boiler from operating if the system pressure drops below a pressure of 0.8 bar; once the system pressure rises above
1.0 bar, the block will be lifted. The maximum system pressure with the standard pressure sensor is 4.0 bar however, a pressure
switch may be used if the static head exceeds this. For further details on the connection of a water pressure switch, please refer
to Section 11.0: ELECTRICAL SUPPLY.
10.3.1 EXPANSION VESSEL SIZING
The following information is based on a static head of 3.5 bar. If a different cold fill pressure is to be used, please consult
BS4814.
V V = S V * e
0.45
Where:
V V = Vessel Volume
S V = System Volume
e = Coefficient of Expansion (See Table 10.1)
Stored
Temp.
C
30
35
40
45
50
55
60
e
0.005
0.006
0.008
0.010
0.012
0.015
0.017
Stored
Temp.
C
65
70
75
80
82
85
90
e
0.020
0.023
0.026
0.030
0.031
0.033
0.037
TABLE 10.1 COEFFICIENT OF EXPANSION OF WATER AT 3.5 BAR COLD FILL PRESSURE
10.4 CIRCULATING PUMPS
The CP-M+ boiler has a built in circulating pump. This pump has a speed regulator which has been adjusted to the maximum
setting. To prevent operational issues, this setting must not be altered.
When there is a call for heat, the pump is energised, once the call for heat expires, the pump overruns for a period of 3 minutes.
The pump is also activated for one minute every 24 hours after the boiler power supply is connected in order to prevent the pump
seizing.

Lochinvar CP-M Series Specifications

General

Brand	Lochinvar
Model	CP-M Series
Category	Boiler
Language	English