A water flow switch meets most code requirements for a
TABLE I
MINIMUM FLOW RATE REQUIRED TO
ACTUATE FLOW SWITCH
Pipe Size | GPM Flow Rate |
|
|
1 1/2" | 13 |
|
|
2" | 18 |
|
|
LOW WATER CUTOFF (IF EQUIPPED)
A hot water boiler installed above radiation level must be provided with a low water cutoff device either as part of the unit or installed at the time the boiler is installed. An electronic low water cutoff is available as a kit on all units. Low water cutoffs should be inspected every six months, including flushing of float types.
TWO STAGE BURNER
CONTROL SYSTEM
The 45,000 thru 500,000 Btu/hr boilers (M9) are equipped with a two stage burner control system. The 45,000 thru 399,999 Btu/hr models will be equipped with a two stage gas valve to control high/low burner operation. The 500,000 Btu/hr model achieves two stage burner firing by staging the operation of the two combination gas valves.
4.To avoid serious damage, DO NOT energize the appliance until the system is full of water. Serious damage may result.
5.Provide the unit with proper overload protection.
6.Install a wall thermostat on the inside wall. DO NOT install the thermostat in an area affected by drafts, sunlight, light fixtures, hot or cold water pipes or near a fireplace. See “Terminal Strip Con- nection of a Room Thermostat”, page 38 for proper wiring connection.
TABLE J
AMP DRAW DATA
45,000 thru 500,000 Btu/hr Models
MAXIMUM
FIRINGTOTAL AMPS
CONTROLS | @ 120 VAC |
|
|
F1 Standing Pilot (Single Stage |
|
90,000 - 260,000 Btu/hr) | 2.5 |
F9 Intermittent Pilot (Single Stage |
|
90,000 - 399,999 Btu/hr) | 2.5 |
|
|
F9 Intermittent Pilot (Single |
|
Stage/2 valves 500,000 Btu/hr) | 2.5 |
|
|
M9 with Internal Pump |
|
(45,000 - 260,000 Btu/hr) | 2.0 |
|
|
M9 Intermittent Pilot (Two Stage |
|
Valve 315,000 - 399,999 Btu/hr) | 2.0 |
|
|
M9 Intermittent Pilot (Two Stage/2 |
|
valves 500,000 Btu/hr) | 2.0 |
ELECTRICAL CONNECTIONS
This appliance is wired for 120 VAC service. The appliance, when installed, must be electrically grounded in accordance with the requirements of the authority having jurisdiction or in the absence of such requirements, with the latest edition of the National Electrical Code ANSI/NFPA No. 70. When the unit is installed in Canada, it must conform to the CSA C22.1, Canadian Electrical Code, Part 1 and/or local Electrical Codes.
1.All wiring between the appliance and field installed devices shall be made with type T wire [63° F(35° C) rise].
2.Line voltage wire exterior to the appliance must be enclosed in approved conduit or approved metal clad cable.
3.The pump must run continuously when the appliance is being fired.
Pump Wiring for a Heating Boiler
The heating boiler circulating pump must be purchased locally. The maximum load for the pump switched by the internal pump relay must not exceed 1 HP. The current draw for a field installed 120 VAC pump MUST be added to the boiler’s current draw to determine the minimum wire size for 120 volt service.
FIG. 25 Standing Pilot System F1 Control Panel
19
