Gas Supply And Piping - Camus Hydronics MFH060 Installation, Operation And Service Manual

As the modulating fan ramps up, gas input is adjusted accordingly to match the airflow. When the call for
heat ends, the valve is de-energized, and the fan modulates off.
Normal Operation
Modulation is controlled from the Boiler Temperature Controller. The modulating fan is equipped with an
electrically commutated DC motor which responds to a PWM signal.
The control provided with the Modulating MicoFlame allows remote control with an analog signal of 4-
20mA or 2-10VDC.
Demand Satisfied
The BTC 1 senses that the boiler target temperature was reached and de-energizes the stage contact.
Control Alarms
High limit or low water flow will de-energize all gas valves, and the blower. Condition indicators are visible
on the control panel. Each burner/blower set is provided with its own air pressure switch. If a low air
pressure condition is present, power will not be supplied to the ignition module. The blower will remain on
and the air indicator will remain on for as long as there is a call for heat. If the safety proving sequence
does not proceed to completion, the first safety light to remain off will indicate the cause of the problem.
All other lights below the problem indicator light will also remain off.
6

GAS SUPPLY AND PIPING

This boiler is intended to operate at inlet gas pressures not exceeding ½ PSI (14" W.C.). If higher
pressures are present, consult the gas company for correction.
When pressure testing the gas supply piping at pressures above ½ PSI, the boiler and its individual gas
shut-off valve must be disconnected from the supply piping.
Provide a trap (drip leg) as close to the heater as possible.
Install a ground joint union and manual shut-off valve in the gas line near the heater to allow easy
removal of the gas control assembly.
Provide gas pressures at inlet to boiler gas train as follows:
Minimum Running
(inches W.C.)
Maximum Lockup
(inches W.C.)
The gas supply line must be of adequate size to prevent undue pressure drop and must never be smaller
than the size of the connection on the heater. Sizing based on Table 4 is recommended.
Before operating the boiler, the complete gas train and all connections must be tested using soap
solution.
Table 3: Gas Pressures to Inlet to Appliance
PROPANE NATURAL
10
11
5
GAS
4
14