Camus Hydronics ADVANTUS AVH 500, Инструкция по установке, эксплуатации и обслуживанию

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3.3 INSTALL PIPING

The gas line should be sufficient to handle the total installed capacity. Verify pipe size with gas supplier.

Use new, properly threaded black iron pipe free from burrs. Avoid flexible gas connections. Internal diameter of flexible gas
lines may not provide appliance with proper volume of gas.

Install a manual main gas shutoff valve at the appliance gas inlet, outside of the appliance and before the gas valve. Install a
joint union at the appliance gas line connection for ease of service and removal of the gas train.

Run gas pipe to appliance gas inlet.

Install a sediment trap in the supply line to the appliance gas inlet.

Apply a moderate amount of good quality pipe compound.

For LP gas, consult your LP gas supplier for expert installation.
The appliance and its individual gas shutoff valve must be disconnected from the supply piping when pressure testing the gas supply
piping at pressures above ½ PSI.
Table 7: Gas Pressures at Inlet to Appliance
PROPANE NATURAL GAS
Minimum (inches W.C.) 11 4
Maximum (inches W.C.) 11 14
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 appliance. Sizing based on Table 6 is recommended.
Before operating the appliance, the complete gas train and all connections must be tested using soap solution.
Verify that the appliance is supplied with the type of gas specified on the rating plate. Heating values of local natural gas are to be
between 950 and 1010 Btu/ft
3
. Consult factory if heating values are outside this range or if a gas with a mixture of constituents is being
used.
3.4 AIR/GAS RATIO VALVE
Models 500 & 600 utilize a dual seat negative pressure air/gas ratio control valve. Operation of the gas valve in combination with the
combustion air fan allows the burner input rate to vary from 10% to 100% based on temperature demand.
Model 800 utilizes a low end and a high end dual seat negative pressure air/gas ratio control valves. Operation of the valve in combination
with the combustion air fan allows the burner input to vary from 4.5% to 100% based on temperature demand. At a pre-determined point
control is passed from the
Low-End Valve to the High-End Valve and at the same time the fan air Inlet Damper is gradually opened.
Models 1000 - 4000 utilize a dual seat negative pressure air/gas ratio control valve at the low end and an air/gas ratio control valve at the
high end. This combination allows the
Low-End Valve to fire down to 4.5% for the AV1000 - 1800 and 4.0% for AV2000 and above of
full input to achieve a 22:1 and 25:1 turndown, respectively. At a pre-determined point control is passed from the Low-End Valve to the
High-End Valve and at the same time the fan air Inlet Damper is gradually opened. The High-End Valve controls the pressure difference
across a flow orifice in the manifold supply line as a function of the pressure difference across the combustion air supply to the burner.
The
High-End Valve actuator maintains a matching 1:1 air to gas ratio as the volume of air changes based on the operation of the
combustion air fan.
The air/gas ratio of both low and
High-End Valve s is preset at the factory and adjustment is not usually required if gas supply pressure is
maintained within the specified range.
There are no serviceable parts on the dual seat negative pressure air/gas ratio control valves.
A reduction of up to 30% is permitted in the inlet gas pressure between light off and full fire conditions.
If the manifold differential pressure is to be measured, refer to section 3.8 Checking Differential Air and Gas Pressures for Proper
Measurement.