Technical data

9.2.2 Gas valve/ ignition block

Note: The gas valve is factory-preset and therefore only Atmos or their

agents can supply these.

Remove the spark ignition block by pulling apart horizontally. Undo the

upper and lower unions, making sure that the ‘O’ rings and gas setting ring

are not lost or damaged (see diagram in §7.7). Replace the gas valve, and

refit the ‘O’ rings, the gas setting ring, the unions and the ignition block.

Note: After replacing the gas valve, carry out the gas analysis adjustments

and the CO/CO2 ratio check as given in §7.9 and §7.10.

If replacing the ignition block, then pull apart as above. Remove the push-fit

cable to the probe and undo the X1 connections at the controller and earth.

Replace the ignition block and make the connections.

9.2.3 Fan

Remove the electrical connector. Undo the upper union from the gas valve.

Undo the two 8mm nuts as shown in the photo. Remove the assembly

including the sealing ring. Undo the three Allen screws (M4x10) to remove

the gas inlet sub assembly. Fit the replacement fan in reverse order. Check

the sealing ring is not damaged and replace if necessary; check that it seals

correctly.

See also §9.2.4 below for appliances fitted with Non Return Valve (flue

gas).

9.2.4 Note for CFS systems with Non Return Valve (flue gas)

When refitting the fan, the NRV MUST be refitted (see diagram). Fold the

silicon valve (1) of the NRV carefully into a U-form.

Place the valve + holder (1+2) into the hole of the front plate, making sure

the valve is placed in the correct position (direction toward the front plate as

shown).Replace the fan + seal back on the front plate, and screw both nuts

(4) tight, making sure the valve stays in the right position.

9.2.5 Controller

If possible, record the parameter settings as described in §7.3. Remove the

display cover and undo the two posidrive screws to drop down the controller

panel as shown in the diagram in §5.3.

Pull apart the connectors and undo the 8mm nut to allow the controller

assembly to be removed and replaced. After replacement, set the required

parameter settings as described in §7.2and §7.3,

Note

The ignition block is held on the gas valve

by a Torx T10 screw. Remove this screw

prior to pulling the ignition unit off.