# How to use a gas test gauge to check the pressure of appliances?

One of the main purposes of gas test gauges is to check and set the correct gas pressures on gas appliances such as boilers, cooker hobs or tumble dryers.

They can also be used to check the standing and working pressures of a gas meter.

## How to check the standing pressure of a gas meter?

### Step 2 - Turn on Gas

Turn the gas on slowly. Take a reading from the gauge.

The value shown is the standing pressure of your meter.

It should be around 25 mbar.

Wonkee Donkee says: When reading a gas test gauge, make sure that you look at both columns; the reading on both should be the same. If they differ, reset the gauge by adjusting the zero adjuster or average the readings by adding them together and dividing them by two.

## How to check the standing pressure of a gas meter?

The working pressure of your meter should also be tested as part of a gas safe test. The working pressure (or operating pressure) is the pressure of the gas provided by the meter when it is in use and appliances are working.

### Step 1 - Turn on appliance

Turn on one appliance (usually the boiler). The gas should be on full.

### Step 2 - Read Gas Test Gauge

Take a reading from the gas test gauge. The working pressure of most meters should be between 19 mbar and 23 mbar. The pressure of this meter is 20 mbar, so no further action needs to be taken.

If, however, the reading on the gauge is above or below this range you may need to take one of the following actions:

If your gas meter is a primary meter, contact your gas supplier.

If it is a secondary meter, you will be able to manually adjust the pressure.

## How to check the inlet working pressure?

After checking the standing and working pressures of a meter, a gas engineer will usually test the inlet working pressure of the boiler.

This test will ensure that the pipework connecting the gas meter to the boiler is the right size and has no blockages.

### Step 1 - Connect test gauge to boiler

Connect a zeroed gas test gauge to the boiler inlet test point.

### Step 2 - Turn on boiler

Turn on the appliance and record the reading shown on the gauge.

The difference between the working pressure at the meter and the inlet working pressure should be no more than 1 mbar.

E.g. if the working pressure at the meter was 21 mbar and the inlet working pressure was 20 mbar, then the installation would be acceptable.

If there is a greater discrepancy than 1 mbar, then there is a problem with your boiler which will need to be repaired by a plumber.