Testing Combi Boiler Gas Pressures

[Sparky]

On full flow my DHW on my Baxi Bahama 100 is at a lower temp than is usual - only about 35 degrees C.

I have checked the modulating current and it is at 130mA as per the technical manual - all ok there

I want to check I have the correct gas modulator pressure - I have a pressure meter that will read the pressure of 13.6mBar and I think the pressure test point is the one with the small rubber cap. There is also a hole next to this with a brass screw in the bottom. Do I need some kind of special hose/adaptor to connect to the pressure test point or is the pressure test point the one with the brass screw? In my service manual it shows the test point as being the one with the rubber cap.

Any help appreciated

[andrewpreece]

Can't help you with the test point but I used a u-tube manometer made with clear vinyl tube to measure my combi modulation pressure, the tube being probably 1/4" diameter. It is sufficiently pliable to be pushed onto a variety of diameters of pipe whilst still being gas-tight.

Andy.