Boiler Pressure Dropping

BalboBiggins

Hi guys, I recently renovated my home and the pressure in the new boiler is dropping every month or so. I presume this means there is a leak somewhere in the system and I'm wondering if there is any way to locate this without tearing the house apart?

DOCARCH

Mod Note: May be more appropriate for plumbing forum.

DublinDilbert

What was replaced on the renovation?

Does it drop gradually or seem ok for weeks then drop in one go?

On a recent renovation I had an issue with boiler pressure dropping occasionally, it could be ok for a few weeks, then it would drop. I traced it down to the water not having any path, when the zone valves turn off, so seemed to be venting off via the 3 bar release valve. There was no automatic bypass fitted, so i just opened the flow the hot cylinder (not zoned). Since I increased the flow to the hot cylinder, the pressure hasn't dropped in 3 months (or so).

Find the pipe from the 3 bar pressure release valve and place a balloon or rubber glove on it. If anything vents off, this will fill with water.

Yellow_Fern

I had the same thing. I found it as there was tiny streak of rust on a rad's blanking plug. That was enough to cause pressure loss.

BalboBiggins

Thanks lads, it's fine for three or four weeks, then drops in one go. I will review your suggestions and hopefully that might solve it.

Yellow_Fern

https://www.boards.ie/discussion/comment/120442144#Comment_120442144

That timing was just like mine. Def check your rads and all joints for corrosion where a leak might occur