Plumbing - Pipe from boiler to outside leaking.

milltown

There is a pipe from my gas boiler in the kitchen that runs to the outside, where it is open. There is a pretty constant drip from it. Even on a dry, sunny day there will be a small puddle under it. House and all associated services are three years old. Standard, modern 4 bed semi in an estate.

Should I be worried?

I know there's probably a raft of info needed for a decent diagnosis but I'm guessing it's a vent for pressure relief or something. If I take off the boiler cover will it be a simple case of nipping a relief valve or something.

311

That really could be anything from an opened valve to a damaged vessel.
Get a service done on it ,let the guy know that the valve is leaking though when you call them.

milltown

Have done a bit more digging online and found that the cause of the leak is the heating safety valve, a relief valve, factory set to vent at 3 bar. I removed the valve to inspect it and there was black gritty dirt stopping it from seating properly. Cleaned it and replaced it and there's a big improvement, although still the odd drip. I'll pick one up during the week and replace it with a new valve.

Now, once all that was done and the valves were opened again I could hear the water flowing into the boiler again and it fired first time. It worked for a short while then errored out for low pressure, showing 0.5 bar on the boiler display. I had a similar problem when we moved into the house and the plumber told me to adjust a pressure regulator in the hot press. I wound it in a bit and all was good again.

The heating never came on this morning and the low pressure error was showing again. There's a guage beside the regulator in the hot press and when adjusted to show 1 bar at the boiler the guage reads ~2 bar.

The boiler is a Gloworm 18Si and depending on which web page you read does or doesn't have an internal filling loop. Do I need one of these: to properly fill the boiler to the correct 1 bar pressure? What is the purpose of the reg. and guage in the HP if not to set the system pressure? And why the discrepancy between boiler and guage readings?

Thanks in advance to anyone who can answer some or all of my questions!

landydef

the filling loop just consists of an isolation valve and a non-return valve so it wont help to regulate the pressure
it might be worth twisting the small cap on the bottle-vent just above the pump in the boiler as when you drain down the boiler air usually gets in.
you may still have to fiddle around with the pressure reducing valve in the hot press to rise the pressure,usually there is a plastic knob on one side and a flat-head screw on the other