Boiler gurgling

[Cara]

We have an ideal istor he260 boiler and it has just started making a gurgling water noise. Took off the from cover and on a pipe labelled DHW PRV there is a black plastic part half way up with holes in it either side and we can see a flow of water there with steam coming out. No idea what this is and never seen before. Is this dangerous? Pressure is v slightly over 1.5. Any help greatly appreciated

 

[sellers]

Sorry I can saw weather the steam is dangerous, but possible air locks can make your central heating noisy.

 

[NozSpark]

Well, a DHW PRV is a "Domestic Hot Water Pressure Relief Valve" and it shouldn't be operating under normal circumstances...

Is your hot water the same as usual or hotter,, maybe a thermostat has been altered or has broken?

 

[Cara]

Thanks. The water temperature does not seem any different to be honest. It now seems to be operating totally ok. No gurgling, no water spraying and no steam. Maybe it's corrected itself? Thanks so much for response. Not used this forum before so it's great to know assistance there!

 

[a1]

You're welcome Cara.

 

[DarkInferno]

your dhw pressure is too high... possible faulty thermostat, dhw expansion vessel (if it has one), or pressure reducing valve.

 

[kme]

If the PRV has re-sealed, then there WAS an issue; which is now resolved. Those valves are usually set at 3 bar; but the outflow is normally tied into an overtemperature relief valve (sometimes combined at a TPR valve). The idea is to stop the storage vessel rupturing as a result of excessive pressure build-up; OR over-expansion caused by overheating; itself a symptom of a failed thermostat (usually operate at 88 or 92 degrees, if I remember correctly.)

The fact that the water was steaming would suggest it was an overheat issue - if it re-occurs, a heating engineer visit is recommended.

note: similar to an RCD, these units should be periodically operated (the knurled knob on the top is rotated approx 1/4 turn (they are fitted with recoil springs; so a resistance will be felt) ; water should exit the pipe. release the knob, the valve shuts and you have confirmed mechanical operation of the valve.

One final note. The wax capsule which operates the overtemp. device can become inoperative due to overtemperature, as I recall.

Hope that helps.

KME

 

[Cara]

Thanks for all the advice. Returned home and as soon as the heating has kicked in it has started flowing again and a much greater flow that I would describe as like a tap turned on full. Will call out the plumbers as now it's recurring there must be a issue perhaps with the thermostat as described. Really appreciate the assistance thanks guys

 

[a1]

You're Welcome Cara.