Unvented Megaflo Strange Noise

[techweb]

Hi,

I have an unvented megaflo that it or nearby components make these strange noises shortly after drawing hot water and then shutting off. In this example, water was drawn for 10 seconds and then shut off. The noise continued for around a minute. I couldn’t find where it was coming from and no pipes were vibrating.

The boiler was not heating water at the time.

I have an external EV as well as the internal baffle in my scenario. I believe the internal baffle is in the process (or already) has disintegrated given the white deposits in some of the tap filters.

Any ideas?

Thanks in advance...

 

[John.g]

Possibly the PRV (pressure reducing valve) or, the expansion vessel, a bit of debris from the breaking up baffle may be partially blocking the piping from the EV to where its teed into the system but only possible if teed into the hot outlet, unlikely? or the EV may require the precharge pressure checked.

By the way, did you change the immersion heater themostat?. (your last thread).

 

[techweb]

Possibly the PRV (pressure reducing valve) or, the expansion vessel, a bit of debris from the breaking up baffle may be partially blocking the piping from the EV to where its teed into the system but only possible if teed into the hot outlet, unlikely? or the EV may require the precharge pressure checked.

By the way, did you change the immersion heater themostat?. (your last thread).

I have the thermostat ready to be changed and am waiting for my plumber to come and do this amongst some other jobs. One will also be to check out this strange noise. The EV is not teed into the cold outlet and is the other side of the PRV on the inlet.

I trust my plumber and he does a great job but it takes sometime to get him to come 🙂 Unless it's something critical.

 

[John.g]

Post a photo of where the EV is teed into the system.

 

[techweb]

Post a photo of where the EV is teed into the system.

I'll grab a picture when I get an opportunity to go into the loft again... Having said that, I e-mailed Baxi over the weekend regarding the cylinder and the baffle failure as realised it's under warranty. Even though I have no service history, they are sending an engineer to check it and determine next steps. I doubt they will do anything as apparently their usual fix is to install an EV (like mine has) and fit a filter on the hot outlet (I currently don't have).

Replacing the cylinder wouldn't be feasible without taking ceilings down given it would never fit through the loft hatch. It was put up there by the previous owners during a refurb.

At the very least they can check it out and for free 🙂 I'll even see if they will fit my replacement thermostat whilst at it.

Thanks for your help...

 

[techweb]

Today, Baxi (Heatre Sadia) came to inspect the cylinder and confirmed what I knew, that the baffle had failed. They offered to fit an inline strainer on the hot output but the guy said it will just block up very quickly so best just to leave as is or push for cylinder replacement. Won't be doing that as it's in a loft and a lot of work to remove / relocate. Not sure if they will have an alternative solution.

The noise is apparently the PRV doing it's thing.

The installation was confirmed as being very tidy and competent and the EV correctly placed.

 

[John.g]

Better to have a strainer blocking up than your mixers?, wonder does it then require a G3 to clean it.

 

[techweb]

Better to have a strainer blocking up than your mixers?, wonder does it then require a G3 to clean it.

I would doubt it but the guy said they aren't serviceable and would require replacing, in some cases after a few weeks.

They should come up with a way of cleaning the old baffle out in situ, wouldn't be impossible.

My taps / showers don't have any of those mesh things that clog up, just the kitchen tap. I clean it weekly. Not a big deal and I'm careful when I put new taps on that they don't have mesh things that can't be easily cleaned.