Problem with hot water - Calling all pluimbers

[FlyingDuck]

I got this problem with my hot water. Sometimes it works fine, with nice pressure, but at other times, particularly in the evening I have noticed, the pressure reduces to barely a drop. In fact, tonight it just about stopped.

When the pressure reduces like this, it also makes a horrible squealing noise through the pipes around the house.

I guess something must be blocking it somewhere, but can't understand why sometimes it runs normally, and while at other times there is just about no flow. The temperature is always hot, it seems that it is only the flow being affected.

Short of calling a plumber, I would like to have a go a fixing the problem myself, but don't know where to start.

[glock40sw]

G'day Duck.
Do you have one of those hot water safety flow restrictors in the pipework in you roof?

We have them fitted to the shower heads, bath outlets and hand basins.
It is to prevent hot water burns. If the hot is left running, the arrestor stops the flow of hot water. If you turn the hot tap off, and the cold on, the water will flow again.
My plumber said that some houses have only 1 fitted in the pipes in the roof cavity.

Hooroo.
Regards, Trevor
Grafton

[FlyingDuck]

Yeah, I know what you are talking about, but am pretty sure that I don't have one of these and that this is not the problem. My hot water was running great for the first 3 years I owned this house, and the problem has only been happening for about a couple of months now.

I think maybe something else is restricting it. Maybe some sort of dirt or growth in the piping somewhere. I just dunno.

[journeyman Mick]

Flying Duck,
on the inlet side of your HWS is a valve. It may be a 3 in 1 multi valve: stopcock, pressure limiter and strainer or these three functions may be performed by three seperate units. I'm guessing theres a lot of particle build up in the pressure limiter (possibly there's no strainer, or it's full up). Pressure limiters can make some horrible whistling and groaning noises so this is possibly where the noise is coming from. If there's a strainer fitted you should be able to unscrew a cap and remove the strainer for cleaning (after shutting off the mains). This may fix it, otherwise it may be possible to remove and clean out the pressure limiter with compressed air. Hope this helps,

Mick

[FlyingDuck]

Thanks Journeyman, I'll give it a go today & see what happens.

Duck

[doug the slug]

I got this problem with my hot water.

sorry but ive gotten myself into enough hot water this week, im not touching this one.

Doug

[soundman]

here's a well ignored fact.
All those valve thingy's that hang arround on the pipes to & from your hotwater system have limited service lives & will be stamped with a date.
If it is a mains preasure unit it will also have a sacrificial anode it the top.
All these items "should" be replaced every something like 5 to 10 years.
Never happens.
I now know why this house has had 3 HWS in less than 20 years.
Just a but of usless information.

[Harry72]

Not a continous heat unit is it?
These have a pressure sensitive valve, cracks in the diaphram will bring water flow to a stop, it regulates the water flow through the heating core.

[FlyingDuck]

Looks like I've got some valve thingy replacing to do.