Brown Hot Water

ART6

brettmirl wrote: »

Hi Art6.

The plumber got me to close that red valve above the NR valve to see if it made any difference (it had been fully open). It's been closed since last night, so will see what happens.

Seems he is thinking along the same lines. So let's see what happens with the boiler pressure.

JamesM

ART6 wrote: »

Seems he is thinking along the same lines. So let's see what happens with the boiler pressure.

I've got a cold, so the head isn't working too well at the moment. But I agree with Art's recent posts. One other thing, if the pipe that the red valve and non return valve are on, comes from the same tank in the attic as the hot water, and not an expansion tank (is there an expansion vessel anywhere ?) then the water might have been pushing up past the non return valve and into that tank. Unlikely, but the brain is a bit frazzled at the moment.
Jim.

brettmirl

I turned on the boiler when I got home and checked which pipes got hot immediately. See attached pic for my dodgy editing!

Pressure ok so far and no change in water colour...it's not gotten any worse as yet.

brettmirl

JamesM wrote: »

I've got a cold, so the head isn't working too well at the moment. But I agree with Art's recent posts. One other thing, if the pipe that the red valve and non return valve are on, comes from the same tank in the attic as the hot water, and not an expansion tank (is there an expansion vessel anywhere ?) then the water might have been pushing up past the non return valve and into that tank. Unlikely, but the brain is a bit frazzled at the moment.
Jim.

Hey JamesM. A few hot whiskeys tonight will sort that cold for you!

I've checked the tank in the attic a few times since all this began, and each time the water in it has been clear.

That red valve abover the non return is currently closed.

ART6

brettmirl wrote: »

I turned on the boiler when I got home and checked which pipes got hot immediately. See attached pic for my dodgy editing!

Pressure ok so far and no change in water colour...it's not gotten any worse as yet.

OK. If the boiler circuit water was escaping into the tap water somewhere then with the red make up valve closed the system pressure would not increase when the boiler is on -- it would never rise above what it is with the boiler off. There would be some flow of water from the boiler circuit into the hot water system when the boiler lights and its water expands, and a flow in the other direction when the boiler is off and its water cools. That would suggest that the maximum flow between the two would probably be less than half a litre, so the end result might not be that the hot tap water clears completely, but only that it does a fair bit and doesn't get worse. So, does the pressure rise when the boiler lights or does it stay the same? If so, what is the gauge reading and how far above the floor on which the boiler stands it the bottom of the attic tank. I'm guessing that the cylinder is upstairs and the boiler is at ground level?

Oh, and JamesM I agree entirely with the OP about the cold treatment and would strongly recommend it. In fact I find that a steady supply of whiskey is an excellent preventative measure:D

JamesM

Thanks lads. One question, if the pipe no. 4 in Art's photo is the return from the coil to the boiler, why is it not hot ? Another, is the 1/2" pipe near the top of the cylinder the cold water feed to the cyl (fed down inside), or is there another connection on the right hand side at the bottom ? Or is that 1/2" pipe just another hot water pipe going to a shower or something. And, does the pipe with the red valve and NR valve go straight into the main tank in the attic.
Jim.

ART6

Going by the pic in OP's post #34 pipe #4 must be hot too since there doesn't seem to be anything to prevent it being. I just assumed he hadn't marked it. Since we believe we have identified the black levered valve on the braided hose as being the coil bypass, I wonder if opening it again would take some of the flow away from the coil and, if there's still a leak anywhere there, cut down on the water cross-over? Mind you, I haven't though that through!

brettmirl

ART6 wrote: »

So, does the pressure rise when the boiler lights or does it stay the same? If so, what is the gauge reading and how far above the floor on which the boiler stands it the bottom of the attic tank. I'm guessing that the cylinder is upstairs and the boiler is at ground level?

Hi ART6. Am in a typical 3 bed semi-d. The boiler is on the ground floor (wall mounted), the hot water cylinder is upstairs, and the water tank is in the attic.

The gauge reading on the boiler...there are two scales on it; one reads 0 to 4 and the other in red goes 0 to 60.

When the heating is off the needle is at zero. When I turn boiler, it immediately jumps to just below 1 (or 10 on the other scale) and when the heating reaches its top temp, the needles is at 1.5 (or 20).

After the boiler turns off, the needles slowly drops back to zero.

The boiler is a Sirrus Radiant RS20E.

items

Some of the advice here is way off the mark. Its hard to follow.

Two things worth mentioning, the flexi hose with the little black handle is a by-pass and should be open slightly. You have a heat control (thermo valve) on your cylinder flow, when cylinder is hot enough it shuts off circulation to the cylinder. The by-pass must always be open, if you happen to shut off the rads and turn on the boiler, you'll have no circulation. You'll damage pump at boiler or worse, blow up the boiler.

The red handle gate valve above the NRV(brass cylindrical fitting) is your heating filler, it must also remain open at all times.

brettmirl

JamesM wrote: »

Thanks lads. One question, if the pipe no. 4 in Art's photo is the return from the coil to the boiler, why is it not hot ? Another, is the 1/2" pipe near the top of the cylinder the cold water feed to the cyl (fed down inside), or is there another connection on the right hand side at the bottom ? Or is that 1/2" pipe just another hot water pipe going to a shower or something. And, does the pipe with the red valve and NR valve go straight into the main tank in the attic.
Jim.

Pipe #4 didn't get hot immediately like the pipes I marked did once the boiler came on.

items

The only place heating water can mix with hot water is inside the cylinder or related pipe work. Turning valves on and off wont solve the problem. The problem is being crated after the valves.

From what I believe you've had your cylinder replace? If so, that should rule out the cylinder.

It's possible heating pipe work and hot water pipework have some how been connected to each other, might have always been this way, you only notice now due to system being older, heating water has changed color over the years and only noticeable now.

To rule this out, your going to have to get a plumber to test heating system for leaks, easily done, connecting a hand pump with gauge to the heating system.

Like wise I would test the hot water pipe work for leaks, its another possibility. You could have a small leak in pipework under ground and its drawing in some dirt etc, giving the water that brown color.

Call the plumber back who replaced the cylinder, I am sure you got him/her in to fix the brown water problem, it doesn't seem to be fixed, he or she didn't do the job right and should return to do it right.


Just had a look at your pictures, you've a standard modern heating system, no big mysteries. Sometimes all the pipe work can throw people off, all you have to do is break it down. Heating pipe work comes directly into the hot press, from the hot press it is then divided to serve cylinder and rads. You've got some option of heating control which has only become available in Irish heating systems in the last 10 years or so.

You can choose to just heat your cylinder during the summer by turning off the rads (red lever action valve) when the cylinder is hot enough the thermocouple connected to the cylinder sends a signal to the thermo valve and it closes the valve stopping flow to the cylinder. This is why you must leave the by-pass open (black lever valve) to allow circulation to continue, with some small circulation your boiler will continue to run until it reaches set temp and then turn its self off.

brettmirl

Thanks items. Yes the cylinder is new and the gas boiler is only a few months old too. It was the same guy that installed both.

The plumber is due back next week. I think he is going to test for leaks. He said something about taking a tap off the pipes. He also said the non-return vavle might be faulty. Not sure if that would make a difference or not.

The brown water issue has been going on for about 2/3 months now. Like I said earlier in the thread, it all kicked off one day after the mains was cut to the whole town. Thought it was just some dirty mains water going through the system after the water was restored, but it never went away.

The water from the hot tap does run clear if I leave it run for about 30mins until all the hot water runs cold, but eventually it colours again. From the colour of the water, it does look like its mixing with rust or that brown water that comes out of rads.

Anyways, I'm really hoping to get it sorted before Christmas, cause it's getting to be a pain now!

JamesM

items wrote: »

Some of the advice here is way off the mark. Its hard to follow.

Two things worth mentioning, the flexi hose with the little black handle is a by-pass and should be open slightly. You have a heat control (thermo valve) on your cylinder flow, when cylinder is hot enough it shuts off circulation to the cylinder. The by-pass must always be open, if you happen to shut off the rads and turn on the boiler, you'll have no circulation. You'll damage pump at boiler or worse, blow up the boiler.

The red handle gate valve above the NRV(brass cylindrical fitting) is your heating filler, it must also remain open at all times.

A little bit dramatic, items. The red handled valve tops up the system and there is no problem leaving closed off for quite a long length of time, especially when trying to establish if there is a leak in the system.
We have already established that the braided hose is a bypass. In most systems, if all the rads are turned off, the water still bypasses them and will still circulate without any danger to the boiler. If the closing of any valve endangered the system, the valve should not be there.(As in the case of backboilers where there are no valves on the primary circuit).
Jim.

JamesM

Brettmirl, The water from rads and the heating system is often black, more than brown. If the pressure in the heating side of things is not dropping, then it is likely that the two systems are not linked. You could now open the red valve and see if the pressure is any different to when it was closed.
If we take it for a minute that the problem is not with the coil, but that the brown water is coming from somewhere else, can you establish where all the pipes on the right hand side are going to or coming from - could there be anything else in the water system that could be causing the problem.
Jim.

ART6

brettmirl wrote: »

Hi ART6. Am in a typical 3 bed semi-d. The boiler is on the ground floor (wall mounted), the hot water cylinder is upstairs, and the water tank is in the attic.

The gauge reading on the boiler...there are two scales on it; one reads 0 to 4 and the other in red goes 0 to 60.

When the heating is off the needle is at zero. When I turn boiler, it immediately jumps to just below 1 (or 10 on the other scale) and when the heating reaches its top temp, the needles is at 1.5 (or 20).

After the boiler turns off, the needles slowly drops back to zero.

The boiler is a Sirrus Radiant RS20E.

OK so. If the boiler pressure is dropping to zero with the boiler off, then two points -- Given the position of your cylinder in relation to the boiler, I wouldn't expect the pressure gauge to show much less than 4.5 (psi) on the red scale with the boiler off since that is the pressure that 10 ft of water in the pipes would create. If it drops to zero then that suggests to me that the expansion vessel (the red thingy like a squashed football in the boiler casing) has run out of air and needs to be pumped up using a foot pump or something connected to the valve like a car tyre valve on top of it.

If it rises to 20 psi when the boiler gets up to temperature than there can't be a coil leak. Assuming that water level in the attic tank is (say) 12 ft above the coil, then the water head pressure would be around 5 psi and the boiler would not be able to exceed that as the extra pressure would simply bleed off through the leak.

brettmirl wrote: »

Pipe #4 didn't get hot immediately like the pipes I marked did once the boiler came on.

If, as JamesM and I have concluded, pipe 4 is the boiler return, then it will gradually get hotter as the cylinder temperature rises. It's only pipe 3 that will heat up to full temperature immediately. So that is all normal.

JamesM wrote: »

Brettmirl, The water from rads and the heating system is often black, more than brown. If the pressure in the heating side of things is not dropping, then it is likely that the two systems are not linked. You could now open the red valve and see if the pressure is any different to when it was closed.
If we take it for a minute that the problem is not with the coil, but that the brown water is coming from somewhere else, can you establish where all the pipes on the right hand side are going to or coming from - could there be anything else in the water system that could be causing the problem.
Jim.

I agree. Only thing I would say is that I have known small amounts of boiler circuit water to get into expansion tanks, and although in quantity it is almost black, when diluted it does tend towards brown. In any case, if the boiler pressure is rising to 20 psi then there can't be a cross over into the tap water circuit as JamesM says and for the reasons I said above. So the discolouration must be coming from somewhere else.

And incidentally, even if you could close off both the radiators and the boiler circuit completely you still can't damage or blow up the boiler as its relief valve would simply open and blow off the pressure, generally through a pipe out through your wall.

items

JamesM wrote: »

A little bit dramatic, items. The red handled valve tops up the system and there is no problem leaving closed off for quite a long length of time, especially when trying to establish if there is a leak in the system.
We have already established that the braided hose is a bypass. In most systems, if all the rads are turned off, the water still bypasses them and will still circulate without any danger to the boiler. If the closing of any valve endangered the system, the valve should not be there.(As in the case of backboilers where there are no valves on the primary circuit).
Jim.

Heating filler should be left open when finished working with system, if its left closed eventually the heating system will be starved of water supply leading to rads with air in them.

Who ever plumbed the house decided to use a flexi for by-pass out of pure laziness. The by-pass valve should have its head removed after its opened slightly. same goes for the valve on the coil. Just because its got a head on it, doesn't mean you can turn it on and off.

Your saying "in most systems" I am talking about the system in this thread, the way the system here is set up, the by-pass must be left open. If the red lever handle (summer valve) is closed along with the by-pass valve the system has no circulation.

No dramatics here just advice from a qualified plumber with 15 years experience.

yoshytoshy

items wrote: »

Heating filler should be left open when finished working with system, if its left closed eventually the heating system will be starved of water supply leading to rads with air in them.

Who ever plumbed the house decided to use a flexi for by-pass out of pure laziness. The by-pass valve should have its head removed after its opened slightly. same goes for the valve on the coil. Just because its got a head on it, doesn't mean you can turn it on and off.

Your saying "in most systems" I am talking about the system in this thread, the way the system here is set up, the by-pass must be left open. If the red lever handle (summer valve) is closed along with the by-pass valve the system has no circulation.

No dramatics here just advice from a qualified plumber with 15 years experience.

Items ,your not the only qualified person that is on the site. And not all filler valves need to be left open.

I specifically don't leave valves on ,so I know I don't have any leaks on systems.

items

ART6 wrote: »

OK so. If the boiler pressure is dropping to zero with the boiler off, then two points -- Given the position of your cylinder in relation to the boiler, I wouldn't expect the pressure gauge to show much less than 4.5 (psi) on the red scale with the boiler off since that is the pressure that 10 ft of water in the pipes would create. If it drops to zero then that suggests to me that the expansion vessel (the red thingy like a squashed football in the boiler casing) has run out of air and needs to be pumped up using a foot pump or something connected to the valve like a car tyre valve on top of it.

If it rises to 20 psi when the boiler gets up to temperature than there can't be a coil leak. Assuming that water level in the attic tank is (say) 12 ft above the coil, then the water head pressure would be around 5 psi and the boiler would not be able to exceed that as the extra pressure would simply bleed off through the leak.



If, as JamesM and I have concluded, pipe 4 is the boiler return, then it will gradually get hotter as the cylinder temperature rises. It's only pipe 3 that will heat up to full temperature immediately. So that is all normal.



I agree. Only thing I would say is that I have known small amounts of boiler circuit water to get into expansion tanks, and although in quantity it is almost black, when diluted it does tend towards brown. In any case, if the boiler pressure is rising to 20 psi then there can't be a cross over into the tap water circuit as JamesM says and for the reasons I said above. So the discolouration must be coming from somewhere else.

And incidentally, even if you could close off both the radiators and the boiler circuit completely you still can't damage or blow up the boiler as its relief valve would simply open and blow off the pressure, generally through a pipe out through your wall.

Hope you have a few quid to cover further damages. If you run the boiler with no circulation a few problems on top of the problem you have could arise. Boiler running with no circulation could lead to blown pump motor, blown high limit stat, blown diaphragm in expansion vessel, seating on safety valve damage, scalding of the person walking past the boiler safety, thats if you are lucky enough to have it even piped outside.

If your interested in solving the problem carry on but turn the boiler stat to its lowest setting while working things out and leave the by-pass open slightly, once its left open you can turn on and off any other valves until your hearts content.

items

yoshytoshy wrote: »

Items ,your not the only qualified person that is on the site. And not all filler valves need to be left open.

I specifically don't leave valves on ,so I know I don't have any leaks on systems.

Filler left open and a gauge for checking pressure (other than boiler) is best should you be worried about leaks. A system installed correctly and pressure tested leaves no leaks to worry about.

A boiler filler valve should be left open, end of. Their should be no reason not to leave it open, if leaving it open causes a problem then their is a problem with the heating system.

yoshytoshy

Items ,is there any harm in topping up a heating system when it's hot ?

items

yoshytoshy wrote: »

Items ,is there any harm in topping up a heating system when it's hot ?

A dose of cold water being introduced close to a roasting hot boiler could cause problems. If the cold water is being introduced to flow and return pipe work in hot press etc their is no real concerns.

Any maintenance to a heating system should be done at cold temperature, normally when you top up a system its down to venting out air etc, again makes sense the colder the better.

brettmirl

Hi guys. Am away for the weekend. Water was still the same when I left earlier. I opened the red valve before I left.

Will be interesting to see what the water is like after "sitting" for two days!

Art6 will check the pressure again on Sun evening.

Thanks to you all again for the help and advice. I can see my boiler and pipework becoming a specialist subject on Mastermind at this stage!!!

yoshytoshy

OP, have you tried running off the water until it's clear then leaving it a day without any heat to see if it stays clear, if it's heat orientated you may find it's bacteria(asper DARTH MAUL) , i have come across brown water with cylinders that got worse the hotter they got, the installer had to put a cleaning solution into the cylinder to get rid of it, also is the immersion new or is it the same as the one out of the old cylinder and have you taken sample of your system water from different places to see if your heating water is dirty.

the boring bit........

yoshytoshy wrote: »

Items ,is there any harm in topping up a heating system when it's hot ?

No, without generalizing, topping up heating system pressure when it's hot will have no impact on a modern gas boiler, if refilling a boiler with cold water was a issue you wouldn't find filling loops incorporated in boiler pipework and manufactures would warn against it in their manuals.

Just to clarify in respect of filling heating systems, mains fed heating systems should have filling loops that are left shut and capped, the mains shouldn't be left on to a mains fed heating system, tank fed systems must have the filling point left open as most gas boilers have the low pressure switch cut out of the boiler to allow the boiler to fire on low pressure leaving it with no protection against loss of water, i know of no boiler manufacture that have designed a tank fed boiler that can have the cold feed isolated and cover it in their instruction manual, so they put in no safety devices for the potential lack of water, technically you can be outside IS813 with this system design as they are not fitted to manufactures instructions, running a boiler with no circulation in my experience wouldn't lead to a safety valve blowing but to the boiler stat or limit stat shutting down the boiler to protect the pump,expansion vessel etc.. from being damaged, i dare say the noise would stop a second attempt:D , Gary.

JamesM

Edit - Post deleated - I'm backing off - Gary and Art know a lot more about this than I do
Jim

No, i have just made more mistake:)

items

gary71 wrote: »

OP, have you tried running off the water until it's clear then leaving it a day without any heat to see if it stays clear, if it's heat orientated you may find it's bacteria(asper DARTH MAUL) , i have come across brown water with cylinders that got worse the hotter they got, the installer had to put a cleaning solution into the cylinder to get rid of it, also is the immersion new or is it the same as the one out of the old cylinder and have you taken sample of your system water from different places to see if your heating water is dirty.

the boring bit........



No, without generalizing, topping up heating system pressure when it's hot will have no impact on a modern gas boiler, if refilling a boiler with cold water was a issue you wouldn't find filling loops incorporated in boiler pipework and manufactures would warn against it in their manuals.

Just to clarify in respect of filling heating systems, mains fed heating systems should have filling loops that are left shut and capped, the mains shouldn't be left on to a mains fed heating system, tank fed systems must have the filling point left open as most gas boilers have the low pressure switch cut out of the boiler to allow the boiler to fire on low pressure leaving it with no protection against loss of water, i know of no boiler manufacture that have designed a tank fed boiler that can have the cold feed isolated and cover it in their instruction manual, so they put in no safety devices for the potential lack of water, technically you can be outside IS813 with this system design as they are not fitted to manufactures instructions, running a boiler with no circulation in my experience wouldn't lead to a safety valve blowing but to the boiler stat or limit stat shutting down the boiler to protect the pump,expansion vessel etc.. from being damaged, i dare say the noise would stop a second attempt:D , Gary.

Correct and right. Boilers which require over 1 bar pressure tend to be fed from mains, only in this case the supply must be turned off and disconnected . Having mains water connected to a heating supply permanently is not allowed, valves, non return valves and so on still allow bacteria to pass through, makes sense really as you don't want to be drinking heating water. As mentioned these boilers will lock out should boiler loose water, pressure drops below the required amount. Gas boilers with gravity supplies (attic tank) should be left with supply open to save future problems, their should be no reason to turn off supply, turning off supply is only avoiding any problem created by having supply on.

I've seen jobs, fresh new sites with boiler permanently connected to mains via a pressure regulating valve, no idea how Co Council water division allowed it or how Bord Gas gave the installation the all clear.

As for running a boiler with no circulation, I guess its each to their own, boilers are not designed to run with no circulation and the amount of safety protection varies depending on boiler model. A top spec boiler may sense no circulation and shut down before damage but not all boilers are top spec.

I've been on sites with apprentices during the house bashing times, boilers being run for first time. A few cases happened when boiler was not filled correctly, with no circulation the boiler quickly overheated and blew straight out safety. Safety pipe should terminate 4" above ground but in Ireland they all terminate where ever is most handy, normally at head height. Unlucky for the plasterer who was out patching up outside when the safety blew. Same site had a number of visits from boiler engineer to replace parts after the boilers failed to return from lockout, all work carried out under guarantee because of manufacturing faults, had the boilers not have locked out under no circulation, faults wound not have been found. After my experience I never leave boiler safety down to boiler controls as they too can fail.

JamesM

items wrote: »

A boiler filler valve should be left open, end of.

Two reasons why it's not "end of"
Many systems are filled from the domestic water tank in the attic. If the non return valve fails or leaks, the water from the heating system will get into the domestic water tank when the pressure builds. It can discolour the water and taste rather dodgy if you do your teeth in the bathroom :eek:.
With older boilers, it is a good idea to keep the filler valve closed because one day the boiler is going to burst and start leaking. This is like turning on a tap in the middle of the house and flooding the place. If the valve is closed, then only a certain amount of water will escape. I supose after 40 years, you experience more of these incidences than you would in a short 15 years :D:D
Jim.

yoshytoshy

gary71 wrote: »

No, without generalizing, topping up heating system pressure when it's hot will have no impact on a modern gas boiler, if refilling a boiler with cold water was a issue you wouldn't find filling loops incorporated in boiler pipework and manufactures would warn against it in their manuals.
, Gary.

Gary ,your forgetting about the expansion vessel. You can damage it if you fill a system when the vessel is fully expanded.

I was only asking items ,to see what he/she might say about the situation.

JamesM

brettmirl wrote: »

Hi guys. Am away for the weekend. Water was still the same when I left earlier. I opened the red valve before I left.

Will be interesting to see what the water is like after "sitting" for two days!

Art6 will check the pressure again on Sun evening.

Thanks to you all again for the help and advice. I can see my boiler and pipework becoming a specialist subject on Mastermind at this stage!!!

You go ahead and enjoy your weekend - we're having great fun here :D:D

JamesM

yoshytoshy wrote: »

Gary ,your forgetting about the expansion vessel. You can damage it if you fill a system when the vessel is fully expanded.

I was only asking items ,to see what he/she might say about the situation.

If you don't fill the system above 2 bar the expansion vessel should be OK.
Jim.