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steve1

Guys, As title suggests the reset light comes on from time to time on the front of the boiler, seems to be random, but what I have noticed is that if the room therm. is at 15 it will more than likely bring the reset light on.
Just need some pointers as to what this might be caused by.
Also, and not sure if it's related, the hot water seems to take ages to get hot at various outlets around the house, you have to adjust the flow to get it hot quickly, and as for the bath, well that's just a joke.
Thanx.
 
Assuming this is an external oil fired boiler, they're a real pain!

To help with the hot water flow, you can remove the flow switch and take the silly plastic restrictor thing out which will help a huge amount. It's not an easy job though and will take a lot longer than five minutes.

Also it's worthwhile checking that the water pressure going into the boiler is less than 2 bar or else you'll end up with the boiler fighting and creating leak problems in the future.

The heating side ... is the CH dial turned up and is there a programmer in the room? If this is the situation, it's often wired up to accept settings from the programmer so you need to turn the CH dial to off.

The logic is a bit like Windows. To turn off the computer you have to click start.

Hope this helps!
 
Thanx,
The boiler in an internal oil fired unit, I will check the water pressure, the thermostat is just an ordinary thumb wheel type.
This restrictor you speak about, where can i find this on the boiler.
Another question, the pressure guage on the boiler, what should this be set at, and when should it be set, (ie. when the boiler is idling), have noticed sometimes that it drops right off when the boiler is just sitting doing nothing,( when the heating is turned off).
 
I'll take the easy one first. The pressure should be around 1.25 bar when it's firing. If it drops to say 0.5 bar when idle then moves up to 1.25 bar when firing I wouldn't worry too much. If the boiler's firing at less than 1 bar then you'll have your water problems described earlier so you'll have to put more water in the system via the filling loop.

Have you a programmer in the house that you can - err - programme(!) to tell the system when to turn the heating and hot water on? And have you a room thermostat as well? If you have, these might be wired so they take priority over the boiler's own thermostat. If so, you need to turn the boiler's thermostat to zero and let the room thermostat and programmer take over.

Obviously, if turning the boiler thermostat to zero produces no heat whatsoever, then it's a different problem. Or if the boiler thermostat is on maximum, it's probably worth turning it down a little.

The restrictor is a different issue altogether. Inside the boiler there are loads of pipes. You'll need the manual and find the flow switch. Having isolated the inlet, you need to remove the flow switch (which is not easy!) and take the restrictor out.

The restrictor sits inside the inlet pipe under the flow switch. If you're unsure about this I'd get a plumber/heating engineer in as you could end up with a good flood or being unable to stop it leaking when you re-assemble the pipework. And while they're there, they'll probably be able to sort your heating out as well!

And if you get someone in, don't be too surprised if they suggest a different boiler rather than spending lots of money on this one!!
 
Hot water issue first: Warmflow oil combi? Is there a restrictor, not sure. I thought the flow switch in these was a paddle type like the worcesters. Leave it alone. There is a non return valve but it has to be there.

You will find that combi hot water performance varies through the year. At the moment, the water coming out of the ground may only be 4 or 5 degrees, so for the boiler to heat this instantaneously requires a blistering amount of available energy.....and although these combis have a well sized heat store, which is kept very hot indeed, the plate heat exchanger is frustratingly small.

Also, flow rate. Open a big bath tap which offers little in the way of hydraulic resistance and as much water as possible is rushing through the small heat exchanger (silvery box with 4 pipes attached to it) so it struggles to transfer the energy.

Do one of two things........ dont open the taps as far, or if there is an isolating valve of some manner on the cold water going in to the boiler, shut it off a little and see hot the hot water temp gradually improves. You sacrifice a bit of flow rate for improved temp gain.

General: It's unlikely you need a new boiler, just because this one is tripping out on the high limit stat. A vial type high limit stat and the relay it attaches to is about ÂŁ20.

It is likely that the other stat (vial type) in the top of the boiler is knackered, so not shutting the boiler down in a timely manner so the boiler temp is getting to high and the high limit stat is shutting things off to maintain safety.

Again, ÂŁ20 for a vial type and relay. Both of these are rudimentary repairs. Ring warmflow, however old the boiler is and they will put you in touch with a local warmflow approved engineer.

Wiring: If it is an external time clock it could be wired incorrectly but this would not affect the stats as the wiring in these goes to one terminal block. You can't over ride the internal stats.

Pressure; There is a low pressure cut out in these at 0.5 bar, so any cold pressure above that and you will have normal function.

If any of this helps, you're welcome. Any questions, feel free to come back to me.
 
Hi

Spent loads of time on a warmflow combi fitted in a utility room.

Not holding pressure. Remake every connection around the heat exchanger and mixer valve and use a fibre washer, ptfe and heldite/stag. Also around the expansion vessel, heat store draincock and replace the pressure relief valve. These are notorious sources of leaks which will cause your system to lose pressure. As its hot water you never see them but watch for powdery residue or green streaks. I also changed the filling loop and valve as it also leaked. Charge it overnight and leave cold to check for pressure drop.
Not supplying enough hot water. Check the circulating pump to the heat store is running and that the heat store is set at a high enough temp. This has a thermostat which can be changed to an adjustable one but you have to find the sweet spot between hot water and the hi limit occuring. Also when filling a bath run the CH for a short period as this seems to build up more heat in the boiler before supplying a load of DHW. On the bath taps I fitted service valves and partly closed them so that even with the taps on full they could only supply water at a set level. This is pain as the bath is slow to fill but then it is full of hot water. Oh, forgot to tell you to close the mixer valve fully so that there is no cold water mixing with the DHW.

Hope this helps you, come back with any questions. I hated this thing when I first looked at it but took my time and got it running well and the customer is happy with me.

Thanks

Joe
 
Hi,

Just joined, and have a warm flow burner as well. The H/L light has come on. and so have had no central heating over Christmas!! Trouble is I cant find the H/L reset button, and its not behind under ordinary thermostat dial! This is the first time this light has come on, and possibly due to a niece playin with the ordinary thermostat and leaving it on too high a temperature. Burner itself is please tell me where I might find the H/L reset button?? Thanks to anyone ....
 
Normally it's a pinkish red button around 10mm across. Plastic button, circular with a cross in it. This pops out when the thermostat is overheated/triggered (if you see what I mean - sorry - another liquid lunch!).

You simply push it back in ... and then curse next time it locks out again.
 
Hi,

Just joined, and have a warm flow burner as well. The H/L light has come on. and so have had no central heating over Christmas!! Trouble is I cant find the H/L reset button, and its not behind under ordinary thermostat dial! This is the first time this light has come on, and possibly due to a niece playin with the ordinary thermostat and leaving it on too high a temperature. Burner itself is please tell me where I might find the H/L reset button?? Thanks to anyone ....

On mine, you take the front panel off and the button is up the top on the left hand side.
 
On mine, you take the front panel off and the button is up the top on the left hand side.

Hi

I realise this form is a bit old but I had the same problem this Christmas and it helped! However my boiler is fairly old and did not have a red button with an X but it was located on the back of the thermostat. My boiler is a Warmflow M5 and if you take the top panel off you get access to the circuit housing box, behind this there was a bolt but its hollow, it leads to the back of the thermostat! If you put something plastic in and push you will feel a very small click, this reset's the thermostat!

Took me a while to figure out, had to remove the thermostat to figure this out but hope this helps someone next Christmas too!
 

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Hi

I realise this form is a bit old but I had the same problem this Christmas and it helped! However my boiler is fairly old and did not have a red button with an X but it was located on the back of the thermostat. My boiler is a Warmflow M5 and if you take the top panel off you get access to the circuit housing box, behind this there was a bolt but its hollow, it leads to the back of the thermostat! If you put something plastic in and push you will feel a very small click, this reset's the thermostat!

Took me a while to figure out, had to remove the thermostat to figure this out but hope this helps someone next Christmas too!

Hi Gaz and welcome to the forum.

Unusual first post in that you've given a solution and not asked a problem so thank you!
 
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