Boiler does not turn on for hot water

robshak

matt_drummer said:

Qriz

Turn on just the hot water on the programmer with the heating off and open the valve at 1 manually as they did before.

I have done it already..and it did not start the boiler..so more likely the thermostat at hw tank? And you are right, there is another silver box next to the boiler feeding other pipe..

Does it need any sort of reset after I change it? Seems just some screws to take old one out and put new one in, of course while the mains is off..thinking may be I should try this myself..

You guys are absolutely amazing taking time out to sort me out, on a Saturday..so lots of kudos..

robshak

matt_drummer said:

robshak said:

OK, did all of above. The boiler kicked in. Hot water is feeding CH but not getting into hw tank. So had to manually flick switch at position 1. Then hot water went into tank and is ONLY coming out of tank at point 2.

The tap has mild warm water, not even sure if it is from the hw tank or the temperature outside..ha ha..

As soon as the programmer for CH turned off at controller, the boiler shut down.

located inside the boiler?

I am not sure if you know how the tank works, forgive me if I am telling you something you already know.

 The boiler does not heat the water in the tank directly.

The tank has a coil of pipe inside it and the hot water from the boiler flows around the coil of pipe inside the tank transferring heat to the water in the tank that ultimately comes out of your hot water taps.

It will take some time to heat the tank, it is not instant like the hot water supply from a combi boiler. I know you have a combi boiler but it is set up as a system boiler.

It does sound like your three way diverter valve is faulty. it is item 1 in your photograph.

That may not be the only problem though.

If your are confident and careful you can remove the motorised head from the valve and make sure that the valve itself is not stuck. 

Be careful though if you do this, there is live mains electricity here so ideally you should isolate the electrical supply.

A new motorised diverter valve head is a cheap and easy fix. If you need to replace the whole valve it is a bit more involved.

There are plenty of videos online to assist you.

Absolutely you are not teaching me to suck eggs..all this is new info for me, so thanks a lot..specially taking time out on a Saturday to reply..amazing lot!!!

If the diverter is at fault, think I'm going to call in expert as don't want to start fiddling with plumbing..but if the thermostat is at fault as QrizB thinks, I am thinking of changing it myself..anything I should be wary of, apart from electrocuting myself..

matt_drummer

robshak said:

matt_drummer said:

Qriz

Turn on just the hot water on the programmer with the heating off and open the valve at 1 manually as they did before.

I have done it already..and it did not start the boiler..so more likely the thermostat at hw tank?

Does it need any sort of reset after I change it? Seems just some screws to take old one out and put new one in, of course while the mains is off..thinking may be I should try this myself..

You guys are absolutely amazing taking time out to sort me out, on a Saturday..so lots of kudos..

I would give it a go, they are not very expensive and at least it will take one thing out of the equation.

You could get a multimeter and find the fault if you feel confident.

Something like this

https://www.amazon.co.uk/Beizkna-Multimeter-Continuity-Resistance-Electrical/dp/B07W3T2542/ref=asc_df_B07W3T2542/?tag=googshopuk-21&linkCode=df0&hvadid=375498143972&hvpos=&hvnetw=g&hvrand=4813491229366750147&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006826&hvtargid=pla-835155387577&psc=1&tag=&ref=&adgrpid=76297946145&hvpone=&hvptwo=&hvadid=375498143972&hvpos=&hvnetw=g&hvrand=4813491229366750147&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006826&hvtargid=pla-835155387577

matt_drummer

I just had a read through the instruction manual for your tank.

There is a reset button on the tank thermostat.

Have you looked at this?

robshak

matt_drummer said:

robshak said:

matt_drummer said:

Qriz

Turn on just the hot water on the programmer with the heating off and open the valve at 1 manually as they did before.

I have done it already..and it did not start the boiler..so more likely the thermostat at hw tank?

Does it need any sort of reset after I change it? Seems just some screws to take old one out and put new one in, of course while the mains is off..thinking may be I should try this myself..

You guys are absolutely amazing taking time out to sort me out, on a Saturday..so lots of kudos..

I would give it a go, they are not very expensive and at least it will take one thing out of the equation.

You could get a multimeter and find the fault if you feel confident.

Something like this

https://www.amazon.co.uk/Beizkna-Multimeter-Continuity-Resistance-Electrical/dp/B07W3T2542/ref=asc_df_B07W3T2542/?tag=googshopuk-21&linkCode=df0&hvadid=375498143972&hvpos=&hvnetw=g&hvrand=4813491229366750147&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006826&hvtargid=pla-835155387577&psc=1&tag=&ref=&adgrpid=76297946145&hvpone=&hvptwo=&hvadid=375498143972&hvpos=&hvnetw=g&hvrand=4813491229366750147&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006826&hvtargid=pla-835155387577

I have a multimeter but have only used it for continuity and 12v troubleshooting in my camper..something else to educate myself..on resistance etc 😄

robshak

matt_drummer said:

I just had a read through the instruction manual for your tank.

There is a reset button on the tank thermostat.

Have you looked at this?

Just pressed the reset button and unfortunately, nothing happened..now reading the manual myself..replacement thermostat is 60 quids..now dilemma whether to buy or not without being 100% sure if this is the culprit..hmm..but at least I am close, thanks to you all.

matt_drummer

robshak said:

I have a multimeter but have only used it for continuity and 12v troubleshooting in my camper..something else to educate myself..on resistance etc 😄

For this purpose you only need to test mains voltage to and from the thermostat to see if it is sending mains voltage on the terminal that asks the boiler to fire.

The manual for your boiler is quite good.

There is a fault finding flowchart for your problem.

You have two thermostats, a tank temperature and one on the immersion heater.

They both have reset buttons on them.

If they have got too hot they trip.

If you haven't already you could check that the thermostats haven't triggered the safety protection built into them.

matt_drummer

robshak said:

Just pressed the reset button and unfortunately, nothing happened..now reading the manual myself..and looking for the cylinder thermostat replacement

I think there are two.

There are two immersion heaters and they both have thermostats. One of them sends a signal to your boiler.

Do you know which one is which?

I would imagine it is the one in the middle of the tank, not the lowest one.

FreeBear

robshak said: If the diverter is at fault, think I'm going to call in expert as don't want to start fiddling with plumbing..

you appear to have an S plan system, so you don't have diverter valves, just regular zone valves - One less port, but the mechanics of operating is still the same.

As for fiddling with stuff - You should really be a Gas Safe registered engineer to remove the cover on the boiler. There is usually a seal around the casing panels that need to be checked as there is a (very small) risk of fumes leaking out. Interesting to note that there are only three pipes entering the boiler at the bottom - Two for the central heating, and one for gas. No sign of a DHW heat exchanger, so the boiler is certainly a heat only model.

robshak

FreeBear said:

robshak said: If the diverter is at fault, think I'm going to call in expert as don't want to start fiddling with plumbing..

you appear to have an S plan system, so you don't have diverter valves, just regular zone valves - One less port, but the mechanics of operating is still the same.

As for fiddling with stuff - You should really be a Gas Safe registered engineer to remove the cover on the boiler. There is usually a seal around the casing panels that need to be checked as there is a (very small) risk of fumes leaking out. Interesting to note that there are only three pipes entering the boiler at the bottom - Two for the central heating, and one for gas. No sign of a DHW heat exchanger, so the boiler is certainly a heat only model.

There was no seal, just a latch at the top and two screws at the bottom to take the front panel out..I know my limits ha ha.. and I am now beginning to understand it may not be a simple fix e,g. a wrong setting somewhere,as I anticipated..so may be this is where I rest..your suggestions have been really educational for me..thanks..