Is this normal??!!

Hello everyone,

This is my first post but I have found a lot of valuable advice on this forum so thank you! I hope you can help. I'm trying to learn about the heating system in the house.

There is a hot water cylinder in a cupboard, a water tank in the loft a boiler with a sunvic 207 select programmer which has separate CH and HW timers.

After a series of power cuts in the area, I've noticed the following:
1. the hot water is extremely hot and always hot. This is so even though the switch in the cupboard with the cylinder has been off for months and the boiler programmer for HW is set to off. There is no jacket on the cylinder, I plan to fit one a soon as I understand the system
2.The boiler randomly fires up during the day but especially when a hot water tap is turned on. Even though both the HW and CH is set to off. (I kept it on off for a week to find out whether it was doing this on it's own).
3. After a summer of being off, two of the downstairs radiators are cold. They are fed by the same pipe, but are separated by a wall. The worked on one occasion and haven't come on again so far. The water in the pipe is luke warm but the radiators are totally cold. (I have opened the valves on both ends)
4. The display on the CH and HW programmer has been playing up. It goes blank then comes on again then goes blank. If I set it for a time on CH, the moment it comes on it changes itself to constant and turns the HW to constant too even though it was set to off? The screen is always blank when it is in operation and the only way to turn the heating and HW off is to reset the programmer.

Can you please explain to me how these systems work and how they interact normally and if any of the above mentioned observations are normal? If I need to call a plumber in it would be good to have a basic understanding.

Thank you so much for your help, I really appreciate it

Sounds like the timer is faulty or wired wrong.
If both settings are off. Heating and hot water should be off and the boiler shouldn't fire at all.

Can you post one pic showing everything in the cupboard so we can see how it's all connected together? Close-ups of each part are not necessary.

PS it helps if the cupboard is empty

thank you so much for replies. I took some shots, but I'm not sure how to upload images? I have created an album what do I do next? Sorry, I'm new to this![/img]

RoseofSharon1 said:

thank you so much for replies. I took some shots, but I'm not sure how to upload images? I have created an album what do I do next? Sorry, I'm new to this![/img]

Click to expand...

Click on 'Upload Pictures' under the ad near the top of this page>Click 'Edit Album' on the right side>Click on 'Add New Images'>Click on 'Browse'>Open the pic you want>Press 'Browse' again and open another image if you want more than one>Finally click 'Upload Images'

Thank you!

I apologise for the lack of clarity in some of these shots!

I don't have permission to view the pics! Can you please change your settings.

Click Images (top of page)
Open the Album.
Click on Edit Album Info
Scroll down
Select Everyone or All Registered Users

Ooops, sorry! I've changed them now hope it works

The problem is almost certainly caused by this valve, which controls the flow of hot water from the boiler though the coil in the HW cylinder. The valve is opened by the stat on the side of the cylinder (your first pic) and an internal switch then turns the boiler on.

The valve is probably sticking open, so the switch is closed and the boiler lights.

D_Hailsham said:

The problem is almost certainly caused by this valve, which controls the flow of hot water from the boiler though the coil in the HW cylinder. The valve is opened by the stat on the side of the cylinder (your first pic) and an internal switch then turns the boiler on.

The valve is probably sticking open, so the switch is closed and the boiler lights.

Untitled

• D_Hailsham
• 12 Dec 2013
• 1

Click to expand...

Thank you D_Hailsham for this advice, I will look into it this afternoon and let you know how I get on

Umm, but the OP said this has been happening with the CH/HW off at the programmer. So there shouldn't be any power to the valve.

Given that the programmer display is playing up, I'd suspect some fault with that maybe?

OP did it use to work ok? And I'm wonderign about the switch - do you actually know for sure that this is supposed to isolate the whole CH/HW system? If so then it's even odder if it still works with that off.

There is a permanent live in both the two port valves, they dont need a feed from the programmer to work, if the microswitch sticks the boiler will fire and you would need to turn off the whole system to get it to stop.

Thank you so much for all the replies. If the valve is sticking open as D_Hailsham suggests, how can this be resolved? Will I have to switch the whole system off as Picasso suggests and if so how do I do this? Also how is the cylinder still working if the switch shown in the last photo has been off for months and not turned on at any point?

Do these things just work of their own accord?!

Yes, of course, Picasso is right, was having a bit of a brain fart there obviously

All the CH/HW system should be fed via a switch so that the whole thing can be isolated. That switch obviously isn't doing that. Assuming that it is connected up to system and seems supposed to do that- can't see from the photos, but I assume you can in real life, there are a few possibilities:

1. The switch is wired incorrectly - easy enough to check by undoing the faceplate and having a look inside (with the power off of course).

2. The switch is faulty and not switch off .

3. there is another supply for the system somewhere.

And thinking about it, a friend had a problem with their system that was down to a failed microswitch in the valve.

OP, are you familiar with the general principle of how the programmers, thermostats, valve work together to control the system. It will help with troubleshooting to understand that.