Hot water not as hot as it was!

[Beowulf]

My system is as follows. Natural gas heating. Two bedroom house with three rads upstairs and three downstairs. I have a hot water tank in the bathroom. My Honeywell controller has the usual seperate settings for heating and hot water. Last year I didn't have to put the hot water on at all. I found that with the heating on the water was usually hot enough for anything I wanted. This year that doesn't seem to be the case and I'm having to put the hot water on as well. Nothing has changed since last year. I had a cold rad in the spare bedroom but that was easilly fixed by taking the top of the rad mounted thermostatic valve and easing the valve up and down with a pair of pliers. Gave it a squirt of WD40 and it hasn't stuck again. After doing that I balanced the system and the heating is working okay. With regard to the hot water side of things am I missing something there? I just can't understand why it was always hot last year and this year it isn't.

One seperate question. I read somewhere that the radiater in the room where the thermostatic control is fitted should'nt have a thermostatic valve fitted. Is that right? My thermostatic control is in the hallway just inside the front door and there is a rad in the hallway fitted with a thermostatic valve. Is there a particular way this valve should be set? Cheers

 

[Mike Jackson]

There is or was something very wrong with your system if the hot water was getting hot when only heating was selected. Are you sure the immersion heater hadn't been accidently turned on? As for the TRV where the stat is, turn it to maximum or remove the head completely.

 

[diamondgas]

Do you know the design of your system? Is is gravity hot water or pumped? Is it 'y' or 's'plan? That is does it have an electronic control valve or valves attached? More info on what you have installed will better help us give you advise

 

[midge]

Maybe something as simple as air needing releasing from the high point near the cylinder?

 

[Beowulf]

No the immersion definetely wasn't turned on, in fact it has never been used as I have it switched off. I had only moved into this house ans assumed this was normal as I had been on economy 7 before this! Re TRV thanks for that.

 

[Beowulf]

Well there is a large green valve in the hotpress with the name 'Wilo' on it and wires leading to it so I assume that is an elkectronic control valve. I don't think there is any pump so I assume therefore it's gravity.

 

[tipintim]

Post a photo. Wilo is normally the pump, never seen any controls with wilo.

 

[Beowulf]

Heres a photo. I thought I had posted it already but it mustn't have worked.

 

[Mike Jackson]

That's a pump. A wider view showing all of the controls would help.

 

[Beowulf]

Is this okay?

 

[MRDrip]

Do you have a unit with two or three pipes and electric cable going to it ?

 

[Beowulf]

No. What you see in the photo is it apart from the hot water cylinder and some more piping.

 

[diamondgas]

You see all them wires coming out of the box on the wall? Trace their path and I think you'll find a valve on the end of one of them or follow the pipe down from the pump, that'll most likely enter a valve or two

 

[Beowulf]

Sorry my mistake. They were behind the towels!!!

 

[MRDrip]

I would think the one on the left turning the hot water on or off could have a fault poss ?

Can you find a thermostat on the cylinder ? make sure that's working

 

[Beowulf]

Funny you should mention the thermostat on the cylinder as I had forgotten about it. There was a guy here about 4 months ago putting in some extra loft insulation under this energy saving scheme. Anyway one of the other things he did was to fit a new jacket on the cylinder. Don't know why as I had a practically new one on it at the time. Anyway I just checked and the thermostat was turned sideways and not in contact with the cylinder and was just sort of stuck between a join in the jacket. I have secured it properly to the cylinder now. Not sure what it should be set at though as at the moment it's set at 55. Could the fact that he had dislodged it from the cylinder have caused a problem?

 

[diamondgas]

Not a likely cause but may have dislodged a wire in the thermostat. More likely that the actuator on the valve to the hot water is faulty. There's a few electrical tests that should be done before replacing that though and checks to make sure the valve isn't seized

There should be a manual leaver you can pull across and lock into place temporarily ... check the bottom of the valve for a protruding 'paddle' thing!!

 

[Beowulf]

Thanks I'll have a look for that.

 

[Pipes Plumbing]

Excuse me if I've misread the first post, but to me it sounds like it's working correctly now and was in fault before.

With the S plan system you have, you shouldn't get the water heating without the DHW side switched on. The motorised valve should spring closed and stop the flow from the boiler going to the coil in the cylinder to heat the water.
Only when you switch on the HW side of the timer should you get any heat into the water in the cylinder.
I wonder of the DHW valve had previously been locked to manual or stuck open and is now working as intended???

With each side of the system zoned independantly you will be getting higher efficiencies and managing the temp of the water in the cylinder better, especially now you've put the stat back in the right place.

 

[Beowulf]

I think you are probably right. I only moved into this house just over a year ago and it was working in the way described when I moved in, so I guess the way it is working now is the way it should have been working from the beginning. I guess I was under the impression that no matter which was on, hot water or heating, the water in the hot cylinder would be heated with the only difference being that with heating on it would also activate the pump to distribute the water around the radiators.

 

[diamondgas]

Excuse me if I've misread the first post, but to me it sounds like it's working correctly now and was in fault before.

.

Nope I missread the first post Pipes Plumbing & have lead Beowulf down the wrong path ... many appologies Re-reading the first post and you are right it is now working correctly and wasn't before :dunce2:

 

[Beowulf]

Many thanks although to be honest I preferred it when I had both without having to remember to put the water on!