Radiators upstairs are hot when hot water is on only???

[ShyBoy]

Ok, 2 weeks ago, as part of our front room renovations, i removed two radiators and capped under the floorboard. I then re-filled the system but have held off putting the inhibitor stuff in as i wanted to make sure everything is working fine before i do and replace floorboards.

A few days later, my wife noticed that 3 radiators upstairs are getting hot even though the central heating is programmed to off. I have read a bit on here, as i am no expert at all when it comes to CH systems, and the number one cause sounds like a divertor Valve. The problem is that i looked everywhere in the boiler cupboard upstairs but i can see anything that might resemble one. However, i did find a red tap with a label on it that says Central Heating Valve, but i doubt that is it.

Can anyone shed anymore light on this please? I really want to put the floorboards down but cant until this is sorted.

don't know if the system is gravity fed, but i do know there is one pump next to the boiler downstairs.

Just in case this means anything, we also temporarily removed two radiators (just closed the valves on each side, drained and removed). These are still removed.

p.s House was build late 50's

 

[D_Hailsham]

3 radiators upstairs are getting hot even though the central heating is programmed to off. .... the number one cause sounds like a divertor Valve. I did find a red tap with a label on it that says Central Heating Valve, but i doubt that is it

Which boiler do you have - make/model?
There are two types of valves; they look like this:
View media item 800 View media item 801
Do you have a hot water cylinder?
How many tanks are there in your loft?

don't know if the system is gravity fed, but i do know there is one pump next to the boiler downstairs.

If you have a pump, then the CH is definitely not gravity, but the HW may be. Depends on answers to the earlier questions.

boiler cupboard upstairs
pump next to the boiler downstairs

Do you have two boilers or don't you know where your boiler is?

 

[ShyBoy]

Thanks for the reply D_Hailsham.

The bolier is an "Ideal Mexico Super 2"

Cant find either valves in the cupboard upstairs that houses the hot water tank

In the loft we have a large cold water tank and a smaller central heating tank.

Sorry for the confusion. We have the boiler downstairs with the pump, and upstairs, we have the hot water tank (cylinder as you call it i think?).

With our system, you can either have Central Heating + Hot water OR Hot water only. We cant hace Central Heating only.

Just to be clear, can you confirm that it is impossible for this to be caused by simply removing two radiators and capping them? (keeping in mind that for now, two further radiators are closed off temporarily?)

 

[doitall]

The system has gravity hot water.

It is possible to install the system too good, same as the old gravity heating systems, anyway because all the pies have a perfect fall nice and straight etc, the heating will gravitate in the hot water only mode.

That valve that say heating is to stop it. so turn it off in the summer

 

[D_Hailsham]

The bolier is an "Ideal Mexico Super 2"

Cant find either valves in the cupboard upstairs that houses the hot water tank

If you have a pump and no valves, you probably have a pumped CH, gravity Hot Water system.
How many water pipes are connected to the boiler.?
Is the pump in the circuit to the HW cylinder or just the CH circuit?

With our system, you can either have Central Heating + Hot water OR Hot water only. We cant have Central Heating only.

That points to a gravity HW pumped CH system. One of the problems with this type of system is that you can get water flowing though the CH system when it is on HW only. One cure is to put an anti-gravity valve in the circuit.

Do you control the temperature of your Hot Water by the boiler thermostat? If so you should consider a cylinder thermostat and a motorized valve or two.

More answers please.

 

[steved101]

I would say an anti-gravity valve on the heating circuit (only opens under pump pressure) and a tapstat around the hot water cylinder or as mentioned a cylinder stat and a motorised valve (2 port)

 

[doitall]

Or

i did find a red tap with a label on it that says Central Heating Valve, but i doubt that is it.

The SB could turn the valve off when he doesn't want heating.

 

[ShyBoy]

The bolier is an "Ideal Mexico Super 2"

Cant find either valves in the cupboard upstairs that houses the hot water tank

If you have a pump and no valves, you probably have a pumped CH, gravity Hot Water system.
How many water pipes are connected to the boiler.?
Is the pump in the circuit to the HW cylinder or just the CH circuit?

With our system, you can either have Central Heating + Hot water OR Hot water only. We cant have Central Heating only.

That points to a gravity HW pumped CH system. One of the problems with this type of system is that you can get water flowing though the CH system when it is on HW only. One cure is to put an anti-gravity valve in the circuit.

Do you control the temperature of your Hot Water by the boiler thermostat? If so you should consider a cylinder thermostat and a motorized valve or two.

More answers please.

1. Two pipes coming out from the boiler. Only one has the pump attached. So i think your guess at gravity HW and pumped CH is correct.

If this is a 'normal' thing then thats fine. Just wanted to really make sure that i can start laying the floorboards and new wooden floor down. I was realy worried of doing that in case ill have to lift it all up again later if it was something to do with the removed radiators. (could not think how, but thought ill double check with you experts)

Could it be that now the system effectivly has 4 less radiators, it somehow overflows a bit too easily? It never used to happen which is what made me think the removal of the radiators had something to do with it in the first place.

 

[ShyBoy]

bump.