How to find S or Y and the valve?

[truthfinder]

Hi,
Potterton Boiler in the garage. Open Vented I belive. [Loft has Expansion & Feed Cistern]. Above the boiler a pump connected to the return pipe.

Electricity supply to the boiler & its associated equipment is in complete isolation in the corridor. Fig 1.

In kitchen a Honeywell Timer. Timer has two choices- "Heating & Hot Water " or "Hot Water" See Fig 2.

In the hallway situated a Room Thermostat. See Fig 3.

Upstairs has hot water cylinder in the Airing cupboard. Just above the airing cupboard in the loft two cisterns-one the Feed cistern feed cold water by gravity into the hot water cylinder. Next to it in the loft situated the expansion cistern.

When ever the water alone is selected for heating, the radiator in the bathroom get heated too but not other house radiators. This bath room radiator is connected to the hot-water tank in the airing cupboard.

My question is
1. Is this system has S or Y plan?

2. When hot-water tank is heated alone by selecting a choice in the Honeywell control in the kitchen,[without the "central & water heating"] how does this happen? A valve bring about this control I suppose.

If it is a vale where would that valve be situated?

Is a valve mechanical one or electrically operated zone valves?

Electric Supply to the Boiler

• truthfinder
• 29 Oct 2012
• 1

Honeywell controller

• truthfinder
• 29 Oct 2012
• 1

Honeywell controller

• truthfinder
• 29 Oct 2012
• 1

Room Thermostat

• truthfinder
• 29 Oct 2012
• 1

 

[twgas]

Sounds although you have a gravity hot water/pumped central heating system.
If that is the case there would (probably)be no motorised valves.
Does the pump run when you select hot water only?
Is there a thermostat on the hot water tank?

 

[truthfinder]

Sounds although you have a gravity hot water/pumped central heating system.
If that is the case there would (probably)be no motorised valves.
Does the pump run when you select hot water only?
Is there a thermostat on the hot water tank?

Thank you for your prompt help.
Answer to your Q1 : Yes Pump runs when I select Hot water only

Answer to your Q2: No there is no thermostat on the hot water tank.

So that could I presume there is no motorised valves?
regards

 

[45yearsagasman]

Disregard the gas supply, how many water pipes come off your boiler. A pic of it would help.

 

[truthfinder]

Thank you Pete.

Disregard the gas supply, how many water pipes come off your boiler. A pic of it would help.

There are two water pipes come off the boiler.
Pic attached:

The Pipe connections

• truthfinder
• 29 Oct 2012
• 1

There are only two connecting pipes on the top of the boiler

The Pipe connections

• truthfinder
• 29 Oct 2012
• 1

There are only two connecting pipes on the top of the boiler

What do you feel?
Regards

 

[truthfinder]

I feel my system is " Fully Pumped Open Vented"

Reasoning is
1. I can see one pump outside [on top] of my boiler.
So the pump does the circulation for the DHW [primary] circulation & radiator circuits.

But then I am unable to figure out as to how when I choose on my Honeywell timer to "Hot Water only", the DHW [Primary circuit] selectively heated up without my radiators warming up? This is my quandary?

Honeywell controller

• truthfinder
• 29 Oct 2012
• 1

Any suggestion to help me with my confusion

 

[truthfinder]

I think the pipe connection to the boiler, from the fig below, is clear there is no hot/cold pipes connected proximity to the boiler after the pump except the main 28mm Flow & Return pipe.

The Pipe connections

• truthfinder
• 29 Oct 2012
• 1

There are only two connecting pipes on the top of the boiler

My pump is connected to the return pipe on the boiler which transmits the hot water by being pumped to DHW [Primary Circulation] as well as radiator circulation.

In a gravity fed hot water I should be able to see a return and a flow pipe from and to a DHW -Cylinder connected after the pump to the boiler. This I do not see.
The fig below:
http://www.diyhowto.co.uk/projects/open-vented-heating.htm

Now where is my "By-Pass valve"? This what I am unable to find? Will this be hiding under my celing? I would have though it should have access for any repairs??

Can any-one suggests anywhere to look for? [I have looked in-side the airing cupboard and do not find any such by the way.

Only one radiator in the house has this and this radiator directly connected to the DHW Cylinder. Could this be the ?By-Pass Valve?

A Honeywell valve on the Radiator

• truthfinder
• 29 Oct 2012
• 1

Only radiator in the house to have this attached to. This particular radiator is always hot when...

Regards[/url]

 

[dormermike]

Is your three port valve near the DHW cylinder? Have you looked there? Trace the pipes, etc

 

[Armo74]

Do you have any gate valves in the airing cupboard apart from the one connected to your cold feed from your CWSC feeding your hotwater cylinder?