gravity to y plan

[halfax]

i have a gravity hot water system on my boiler. ( on the boiler there is a flow and return for the hot gravity . then a flow and return for the heating which is pumped.)
the hot water (gravity)is constantly getting air locked and stops working . the cylinder is on the third floor of the house.
is it possible to change to a y plan with zone valves, and pump.
there is no electric in the room where the cylinder is.
would it be possible to fit the zone valves and pump on the ground floor where the boiler is?
also the expansion pipe is on the flow ( on the flow gravity hot) as it goes into the cylinder .
would i have to move this if the pump was downstairs coming of the boiler

 

[EliteHeat]

You can fit a wireless cylinder stat in the airing cupboard and place the receiver wherever the zone valve is to be located. The range from the transmitter is about 30 metres for the Danfos one.

You must of course never allow the open vent to become closed under any circumstances ever, at all.

 

[cowley]

You can fit a wireless cylinder stat in the airing cupboard and place the receiver wherever the zone valve is to be located. The range from the transmitter is about 30 metres for the Danfos one.

You must of course never allow the open vent to become closed under any circumstances ever, at all.

Not as easy as that, quite a lot of pipework alterations required.

 

[halfax]

first thanks for taking time to reply
so it is not possible to have the zone valves on the ground floor?
i was hoping to use the existing flow and return ( the old hot water gravity) and connect them to the heating flow and return on the ground floor.
so there is a lot of pipe wor involved?

 

[GasMan1965]

There is a lot of work involved and without seeing the set up you have now it would be easy to get it wrong !!

 

[cowley]

On old gravity fed hot water systems the open vent is taken from the flow pipe to the cylinder and the cold feed/expansion pipe is taken from the return pipe to the cylinder.
If you connect the gravity flow and returns to the pumped heating ones as you are suggesting, the open vent and cold feed pipes will be in the wrong position and will give you problems with pumping over etc.
You would need to bring the open vent and cold feed pipes down to boiler position, or move pump and fit motorised valve at cylinder position and start your heating circuit from there either way lots of pipework.

 

[halfax]

if i bring the the cold feed down and the vent pipe to the boiler could i then put my zone valves near the boiler?
they are both in 15mm with it been a longer run should i increase the pipe size?
if it is a lot of pipe work it would be worth it in the long run would it . ( as all modern boiler are two pipe? i do not want a combi)

 

[halfax]

would the cold feed and vent have to be before the pump and would it be ok to use plastic barrier pipe

 

[cowley]

Yes you could fit motorised valve down at boiler.
The cold feed/expansion pipe would be okay in 15mm but the open vent pipe would need to be 22mm.
Can you post name/make of boiler and pic's of boiler and cylinder areas.

 

[halfax]

the boiler is a gloworm hideaway 80.
the existing vent pipe is 15mm would it be wise to change that now?
thanks again for your help.
the cylinder is in a room without a radiator that is another reason i want to use existing pipework on lower floor.
so it would only be a matter of running two pipes down the side of the existing hot water gravity it is three floors but very excessible

 

[cowley]

What size is the existing gravity flow & return pipes?.
Can you post pic's as requested?.

 

[halfax]

the feed (15mm) goes on the return
the expansion ( 22mm) on the flow before the pump.
an i right?
or can they both go on the return?

 

[halfax]

sorry jumping the gun.
the existing flow and returns are 22mm
sorry do not have a camera

 

[cowley]

The feed goes on return the open vent goes on the flow before pump yes.
But you are confusing the expansion, the cold feed pipe is also the expansion pipe, the open vent is what it says.

 

[halfax]

so the pipe from the small tank which i always thought was just a cold feed for the central heating system is also an expansion pipe.