Advance TSDC 140 - drain heating system to move radiator

[[spokes]]

Hi everyone,

My house is fitted with an Advance TSDC 140 unvented cylinder. I need to move a radiator, and believe that is is necessary and best to drain the system to do so. I consider myself a competent DIYer, but know enough to stop and ask questions before doing something new. I wanted to ask the below of people who know more than I do!

1. With a slow, steady and methodical approach, is draining this system a DIY appropriate task?
2. If so, can anyone give me any pointers on the best approach to do it?
3. Also if so, any pointers on the best way to refill the system, with the appropriate inhibitors?

I hold my hands up and admit there's a lot to know here, so please don't assume prior knowledge!

With best regards,

[spokes]

 

[terryplumb]

The unvented cylinders water doesn't mix with central heating system water.
Is your central heating system sealed and pressurised ?
Do you have a ladder type towel rail on the central heating system ?

 

[[spokes]]

The unvented cylinders water doesn't mix with central heating system water.
Is your central heating system sealed and pressurised ?
Do you have a ladder type towel rail on the central heating system ?

Thanks for replying Terry.

I'm under the impression that although the potable water and central heating water don't mix, I would have to drain the CH water to move the rad. Is this correct?

I'm afraid I don't know if I have a sealed and pressurised CH system - what could I look for to determine this?

I don't have any towel rails on the system - the new item being fitted is a towel rail however.

 

[terryplumb]

Yes ,you are correct .The heating system needs draining before cutting into pipework / ammending pipework.

 

[[spokes]]

Yes ,you are correct .The heating system needs draining before cutting into pipework / ammending pipework.

Thanks Terry. Would you happen to know if there is a specific approach to doing this specific to unvented cylinder systems?

 

[ianmcd]

Thanks Terry. Would you happen to know if there is a specific approach to doing this specific to unvented cylinder systems?

The unvented cylinder doesnt need anything, there is a coil that runs inside the cylinder and this carries the same water that runs through the radiators, that will drain when you open the CH drain valve, you might need to bleed the coile though when re-filling, post some pics of the cylinder and pipework, there should be an air vent there

 

[terryplumb]

TSDC 140 is a thermal store jobby isn't it Ian ? Boiler water fills the cylinder at around 75c and mains cold water runs through a coil heat exchanger.
Or is there another variant ?

---

 

[old duffer]

Hi everyone,

My house is fitted with an Advance TSDC 140 unvented cylinder. I need to move a radiator, and believe that is is necessary and best to drain the system to do so. I consider myself a competent DIYer, but know enough to stop and ask questions before doing something new. I wanted to ask the below of people who know more than I do!

1. With a slow, steady and methodical approach, is draining this system a DIY appropriate task?
2. If so, can anyone give me any pointers on the best approach to do it?
3. Also if so, any pointers on the best way to refill the system, with the appropriate inhibitors?

I hold my hands up and admit there's a lot to know here, so please don't assume prior knowledge!

With best regards,

[spokes]

Plumbing is either getting water to flow through a pipe or stop it coming out of a pipe. Its a basic a thing as is possible to do for the DIYer.

Some tips:..
make sure that when you do work and drain down systems, you think about ways in which you can add valves that mean you don't have to drain down a big store tank each time. Make sure you have drain points that also vent to outside.... very little cost and will save time latter.

Inhibitors against what? this is simply a marketing scam to extract wealth from the uneducated. Keep the water in your system clean by draining it every year.

Remove radiators every few years and wash them through with a hose pipe. This is THE ONLY PLACE where rust is generated

Everything you ever need to do plumbing wise is available in very exact detail on youtube...

ps...the mention of inhibitors will probably bring out condemnation by the the molecular plumbers LOL

 

[ianmcd]

TSDC 140 is a thermal store jobby isn't it Ian ? Boiler water fills the cylinder at around 75c and mains cold water runs through a coil heat exchanger.
Or is there another variant ?

---

I stand corrected @terryplumb the TSDC 140 is indeed a thermal store , I was reading the OP saying he had an Unvented HW Cylinder, never seen the part about it being a Thermal store, and OP forget the post about no Inhibitor required you need lots of it if draining this system down

 

[[spokes]]

OK, here she is! I've tried to get a picture angle that shows the most.

I really do need to get this done, and I don't think I'll get a plumber in any time soon. To that end, my research so far leads me to think the following:

Step 1: Turn off all power to the CH system. All pumps are off, all valves are off. Importantly, make sure the flow from the F&E tank in the loft is off.
Step 2: Identify and open suitable vent to allow water from heating side of system to drain
Step 3: Open drain valve at lowest point in system (in this case, a drain valve for the radiator on the ground floor outside)
Step 4: Wait until water drains. As this system claims to contain ~140 litres of water plus the contents of the radiators, this could take a while
Step 5: Once flow has stopped, close all valves except F&E tank. Check pressure is absent at radiators, and then conduct necessary work
Step 6: Open F&E tank valve to refill system. Keep an eye on water level as it rises through system, opening and closing radiator vents as necessary to avoid air locks.

There must be more to it than this? What do you think? And also, I'm unsure of how to know that the system is completely full again?

Many thanks everyone.

 

[terryplumb]

Pretty much as above ,but manually latch open the zone valve. Ensure the immersion heater is electrically isolated as well as the rest of the system.
Upon refilling add inhibitor,bleed the pumps as well as radiators .
If your downstairs radiators pipes are dropped from above , some ground floor radiators may well remain full of water, which isn't an issue if you are only cutting into pipework at higher than ground floor level.

 

[[spokes]]

Many thanks Terry. Can I ask what you mean by manually latch open the zone valve please?

Do you mean I should manually secure the ballcock for the F&E tank?

 

[terryplumb]

No not the F&e. The zone valve is a metal looking box with an electric wire coming from it ,and it has a manual lever.