Advice on Thermal Store

[tomchapman]

Hi,

My house currently has a very "standard" setup of a gas boiler feeding vented tank (in the bathroom) & radiators through a motorised valve. The tank feeds a tap in the kitchen, bathroom and a shower (pumped from cold & hot tanks).

The Gas boiler is on its last legs, and its flue terminates inside the new extension, so this has been switched off for ages now.

I've bought an Aga which is being referbished and will be installed within the next year. This has the facility to heat water.

I've also got an air source heat pump (5kw) to provide heating over this winter, aid the aga if it needs it, and provide hot water when the aga is off for servicing, or if we choose to turn it off in particularly hot weather.

Now for the question!

I was thinking of scrapping the current tank, getting an unvented cylinder so I can relocate the cylinder downstairs. The main reason for unvented was so I didnt have to use pumps for the shower and tap upstairs.

I'm looking to do as much of the work myself as possible. I've been told that a thermal store may be a better option as unvented cylinders need to be installed by someone qualified.

So ..

Thermal store, fed by the aga + air source heat pump, radiators fed from store, and coil in the top of the store to provde mains pressure hot water.

Anyone see anything wrong with this? or any other advice/ideas?

Thanks.

Tom

 

[JonasX]

Tom, there is a thread on thermal stores right now. Read it.

Thermal storage is by far the best for solid fuel and heat pump. Reconsider the ASHP as they are expensive to run.

A good idea. Thermal storage is the only way using this setup. I would do this:

1. Have a heat bank - which is a store with the DHW taken off an efficient plate heat exchanger. Better than the coil.

2. Have it stainless steel. They last far longer.

3. Have it vented - essential with solid fuel.

4. Have the CH loop off a coil in the store. Have this loop sealed and pressurized using a cheap sealed system kit. This prevents any sludge build up in the cylinder as the CH and store water are separated from each other.

5. Have a Wilo Smart pump on the CH with TRVs on all rads, eliminating a central electric wall stat.

6. Have overheat protection. This can be an extra rad, or Danfoss do a device that allows cold mains water into the store, via small coil when near boiling to cool it down. The mains water runs into a drain. This is protection that may never occur.

7. Have the AGA heat the store directly.

This will give the optimum system. I hope this helps.

 

[tomchapman]

Thanks for the helpfull reply.

I've had a read of a few posts regarding thermal stores, but I'll continue to read up on them.

Sounds like a vented thermal store is definatly the way to go.

 

[JonasX]

Thanks for the helpfull reply.

I've had a read of a few posts regarding thermal stores, but I'll continue to read up on them.

Sounds like a vented thermal store is definatly the way to go.

A unvented store from this month needs a certified installer and an annual service.

 

[DeltaT2]

Ah, I see Dr Drivel has been talking to himself all day again???!!! You'd think he'd get banned for multiple user names??!! Ach well I guess he's harmless, if he keeps taking his medication...............

 

[JonasX]

Ah, I see Dr Drivel has been talking to himself all day again???!!! You'd think he'd get banned for multiple user names??!! Ach well I guess he's harmless, if he keeps taking his medication...............

Tom take no notice of the cowboys on here. This Delta fellow is one.

 

[JonasX]

Tom, you will also know them when they turn up in van that looks like this...

 

[gaswizzard]

Ah, I see Dr Drivel has been talking to himself all day again???!!!

yep. , he must think we are stupid.

 

[tomchapman]

I'm confused now!

I take it the advice from JonasX was good yes?

Still reading up on Thermal Stores, but certantly looks the easiest way of getting the perfect setup.

Would everyone agree the best way to have it setup is with 2 coils + a heat plate, heat plate feeds DHW, higher coil feeds CH, lowest coil to ashp. Aga is direct into tank.

Thanks.

Tom

 

[flameport]

There will never be any chance of the persons using this forum agreeing on a thermal store being the best solution. Search old threads for why.

There is no perfect system - they all have problems and disadvantages. Including thermal stores.

 

[JonasX]

There will never be any chance of the persons using this forum agreeing on a thermal store being the best solution. Search old threads for why.

There is no perfect system - they all have problems and disadvantages. Including thermal stores.

Firstly, the Cowboys do not understand them. They get brainache when they think of them. Secondly, a thermal store is the best for Tom's setup.

 

[DeltaT2]

Tom, you will also know them when they turn up in van that looks like this...

I see the Chuck Wagon has arrived with the beans, kind of ironic, cause this thread is full of hot air & skid marks.

 

[JonasX]

I'm confused now!

I take it the advice from JonasX was good yes?

Still reading up on Thermal Stores, but certantly looks the easiest way of getting the perfect setup.

Tom, read the http://www.heatweb.com site. Some good explanations there.

 

[DeltaT2]

Did DPS go t.ts up then?? Not another SLUDGE BUCKET manufacturer going bust!!! Wonder why eh???!!..............

 

[JonasX]

That van suits you.

DPS were bought out.