Thermal stores and heat banks

[mike_s]

Been doing a lot of research on these this week and would like to have a discussion here.
Anybody have one or has fitted one of these?

I'm very intruiged and may be fitting one for a customer in a couple of months.
I prefer the sound of the heat bank arrangement with external plate heat exchanger and direct cylinder however there arn't many readilly made unless you pay around 1500 quid for a dps one it seems.

What is wrong with a diy heat bank? direct cylinder, plate heat exchanger, pump and flow switch, connected to an S or Y plan. Do I need to build in diffusers?

Also been looking at the Albion and gledhill direct thermal stores with coil but probably not where there are major hard water problems.
I prefer the sound of direct versions as re-heat times are quicker and less likely to lime up.

I will be speaking to manufacturers soon but I have a couple of questions.
Do I need 22mm cold main and if the water pressure is relitively low, but they have more than 1 bathroom, could it still be worth it over a combi which would not suffice?

Which models of thermal store/heat bank do you prefer and why?
Thanks, looking forward to replys.

 

[kimbo]

I have fitted a few thermal stores but I prefer unvented. Try Solar Panels - Photovoltaic Solar Panels & Solar Water Heating Panels they do a thermal store and they will be more than happy to advise you, they specialise in rnewables and I prefer to fit their solar systems because they are well priced and work well.

 

[ecowarm]

I have fitted Newark Copper Cylinder [DLMURL="http://www.newarkcoppercylinder.co.uk/cylinders/solar_thermal_store/"]Solar Thermal Store | Newark Copper Cylinders[/DLMURL] and also mcdonald eng. Thermal Store, Thermal Stores and Thermal Storage Hot Water Cylinders - THERMflow

Both very good and will make to your own spec.

I have also in the past made a themal store out of a second hand direct cylinder and a plate heat exchanger from a combi. downside over this arrangment is if you have a power cut you have no hot water even with a full tank of hot water.

The thermal stores with hot water from a coil still work with no electric.

Post above the link to Navitron, they use Newark copper cylinders

 

[mike_s]

🙄

I have fitted a few thermal stores but I prefer unvented. Try Solar Panels - Photovoltaic Solar Panels & Solar Water Heating Panels they do a thermal store and they will be more than happy to advise you, they specialise in rnewables and I prefer to fit their solar systems because they are well priced and work well.

Cheers had a look at that, will certainly consider them.
Can I ask why you prefer unvented? I see thermal stores as usually easier and quicker to install.
Unvented can provide better flow rates but thermal stores capeable of more pressure, up to 6-9 bar if the incoming main is good enough? As they are not restricted to 3.5 bar unlike unvented cylinders?

 

[kimbo]

Thermal stores have to be heated to a higher temperature ie 80deg whereas an unvented heats the water to the temp you want,also you have to be qualified to fit them as they could blow the side of a house out. It all depends on the circumstances, my latest installation will be a thermal store because the mains pressure is low.
Believe me you wouldnt want 6 - 9 bar pressure 3bar is plenty its the flow rate which is the most important. Flow and pressure are two different things. With some of the unvented cylinders you can buy different pressure reducing valves.

 

[gaspastemania]

Fitted many thermal stores and my advice avoid gledhill like the plague , completely unreliable after a couple years ,need constant refilling kettling issues blah blah blah , fitted an albion mains flow in replacement of gledhill recently and seemed a much better set up also look at telford cylinders as also fitted those and seem a steady set up.If you have no point of discharge then thermal store is an ideal replacement ,just to let you know still have to PRV the main.

 

[mike_s]

cheers good replys, yep heard too many bad things now about gledhill and their customer service so would be looking at an albion, navitron or telford. Still would prefer an external plate heat exchanger with no coil.
I Know 3.5 bars from an unvented is plenty and yes the flow is most important but thermal stores are often an easier conversion from a conventional open vented cylinder however they seem slightly more expensive than unvented cylinders.
I didn't realise about still having to prv the main, does it have to be 22mm also?

 

[mike_s]

infact, I will just tell you about my scenario. Customer owns 2 bathroom 2 storey converted bungalow. Incoming main isn't great, I'll measure it when they want a proper quote. Their hot water pressure is crap and virtually none existant upstairs as the tank isn't high enough and can't be higher. They have an electric shower but they often use both baths, they asked us for an estimate for a combi which we gave them but I don't think a combi is suitable here especially with 5 people living in the house using both bathrooms.
Was thinking about an unvented cylinder or thermal store. There is a y plan and pump in the airing cupboard which is in the middle of downstairs, I could run a pressure relief under the bathroom floor but a thermal store just seems easier and I think would result in better flow as the pressure isn't great?
I'm gsr but don't have my unvented ticket, I will be doing that very shortly so I admit I don't know the most about unvented either.

 

[desrob]

🙄
Cheers had a look at that, will certainly consider them.
Can I ask why you prefer unvented? I see thermal stores as usually easier and quicker to install.
Unvented can provide better flow rates but thermal stores capeable of more pressure, up to 6-9 bar if the incoming main is good enough? As they are not restricted to 3.5 bar unlike unvented cylinders?

why would you need pressure at 6-9bar.

 

[mike_s]

I'm not saying you do, just pointing out that they are capeable of greater pressures which may result in better performance from multiple showers than unvented? Maybe not better at filling baths but apparently thermal stores also work effectively down to 1.5 or 2 bar which I'm not sure if unvented would?

 

[mike_s]

Nobody else have experience with thermal stores?

 

[TTB]

I do but i only register to read post and pick up on all the problems installers have on the forum, hope you dont mind guys.
I have made thermalstores as well as all the other types of units for a living and know all the pros and cons against all systems and make.

Need to know more just email [email protected] we may be able to help and point you in the right direction.
There is the option of using a PAW heat exchanger unit supplied by Secon solar and the direct feed thermalstore.

Cheers TTB