Do I get rid of my Gledhill Thermal Store?

[ThermalStoreOrBust]

So I've got a bit of a conundrum. I've recently moved into a new house and have inherited a system which really isn't performing the way i'd like it too.

The system has a gledhill torrent thermal store which is roughly 11 years old. I've also got a Worcester Bosch Greenstar RI boiler with a magna clean fitted. Its an s plan system. When we first moved in we had a wood stove with a back boiler connected to the gledhill but had this removed.

I've got two issues and one is more critical than the other.

Issue 1 - A minor leak. So I've got a leak somewhere on the tank/thermal store. I don't know if its from a connection or the tank itself as its wrapped in a thick insulation jacket. All I know is that there the floor beneath the tank is damp and the leak is worse when the whole system is cold and has been powered off for a few days (had issues with the boiler which meant it had to be off for a few days which is how i found out about the leak)

I'm on the British Gas plan and had a gent over to fix the initial boiler problem and he subsequently spotted the leak. British Gas quoted to repair the cylinder at £2.5k. Since I was spending that sort of money I looked at quotes for a combi system which was interesting. I had AA, boiler plan uk, helplink.co.uk, eon and BG. They all quoted the same Worcster Bosch Combi apart from Eon and British Gas's combi guy (different from the person who quoted the repair) who refused to quote on ethical grounds because said that we'd be better off repairing what we have as its a superior system and a better fit for our house.

Its a 1930s house with 13 radiators and two bathrooms (electric showers). Allt he heating system is in the attic (boiler and thermal store)

So now i'm a bit stuck with the next step, I've reached out to gledhill about fixed fee repairs or replacements and am awaiting a response.

Issue 2 - This may or may not be related to the age of my system, the issues above or something separate completely at all but my radiators do not get hot. In my previous house a radiator on full blast would not be something I could touch without burning myself. In my new house the radiators at best get lukewarm, the heat isn't consistent through out the radiator either. There are cold spots. I've had one of the bigger radiators off the wall and completely cleaned it out so that clear water ran through it but that didn't seem to make a difference.

I know conventional thinking would point to a power flush to solve this but i'm conscious of throwing good money after bad if a replacement system is on the cards that would include either a chemical or power flush as part of it.

So that's it. I'm interested in general thoughts and ideas really. Should I be ripping off the insulation to identify a leak? Would a straight swap to a combi be best overall for simplifying the system. People talk about mains pressure hot water being a big selling point for the thermal store but i'd rather live in a hot house with a trickle of hot water than what I've got at the moment. Could I have both with a simple power flush and a repair? Do local plumbers typically have the expertise of thermal stores to carry out a repair or should i be looking at some of the bigger companies? I know there are probably some key details that I've missed so feel free to let me know if i need to clarify anything. I've included pictures for your enjoyment.

Thanks in advance for reading.

 

[durhamplumber]

get rid..having worked on several.they are universally awful.Imho!

 

[oilboffin]

X1 they are crap

 

[flameport]

If you want mains pressure hot water, get an unvented cylinder installed instead of the thermal store. Change at least one of the showers to a mixer at the same time.

If you really want a new boiler, and can live with the craptacular electric showers, then a combi would be the cheap and fairly nasty option.
However there is no point in replacing a working boiler - that in itself won't fix any of the other problems.

Flushing out the system would be a first step before any of that, and should be done regardless of which option is chosen.

I've reached out to gledhill about fixed fee repairs or replacements and am awaiting a response.

You will be waiting a very long time.

With no wood stove, the only semi-reason for the thermal store has gone.
When they leak, they are a total loss. Even when not leaking they have questionable benefits. Being made by Gledhill only makes it worse. It belongs in a skip.

In my previous house a radiator on full blast would not be something I could touch without burning myself.

Modern boilers operate at lower temperatures, so the radiators may be cooler than on an older system. Assuming they are correctly sized, installed, etc.
However lukewarm with cold spots is definitely not acceptable.

 

[ThermalStoreOrBust]

Thanks for the advice, so the consensus seems to be stick with a cylinder rather than a combi, but replace the thermal store with something newer. Anything I should be looking at superficially when getting a new cylinder?

Also is there any mileage in having a chemical flush rather than power flush?

 

[Ptuk]

If you are selling the old one please let me know. [email protected]

 

[MeldrewsMate]

If you change, go for a Heatrae Sadia Megaflow. You'll pay only a little more than for another brand, but they are market leaders and, if I judge correctly, you are more interested in getting a proper solution than saving a few quid.

First priority is to cure the leak. When removing the insulation bear in mind that you will have to replace it once finished, so think before you cut, and buy some wide gaffer tape. The main body of the heatstore is at low pressure, fed from the small tank above it. If you isolate the topping up water to this tank, then observe the small tank's water level, a leak will present itself as a drop in level OVER AN EXTENDED PERIOD of a week or month dependant on the magnitude of the leak. Remember, it's called a feed and EXPANSION tank for a reason, so when comparing levels do so when up to temperature to avoid error.

The hot water circuit is at mains pressure, a leak here will not cause the tank level to drop. There will be a preset mixing valve (mixing heated water with cold to give c.60C output temperature to the hot taps). Check this is working correctly.

Turning attention to the poor radiator temperature, I notice that your boiler thermostat is set quite low. You state you have an S-plan system, but this may not be the case. Typically a thermal store (like yours) needs very hot boiler water to perform adequately, so turn the boiler up to near maximum and re-assess. Then have the heating circulating pump inspected and cleaned, and the temperature of the heating flow pipe measured. If that's not hot there's no way your rads will be any hotter. Some thermal stores use a preset mixing valve to reduce flow temperatures. Check this operates correctly if fitted.
If the boiler was fitted to a dirty system, then the Magnaclean will only be partially effective. Hard deposits may be present in your rads, and the simple addition of a good chemical cleaner may reap benefits, though you will need to add extra chemical because of the extra water capacity of the thermal store - 13 rads + thermal store = 3 or 4 litres of (say) Sentinel x400 at about £15 a litre. If doing this check and clear the Magnaclean on a regular basis, the frequency determined by the amount of she-ite found in it.

Checking the tank level is well within the scope of DIY, and will enable you to give clear instruction/symptoms to any professional help you employ to do the other stuff, helping to keep those costs as low as possible. Adding x400 correctly is also DIY, as long as you know how to drain and refill the system, plus how to service the Magnaclean.

One final point. Do not combine finding the leak (my second paragraph) with any other work, including bleeding rads, as this will give changing tank levels and confuse the results.

Hope this helps.
MM

 

[durhamplumber]

get rid..having worked on several.they are universally awful.Imho!

Plus one for that

 

[ThermalStoreOrBust]

Got a local firm in to rip it out. No leak and better performance on the rads. Thanks for everyone's help.