Intergas HRE 30/36 Thermal Store

[ben123d]

Hi,

I appear to have an issue with my Intergas boiler connected to my thermal store.

It is recommended to keep the thermal store (Gledhill TGH350) at 75c. I have the boiler set at 85c, but after taking the boiler flow temp earlier (before CH came on) at the boiler and at the thermal store, it is only registering 65c. Now taken another reading with CH on, and the flow temp is down to 58c.

The boiler is supposed to have an output of 30kw, and the CH has an output of 16kw (with all the rads totted up), so not sure why it's struggling.

Has anyone else had issues with the Intergas boiler flow temps on thermal stores?

 

[muggles]

Should be fine, but remember the flow temp won't be 85 all the time. There's a lot of water to heat! Are you saying that the boiler is switching off once it hits 65?

 

[ben123d]

Should be fine, but remember the flow temp won't be 85 all the time. There's a lot of water to heat! Are you saying that the boiler is switching off once it hits 65?

This morning, I tried setting the control thermostat to maximum on the TS, and running the boiler. The boiler fires and starts burning (hear the fan/burner, steam coming out of the flue!), ran for about 5 minutes, reached 68c and then powered down (fan/burner goes quiet, no steam out of the flue). Left it about another 5 mins, didn't turn back on.

The control stat on the TS (referenced above), should control when the boiler fires when it falls below the set temp on that stat. However, even with it set to max, the boiler is turning off for some reason. The boiler (on the boiler controls) is set to a temp of 85c, in effort to get the TS to the required 75c on the tank stat.

I am wondering on the Intergas HRE 30/36 when it is in 'heat only' mode for a TS, is it the DHW temp setting it is using for flow temp or the CH temp setting? You can still alter both in the boiler setting, although the light on the boiler control board indicates the CH is running as it's lighting the little radiator symbol.

 

[ben123d]

Should be fine, but remember the flow temp won't be 85 all the time. There's a lot of water to heat! Are you saying that the boiler is switching off once it hits 65?

Essentially, yes it keeps knocking off around the 65c mark.

Is there a reason why the boiler turn the burner and fan off (I.e. go to setting 1) when it hasn't reached the control stat temp (even when this is set to maximum 90c)? No other external sensors attached, just the control stat on the TS, which dictates when the boiler should fire.

 

[muggles]

Could be due to differential between flow & return temps. What are you using to measure the temperatures

 

[ben123d]

Could be due to differential between flow & return temps. What are you using to measure the temperatures

Using an IR thermometer, taking readings at boiler and TS end. I’ve double checked with a thermometer wedged between insulation and pipe, and the two readings aren’t that far apart.

The difference between flow and return is usually around 10c. Apologies if that’s not what you mean by differential. Some temps taken at the TS, which was set to maximum (90c) for the test

 

[benaround3]

I am actually thinking of getting a thermal store to run with my present Intergas Compact HRE 24 OV which was installed 3 years ago. We are in a house we are extending to 4 bedrooms and having replumbed. The plumber is waiting for me to decide. Without hijacking, any points to watch for welcome. As I understand it so far the problem isn't necessarily due to the boiler until a fault with TS thermostat is ruled out?.

 

[muggles]

I am actually thinking of getting a thermal store to run with my present Intergas Compact HRE 24 OV which was installed 3 years ago. We are in a house we are extending to 4 bedrooms and having replumbed. The plumber is waiting for me to decide. Without hijacking, any points to watch for welcome. As I understand it so far the problem isn't necessarily due to the boiler until a fault with TS thermostat is ruled out?.

Thermal stores are terrible for condensing boiler efficency. Get an unvented cylinder and run it on priority hot water

 

[ben123d]

I am actually thinking of getting a thermal store to run with my present Intergas Compact HRE 24 OV which was installed 3 years ago. We are in a house we are extending to 4 bedrooms and having replumbed. The plumber is waiting for me to decide. Without hijacking, any points to watch for welcome. As I understand it so far the problem isn't necessarily due to the boiler until a fault with TS thermostat is ruled out?.

worth having a read around on TS and the upsides and downsides. If you have a potential for solar PV / thermal, wood burning stoves etc, and want to input a lot of different heat sources, I think they are great.

TS control stat I think is ok, as the boiler really struggles when the CH turns on. For some reason, it just won’t get to the 80c set on the boiler, or anywhere near it. Resulting in warming rads and generally uncomfortable house in winter!

 

[Razor900]

Hold the spanner button and press + twice.

The display should read 'H'

See how hot the pipes get in the next 20 mins

 

[gasbanni]

Sounds like a controls issue the boiler can be wired up to replenish the cylinder at a rate different to the heating so that the store will heat up really fast.