Why is my stove not *that* hot? 30 December 2022 at 3:32PM in LPG, heating oil, solid & other fuels 28 replies 911 views

Andrea15

I have my multifuel stovax 5 and for some reason, although it is OK, it is not that roasting. I need to fill it with coal (or wood) and still it is not THAT hot.
Compare it with a stove I had in an air B&B a few weeks back... that was incredible. It was SO HOT it was nearly unbearable. That was a Pioneer 400 (never heard of it, but from what I read it should be the best) and it was placed in the middle of the room, i.e. not within a fireplace alcove, unlike mine.
In my case I believe I use the vents correctly, but still...
Ah, I also positioned a fan right at the back and that does help.

Any pearls of wisdom are welcome.

Thanks a happy new year!

Reed_Richards

Possibilities:

1. Too much heat is going out the flue.
2. Your stove takes less fuel than the one in your Air B&B so produces less heat in any given time.  This could be just due to reduced capacity for fuel or it could be that a reduced air supply means that the fuel does not burn so quickly.  Either way the plus side is that you consume your fuel less quickly so if the stove keeps you warm then you are running it more economically. 

Andrea15

I don't think it is 2, because the other one was of a similar size, and even with little wood the difference in output was very noticeable.

How to overcome 1?

FreeBear

Andrea15 said:

I don't think it is 2, because the other one was of a similar size, and even with little wood the difference in output was very noticeable.

How to overcome 1?

Turn the air vent(s) down. You want a slow wafting flame rather than a raging inferno. Get yourself a flue thermometer and aim for a temperature in the range of 120-250°C (250-480°F).

mumf

All the above. Air flow is important. The red hot one in the room is not in a fireplace in chimney. It will affect the heat. Mine has a fan on top that warms - well - the far corner of the room. TBH a stove has to be played with to understand it’s life in that room. Make sense?

mmmmikey

....another thing to think about is the fuel. What were you burning in the AirBnB? Regular house coal is not generally recommended for stoves because it burns too hot and leaves tar in the flue.

Andrea15

Yes, I believe I do all of the above, but still... the outcome is a bit "meh".
I am not sure the thermometer is reliable enough, anyway it struggles to get above 130 °C (270 °F) which is supposed to indicate the start of the "ideal" temperature.
With coal the temperature hovers at best around said 130°C, to raise it I would have to add more, but there is already plenty as it is pretty much level with the guard.

Andrea15

mmmmikey said:

....another thing to think about is the fuel. What were you burning in the AirBnB? Regular house coal is not generally recommended for stoves because it burns too hot and leaves tar in the flue.

No, it was just logs (and very few of them).

Olly_J

Have you set the vents per the manual for the fuel type?

Andrea15

Yes, the vents are as per your picture.
This has been going for about an hour and a half. 
............

Effician

Andrea15 said:

Yes, the vents are as per your picture.
This has been going for about an hour and a half.

What weight of smokeless coal is in that firing ?

What species & moisture content was the wood being burned at the b&b ?.

Is yours a Defra ( smokeless zone ) spec stove?

I'm guessing you expect smokeless coal to have a much higher energy value than wood  when in reality well seasoned wood can get very close to calorific values weight wise with smokeless coal,  ie a quick weigh of a small piece of ~10% Mc ash roughly 8"x4"x4" is 1.75kg & will be around 8.5kWh of energy, 1.75 kg of basic smokeless will be somewhat similar kWh wise but will take a fair bit longer to burn.