Heating Water Temperature?

[cancunia]

Hi,

I wondered if there's a view on the best / optimum water temperature in a pellet stove? My MCZ stove can be set to operate between 130 - 175 deg F, but somehow lower settings seem to use more fuel. I guess that the number of radiators will have an effect but wondered if anyone has some kind of calculator or reckoner that can be used?

Thanks

 

[alternativeheat]

I don't have any calculator but can tell you that my oil boiler runs up around 190 deg F. And it cycles down to about 160 for a fire call. My old boiler ran between 145 and 180ish.

 

[cancunia]

I don't have any calculator but can tell you that my oil boiler runs up around 190 deg F. And it cycles down to about 160 for a fire call. My old boiler ran between 145 and 180ish.

Many thanks for the info, based on what I've read elsewhere the numbers that you've given seem normal. The reason for my original question is that I tried turning down the water temp and it seemed to use more fuel over an 8 hour period. I think the boiler was running more or less constantly on the lower water setting, trying to heat the room to the room thermostat setting, as opposed to a higher water temp allowing the boiler to modulate it's heat output.
This somehow goes against my thinking that if you drive a car at a steady speed it'll use less less fuel than if you slow down and speed up but maintain the same overall average. Maybe car analogies don't work with heating!

 

[chken]

Hi,
I wondered if there's a view on the best / optimum water temperature in a pellet stove? My MCZ stove can be set to operate between 130 - 175 deg F, but somehow lower settings seem to use more fuel. I guess that the number of radiators will have an effect but wondered if anyone has some kind of calculator or reckoner that can be used?
Thanks

I think the temp you should be setting is determined by the differential between indoors and out. I set my oil burner to 130-160 in the shoulder months, but 160-190 in Winter. There's a happy medium from having your burner cycle on and off too much and not enough. With a wood hydro setup, I don't really know, what does your manual say?

 

[cancunia]

I think the temp you should be setting is determined by the differential between indoors and out. I set my oil burner to 130-160 in the shoulder months, but 160-190 in Winter. There's a happy medium from having your burner cycle on and off too much and not enough. With a wood hydro setup, I don't really know, what does your manual say?

The manual only states that it's possible to adjust the temperature, no guidance is given

 

[chken]

The manual only states that it's possible to adjust the temperature, no guidance is given

You might want to try in the Boiler Room forum where there's a pellet hydronic system expert who regularly checks in.

 

[cancunia]

You might want to try in the Boiler Room forum where there's a pellet hydronic system expert who regularly checks in.

Thanks

 

[Arti]

Just an observation on my part but most boilers that I have worked on seem to have poor combustion below 140 degrees.

 

[Tonyray]

my oil furnace is set 160-180 with 20 degree differential for hot water..
even though I heat with pellets, my boiler doesn't like to be off all the time as the gaskets will end up leaking for me in time by being dormant.
needs to be Hot all the time inside via firing up for domestic hot water few times a day.. hence my reason for not getting an electric hot water tank..

 

[velvetfoot]

I would also agree with moving this to the Boiler Room.

I don't have any experience with this type of combo pellet stove/boiler, but find them interesting.
There was a recent thread on Walltherm, I think it's called, and several people who owned them were discussing their operation.

I went to the MCZ site and looked at the manual for the "Club" 22 hydro model, and no, I didn't see anything specific either. Which model do you have?

I imagine that they all divert some heat to the room via a blower. It seemed that was, maybe, 4kw, of the 22kw total. Maybe other models are different. So, if the water was set at a lower water temperature, the stove could run a longer time to heat the rooms with the radiators, making the room where the stove is located hotter, unless it can vary the output of the fan.

Maybe it's not as efficient when it is modulating down, which it might do more with a lower water temperature, but I'm not sure that would be a big factor.