OAT PB-105 (please explain)

[u4015]

Please expalin the reason one would want to use this feature. I understand that without it the max temp is what it is set to do and the min is no more than an on/off switch. In a nutshell will this save me pellets/$ in the long run or is it an added level of complication for the mother board.

Thanks.
Bob

I realize I may verywell be missing the point of this control so be patient with me. ;-)

 

[taperk600]

being new to this myself, my understanding of what it does is that when the outside temps go up, it allows the boiler to drop to a lower temp before recovering to the max setting, thus using less pellets.

 

[AndrewChurchill]

When a heating system is designed for a house they base the boiler size on the coldest temperature it is likely to see during the heating season. At the coldest temperature the baseboard is going to need 180 F water circulating through it to keep the house warm.

What the OAT does is it measures the outdoor air temp and for every 1 degree above 0F it reduces the maximum boiler temp by one degree until it hits the minimum boiler temp you have set on the control board. For example if the Max temp is set at 180 and it 30F outside the boiler will only heat to 150F.

The theory is since it's warmer outside (In this example 30F) you don't need 180 degree water to keep the house warm, you only need 150 degree water to keep the house warm.

Since you're not heating the boiler to it max and keeping it there you will save fuel.

I use the OAT and it is working very well for me.

I installed a device similar to this on my oil boiler at a duplex I own and it should save me roughly 20% this year. The plumber who installed this device for me has the same model on his boiler and he saved 15% on an 20 year old boiler. He figures I should save at least 20% with my 3 year old Buderus.

 

[u4015]

Thank you Andrew, that makes sense to me.

One final question though. Is 150min and 180max the best temp to work with or is that dependant on the area of the country and the system used.

Bob

 

[AndrewChurchill]

I'd say those settings are personal preference. However, if you are heating your hot water with the PB I wouldn't set the minimum temp below 140.