Solar assist for a new boiler

[john2459]

I am replacing my 20+ year old boiler with a new more efficient combi type that supplies DHW and baseboard heat.
I would like to be able to pre heat the water coming into the boiler (checked with NTI and that is not a problem) using the solar preheated water for the baseboard heat and the DHW.
I have done the research but can’t find many examples of this type of system.
The solar installer seems this would just be good for the pre heat to the DHW but a $7k pre heater for an on demand DHW seems a bit much.
What I’m asking is should it be possible to utilize the solar hot water to heat (not to operating temp but enough to minimize the cycling of the boiler) in the baseboard heat AND the DHW?
From what I can see if anything I would need another/different water tank with 2 coils vs 1.
Any info, ideas, experience would be very helpful.

The major parts:
3 bed 2 bath 1400 sf rancher in central Colorado
2 adults

Apricus ETC30 Evacuated tube panel.
40.9kBtu/day
4 gpm max flow rate
Rheem Solaraide 81VR80U-T 80 Gal

NTI TX151 C modulating combi boiler

Thanks John

[LucMan]

Your solar system is only rated at 40k Btu per day, definately not enough btu's to be used for heating. A heating system for a house would require that many btu's per hr.
Next baseboard radiation is not designed for low temperature water, most manufacturers don't publish outputs below 140 f. So forget about using this system for space heating.
The solar system you are describing will be more than just a preheater for the domestic HW, it should provide you with enough daily HW for 6-7 months out of the year without any additional input required from the boiler.
An 80 gallon 2 coil tank is recommended for this type of HW application. Use the boiler model without the DHW combination.

[john2459]

LucMan, Thank you. Much appreciated.