ᐅ Evaluation of Quote for Gas/Condensing Boiler Including Solar Thermal System

Hello everyone,
I’m reaching out because I want to upgrade the heating system in my house, built in 1966. It’s an end-of-terrace house with a flat roof.
Currently, it has an oil heating system from 1993. The radiators are standard, although some have the latest control units.
I plan to convert it to gas condensing with solar thermal.
I currently have two offers and would like to hear your feedback on them.
The offers are attached... what do you think?
Offer 1 has already deducted the subsidy (about 40%):

Offer 2 has not deducted the subsidy and additionally charges 1700€ for the hydraulic balancing. This is not shown in the image.

For both offers, the connection fee still needs to be considered (60% of 3000€).
What are your thoughts on this? Other heating systems are unfortunately not an option because they are difficult to retrofit in an older building.

I would go with photovoltaics. It is more cost-effective than solar thermal systems.
Regarding the evaluation of the offers, a specialist will surely provide input.

Solar thermal system removed. Not cost-effective. And the rest, in my opinion, is too expensive.

Hi everyone,
thanks for your replies.

rick2018 schrieb:

I would choose photovoltaics. It’s more cost-effective than solar thermal.
A specialist will probably comment on evaluating the offers.

I can’t go with photovoltaics because I need to replace my heating system, and since 2020 only gas boilers combined with solar thermal are subsidized. I don’t have the budget for photovoltaics. Switching to a gas condensing boiler without solar thermal already costs 9,600€ plus 1,800€ for the connection... the extra cost for solar thermal is therefore 2,000€.

Joedreck schrieb:

Drop solar thermal. It’s not financially worthwhile. And in my opinion, the rest is too expensive.

That sounds interesting, but can you share comparison figures? Dropping solar thermal would only save me 2,000€.

You are the only one who can provide comparison figures. After all, you need to save €2000 (about $2150) with solar thermal first.
I would get an additional, separate quote without solar thermal.
In Quote 1, isn’t there over €6000 (about $6450) net just for the solar thermal system?

It is true that solar thermal systems cost only about 2,000 more, but is that saving really achieved... what do you think? Do you have any experience with this? What would be the typical payback period?