System Upgrade Navien vs. Budurus?

sachmo

Thanks in advance for your help.



I am a homeowner with a choice between 2 options and would like to hear some advice/options on them.



I have a 2800 sq ft 1957 split house in NJ with decent insulation, updated windows etc, with natural gas powered AO Smith water heater and a 1973 100K BTU Utica boiler. There are 2 zones of baseboard (1st/Basement and 2nd floor). It has 4 BR, 2 BA, 1 Kit, 1 LR, 1 DR



We had a flood that killed the units and I have 2 quotes with differing technologies.



Quote 1: Navien Combi unit vented to side wall providing heat and DHW, new pumps and other items $6200



Quote 2: Burdurus 100 BTU Bud GC 124/411 gas water boiler and Bud S120 32 gal. indirect HW tank (and pumps etc) $7350



The house will likely be a residential rental, and I would like a reliable, good performing system that will just run. Both installers seem competent and know their materials and craft.



I would lean toward the Navien, but my concerns are maybe:

- not enough power to heat house during very cold spells (0-20F)

- with the on demand DHW be able to support a 5 person family with showers, laundry, etc...

- is this unit and technology mature enough to be reliable and a good performer?

- DWH lag - will i be waiting for DHW everytime i want to wash hands?



The burderus is reputable brand and I have an indirect setup in my own home (munchkin and TT), which basically has unlimited DHW. My concerns are:



- cost, my problem, but it is more expensive

- additional cost if we need to get a chiminey liner (TBD)

- more parts to the system to break.



So, I would appreciate your views on this. I know you wont comment on price.

But any feedback to help me decide would be much appreciated.