Combi boiler recommendations

[kj_mustang]

I have read many boiler reviews and posts on forums and still have not found a combination DHW and heat boiler that gets decent recommendations and has good repair track history. I need info on propane units that will do both. I was trying to not use an electric unit for DHW to keep my amp usage down on the building as I have enough in use already. I am building a pole barn that will be very well insulated and I have done several btu calculations. I only need about 30,000 - 35,000 btu for the radiant heat. Any real experience that anyone would like to share about a particular unit would be appreciated.

 

[tdkkart]

If you want radiant floor heat and domestic hot water, for a reasonable price, your best bet is probably seperate units. If all you need is hot water for a sink you can get a small on-demand heater that runs off of 120v and doesn't use alot of power at all.
Once that's taken care of you can look at something like a Tagaki unit for your floor heat.

 

[Jackfre]

My experience has been with the Rinnai E75 and 110 models. I represented them for 20 yrs, retired and now it looks like I'm going to be working with them again, so please note my bias. They are a true mod/con boiler with all the fixin's, outdoor reset, low-loss header, 96% eff. Excellent product. Be aware that your issue with combi's is that they have a plate hx for dhw production. Have your water tested, step one. You may not need water treatment, but it is best to go into any new piece of heating equipment with all the info rather than finding out later. What are your dhw needs? What kind of flow rates do you need? The E75 will make about 2.3gpm at a 70* rise. The 110 will do about 3.2 at 70 rise. If that is sufficient then you are good to go and these will drive a radiant slab like nobody's business. This is not a diy product.

 

[kj_mustang]

Yes, I will be on well water and knew I probably will need to have a water conditioning system. I forgot to add my flow rates to the first post. DHW may need 3-4 gpm, if we move into the barn during home construction. Radiant needs, if I remember it correctly, 1.2 gpm.