recommendation for a mod/con gas backup boiler?

[kuribo]

have read good things about Viessmann and Triangle...any opinions? Will be used as a backup for my Econoburn 200 and to supply DHW in the summer. Thanks...

 

[cityboy172]

My personal favorite is locinvar knight. Have installed dozens commercially, with very few problems that were actually problems with the boiler.

 

[BoilerMan]

My vote is for the Viessmann, but the Knight and TT are top notch as well. Those are all $$$$ boilers for backup and summer DHW.

Personally I'm not a fan of any combi boiler for DHW, an indirect or HPWH is my choice for summers.

TS

 

[STIHLY DAN]

HTP is another good one, made here in America.

 

[kuribo]

I wouldn't get the combi- I would get the standard boiler and was thinking to use an indirect tank and heat it as a zone from the backup propane boiler in the summer. The heatpump water heater looks interesting but I want to avoid the electricity usage.

 

[BoilerMan]

The heatpump water heater looks interesting but I want to avoid the electricity usage.

Are you off grid? Do you have a really high electric rate?

FWIW: My rate is $0.15 per kWh and the HPWH costs $15 per month to operate in the summer. Trust me onthese numbers I am the electric Nazi!

TS

 

[kuribo]

Do you have any issue with the recharge rate? Seems they are very slow to reheat the water. That would be an issue for me I think. I suppose with propane prices all over, the costs of these electric hpwhs is probably less that a comparable propane unit.

 

[Vizsla]

Viessman, HTP, Lochinvar Knight. What kind of radiant do you have? I only recommend these mod cons if your target operation temps are below 130. Electric for hot water is because you have to not because you want to.

 

[kuribo]

my radiant is all in floor.

Knowing it depends on your local electric and propane rates, in general, are these electric HPWH more economical to operate, gallon of hot water for gallon of hot water, than propane?

 

[timberr]

I have a Munchkin Contender (HTP) and I am very satisfied with it.

 

[mrjohneel]

I'm getting bids from contractors now who are promoting Lochinvar Knight, the Bosch Greenstar (even though it has a coated aluminum heat exchanger which apparently has worked for years in Europe, plus it has a very good warranty), and the Burnham Alpine (which is what National Grid is promoting). The only thing this layman can say is make sure you size it right. My guys are all over the place in terms of BTUs. Some say it doesn't really matter because they modulate; others say that is BS. I'm going with an indirect dWH rather than a combi boiler -- but, my god, it's confusing.

 

[Vizsla]

my radiant is all in floor.

Knowing it depends on your local electric and propane rates, in general, are these electric HPWH more economical to operate, gallon of hot water for gallon of hot water, than propane?

Ok, as long as your infloor supply temps can be kept at the sweet spot (96-115) for the boiler then you can see the 90 plus efficiencies. Good design and a very good installer will make it work like it supposed to.

Well the HP makes 8-9 gallons of tempered water per hour in hot climates, standard electric makes 21 gal/hour, and a gas 100 plus/hr. Very low usage and demand in a hot climate is where a HPWH works as described. It really depends on what fits your needs. But if you have a mod con going in, why not buy just one water heater for the rest of your life. A stainless superstore or similar. If your flow is under 4.5-5gpm a small 20-30 gall will give you endless hot water with .3-.5 degree standby loss.

 

[Vizsla]

Well I'm trying to post a chart lets see if it works. Return Temp, fire rate, vs. Efficiency thermal overall mod con