This is the best electric boiler I have found for radiant floor heat.

All of these heaters are UL 499 compliant and our processes reviewed and tested by an outside testing agency each quarter and use stainless steel heat exchangers and incoloy sheathed elements with titanium sheathing available

The heat exchangers are made of 304 stainless with other stainless alloys available. Our heating elements sheathing material is 800 incoloy. The warranty on electrical parts is 2 years which to our knowledge is the longest in the industry. Our units now meet the no brass rules that start in 2014 for potable water. Those rules are now in effect in Vermont and California but start in other areas of the US in 2014.

  This boiler is specifically built for radiant floor heat.

MINIMUM 125 AMPS HOUSE ELECTRICAL SERVICE!
Specifications:
Weight: 25-38  Lbs. Shipped
Material: Copper Exchanger
Box: White Aluminum Casing
Pipe Size: 3/4" Brass Female IPS
Voltage: 208/240 Single Phase
Max AMPs: 50-70 AMP Double Throw 220 volt breaker)
BTU Output: 40,000 to 80,000
Efficiency: 98.9%
Operating Range: 0-150 PSI
Protection: Dual Thermals

An electrician can repair any of these units on-site.
There is a technician available from 8 AM EST to 7 PM EST to help you troubleshoot and repair any of these heaters.