Hydronic retro. What would you do?

hydronicsmike

...You'd be best of looking at the 260 Boiler Control with Reset and DHW Features. The 150 maintains a Setpoint only.

Mike

Mike Murray

HW boiler retro. What would you do?

I'm replacing a nat. gas HW heating boiler in a residence and the original is a home built mish-mash of poorly sized mains, zone runs and combinations of baseboard, convector and fan forced unit heaters.

The original boiler was a 133,000 btu copper tube Rheem and I'll be replacing it with a 85,000 btu Hydrotherm Sabre (cast iron sectional). The system itself will take me years to upgrade through attrition but the boiler concern is immediate.

I want to install the boiler with a primary pumped circuit with air purger, feed, LWCO, etc as one continuous, albeit short circuit back into the return and treat the rest of the house system as a secondary pumped circuit tied into the primary. The boiler and primary pump would be controlled by a Tekmar setback controller (probably a #150) and the main room thermostat would control the secondary circ pump. There are 3 other zones controlled by room stats and ancient zone valves (no end switches) and two wild loops that would be part of the secondary.

Anyone care to comment or offer opinions on this setup? Any and all comments appreciated.

Thanks,
Mike

kevin coppinger_4

any particular....

reason you are using the hydrotherm boiler? kpc

Mike Murray

> reason you are using the hydrotherm boiler? kpc



None other than price and availablity. I've never had a problem with any Hydrotherm I've ever installed, although this would be the first "Sabre" model.

kevin coppinger_4

they had a problem..

w/ the burner tubes "rotting" out in say 2-3 yrs.Whats the afue?
Is this natural draft or induced? Piping scheme sounds sound.

Mike Murray

Yeah, I'd heard that with some of their models. These are stainless burners rather than "aluminized steel".
AFUE is 81.6 for the standing pilot, although I wanted to go with the intermittent ignition (82.6)

Thanks for the nod on the piping scheme. I reckon it'll give the boiler longevity and give me some room for future alteration, like perhaps radiant in the rec room instead of a big ol' prop fan unit heater. :-/

Mike Murray

Number mixup

Aaack! Yeah, you're right! I've got my numbers mixed up and thanks for making me look again! Actually it was the 256 I had in mind. There's no DHW as part of this system although I may suggest some radiant to replace some weird old cabinet convectors and unit heaters.