Old Radiators, New Boiler, and Slime & Sediment

LannyW

My partner and I are planning to use a Triangle Tube Combi condensing boiler to supply 18 big, old radiators, some existing hydronic baseboard (3/4 copper), some new radiant (pex), and DHW.  We are well on our way to designing for the various temperature and volume requirements (but would welcome any bright ideas).  What we’re really wondering about is . . .

 

Will there be a problem with that old black slimy water typical of old systems (think gravity, coal, then oil, then pellets and gas)?   We were leaning toward using a hydraulic separator.  Now we’re wondering if we should provide true mechanical isolation with something such as an indirect tank with the domestic side supplying the radiator zones.  We don't want to compromise the efficiency or functionality of the new system.  Any thoughts on what the old oily residues will do to the heat source heat exchanger in the boiler, or to the mixing valve for the radiant, or to any other new component?  We're planning home runs for the radiators.  Any good ideas for flushing the radiators out? 

 

CMadatMe

Before you make

a final decision. Take a look at Viessmann's new Vitodens 200. I am a big fan of the boiler line and most will same I'm a homer on this but just look at what this boiler will give you over the Triangle.

If you use the Vitdoens 200 you will have to use a low loss header (your hydro seperator). This gives you the seperation from the system and the boiler but there is also a sensor that gives feedback to the boiler to promote condensing without having to give up the efficency you are looking for. The boiler continually looks at incoming gas mixture and pressure adjusting accordingly as gas and pressure change allowing the boiler is to keep firing at it's highest efficiency. The control which is standard will control a high temp curve (your baseboard) plus will run 2 motorized mixing vlvs (radiators and the radiant) on 2 different curves without you having to use a secondary control as you will have to use with the Triangle. You will have to use an indirect with this boiler and the control has priorty in it.  The control is also already set up for phone access if your customer desires to purch the enable control.

The boiler has a better warranty than they triangle and you will find it is a perfect match for the application. I have attached the tech data manual and the low loss header manaul. Drop me a line if you have any other questions.

hot_rod

dirt separators

are a good choice for those systems. I'd valve off flow through the new boilers and run a good hydronic cleaner for a few days. Flush, fill and let the separator work. It can be used with a hydroseparator for more efficient dirt removal than what the hydro separators offer. There are some combo units in larger pipe sizes available.



Soon you will see dual air & dirt in residential sizes also.



They work much better than y-strainers, removing much smaller particles and no pressure drop as they work.



This link explains how they work and where to place them for best results. There are a few brands now on the market.



http://www.caleffi.us/en_US/caleffi/Details/Magazines/pdf/idronics_2_us.pdf



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