Heating Help

Raypak boiler fire question & replacement piping

Hi there heatinghelp,
Today I was called into look at a Raypak conventional cast iron spark ignition boiler that supplies radiant heat to a few rooms (under the tile). The symptoms were lack of heat after a leak was repaired by some other company.
The boiler, after a proper purge to ensure it wasn't air locked, would not reach over 100*f even with the aquastat set to 180. I see no temp control to prevent the floors from receiving 180*f water (aquastat was set to 180*f) but thats a story for another day. There is a bypass pump (installed upside down) to prevent cold water return shock. The heat exchanger looks to be crystallized from constant cold water return.
Details: 3 zones, 3 pumps, 4 manifolds (one is a split loop providing circulation to two manifolds), one mystery manifold for the second floor hidden, one bypass pump, piped to pump to the boiler.

Being unfamiliar with this boiler, we found a few interesting points.
1, There is a red dial to adjust the flame size. It goes on high fire when turned to its up most setting, then falls down seconds later to small fire.
2, The picture (with arrows) will show that a temp sensor has broken its connection.
3, Many wires internally apear to have burn their shielding off.
4, From the back there was a visible switch on the flue collector in the jacket with a dial showing numbers 140-180.
5, No balancing valves on the tubing and not piped reverse return. (Looked to be the rubber hose material)

The boiler.




Basement manifold.


First floor manifold #1.


First floor manifold #2.


Dissconected sensor.


Three zone pumps, one recirculate pump.


Mystery dial switch on rear of boiler chimney collector.





For now I told the homeowner that I wont repair the boiler due to the bad piping, no temp control for the floors, crystallized heat exchanger. I will offer a replacement, proper pumping away, boiler protection, lower temp floor.

In the end it comes down to these questions.
How would you pipe it? Injection or a mixing valve? What sort of boiler protection would you offer? For now we are leaning to a small cast iron boiler for simplicity & to keep cost down. The heat source must use the natural draft chimney.



Take a look at my other work.
http://i273.photobucket.com/albums/jj231/SpdFreak1/Plumbing/IMG01200-20110112-1551.jpg
http://www.youtube.com/nyplumbingpro

Piping considerations

You probably have non-barrier tubing, so a replacement will require a properly sized  flat plate HX. The system should be cleaned with proper chemicals to remove sludge, prior to commissioning a new boiler.  The piping will depend on the boiler you select. It looks like a good case for a condensing boiler, Most manufacturers' s will illustrate proper piping and mixing valve/pump locations for various applications.

Definitely non barrier tube,,,

In fact, unless my eyes are deceiving me, it is Entran 2, which has been completely recalled, and you missed the boat for any chance of economic recovery... That sucks.

BTW, that boiler isn't a cast iron boiler. It is a copper fin tube boiler with mild steel tube sheets, and it will eventually fail.

The cap tube for the high limit HAS to be reinstalled. The other device is a Modutrol, modulating gas valve, and it too is junk.

Do not touch the tubing, or it will leak. If it leaks, and you call the insurance company, they will exclude the home for any water damage claims.

There isn't a chemical in the world that will straighten out the problems that the tubing is having. It has no oxygen barrier,

Start saving money for a complete system replacement,,,

Sorry for all the bad news.

ME