Sawzall Surgery

[heaterman]

I mentioned this job a couple weeks ago and I post these pictures to serve as a classic example of what you get when:
A. the person doing the job has no clue (he was btw a licensed contractor believe it or not)
B. no plan is in place before beginning to solder pipes

Note the yellow tubing. It is pex after a fashion in that it is polyethylene tubing. The problem is that it was made for underground gas service and had no O2 barrier. (just a neighborly heads up to all you proponents of non barrier tube) The Trianco Heatmaker boiler lasted about 3 years before corrosion and sludge caused by the absence of a barrier took their toll.

Drew and I removed everything you see here, abandoned all the loops of non barrier tube and started from scratch with the installation of her Garn. Pics of that to follow.

 

[Morgan]

What a mess!

 

[heaterman]

This novel method of underfloor heating really has me baffled. Not in the sense that it obviously would perform very poorly if at all, but rather that the guy would imagine such a plan would work in the first place.

 

[brad068]

This reminds me of a screen saver I use to have.

 

[Sawyer]

It will be interesting to see an after photo if you have the time. Will they choose under floor or rads?

 

[heaterman]

It will be interesting to see an after photo if you have the time. Will they choose under floor or rads?

We left three loops intact in the basement slab that were done with Wirsbo tubing. That will be more than sufficient to heat the basement. The upstairs is served by a very nice air handler and we have that piped up. All of the underfloor tubing for the main floor has been abandoned.

This house has a heat loss @ design conditions of around 8btu's/ sq ft. The homeowner has had no heat in it at all for the last 2 winters other than 2 1500w electric heaters and a 28,000 btu unvented heater in the basement running as low as it can be set.

The line from the Garn comes into the HX from the left. We basically have a zone pump for the indirect, the air handler and the 3 loops of remaining infloor. Obviously the circs and controls have to be wired up yet in that picture. The only thing still there from the original installation is the "manifold" the first guy put together.

 

[brad068]

Heaterman, Does this set up work well? Looks like there could be some pressure differences @ the return tie ins. Looks like the primary loop is also part secondary in this set up. My mind is seeing close tees instead with the infloor last.

 

[bpirger]

Would it make sense to to plumb the non-O2 barrier tubing through another HX to keep the floors warm? I'd hate to give up my warm floors....or did the poor install not even heat them anyways?

 

[Sawyer]

It will be interesting to see an after photo if you have the time. Will they choose under floor or rads?

This house has a heat loss @ design conditions of around 8btu's/ sq ft. The homeowner has had no heat in it at all for the last 2 winters other than 2 1500w electric heaters and a 28,000 btu unvented heater in the basement running as low as it can be set.

That is really an efficient house! Is this exceptional in your opinion also? What is the design temperature where the house is built?

 

[heaterman]

Heaterman, Does this set up work well? Looks like there could be some pressure differences @ the return tie ins. Looks like the primary loop is also part secondary in this set up. My mind is seeing close tees instead with the infloor last.

You have a good eye for possible piping problems!

It is tough to see but this is not pri/sec piping. There is a gate valve that separates the guzinta from the guzouta on the floor loop manifold right down at the bottom of the picture. If that weren't there to create separation between the supply return we would indeed have jumped out of the frying pan and into the fire on this job. We'd have flow everywhere.
It's the only piece of the original installation that we left intact. Why the guy did it that way instead of using two separate manifolds is beyond me.....but then, there was little about that piping set up that made any sense.

The only part of the system that is pri/sec is where the gas boiler will interface if she ever elects to install one. You can see that on the return piping below and to the right of the Taco air separator. It's a Webstone primary/secondary/purge valve pointed right straight out from the wall with two ball valves soldered on it.

 

[heaterman]

It will be interesting to see an after photo if you have the time. Will they choose under floor or rads?

This house has a heat loss @ design conditions of around 8btu's/ sq ft. The homeowner has had no heat in it at all for the last 2 winters other than 2 1500w electric heaters and a 28,000 btu unvented heater in the basement running as low as it can be set.

That is really an efficient house! Is this exceptional in your opinion also? What is the design temperature where the house is built?

It is extremely efficient and is far from what we normally encounter. Design conditions for that area are 1*f and right around 6900 heating degree days so it's not real tough.