Boiler repipe with injection

[craig1]

This boiler serves radiant heat in a 2000 square foot basement and a 2 car garage. It was installed when the house was built 3 years ago. the origional contractor (a plumber) did a fairly nice looking job, but the system worked like a pile of garbage. About 20% of the tile floor was 80 degrees and the rest was 65. the boiler return temp was around 70-90 during basement zone operation and 55 degrees during garage zone opperation. surely the boiler didn't like that much.

the customer said they had the origional installer out 5 times on complaints of poor heat, and finally they stopped coming out. 2 other contractors (both plumbers) recommended high dollar repairs, but didn't explain what they were going to do so the homeowner passed them up. one of them left a note on the 1" pipe "put valve here" near the backflow preventer and fill valve. they never told the HO what kind of valve they wanted to put there though

sorry if the pics are kind of hard to see. there was a bunch of stuff preventing me from standing farther back to take them

heres the before pictures:




I tore out all of the new boiler piping and repiped it pumping away, zoned with grundfoss 3 speed circulators and an injection pump controlled by a Tekmar 356 variable speed injection control with outdoor reset.

heres the after pics





By the way, there are a few things that i did the next day that are not in the pictures, they included installing drip legs on the relief valve and backflow preventer, and installing a balancing valve on the injection loop, and tuning the controll parameters after it ran all night.

the customer called a few days later to say that it works great and they cant believe they suffered for 3 years with the old system

[contactme_11]

very nice work! Just curious, what is the tank to the left? An indirect water heater? A mixing station for radiant? i can't tell from the pics.

[craig1]

that thing on the left would be a $6,000 domestic water treatment plant (according to the homowner) it has like 8 filters in it. they have municipal well water and were having some taste and oder problems so they got that thing intstalled. i gues there was extra room on the unistrut so the hung the pipes there. makes it look like its part of the heating system, but its not

[bjd]

Looks good, was there a mixer that you removed between the return and the supply? looks like one was ther, and just wonering if it was a watts mixer, kinda of weird for a radiant job. How do you like the Gronfos 3 speeds, I have heard that they are nice replacements for the 007,0011,and 0012.

I hate it when guys screw these things up and just walk away, some guys just have NO CLUE when it comes to the most basic near boiler pipeing.

I hate to say it a lot of the replacements that I lose to competion is piped with the cirulator on the return, and most of the time with the same circulator supplied by the boiler company.

Its just like the dopes that work at HD, "well this is the only one we sell so it should fit"

BJD

[craig1]

yes there was a Watts mixing valve in the origional piping. it had been cranked all the way up by someone (not the HO) in an attempt to make the system work. But being a 3 way valve, it offered no protection for the boiler against low return temps.

the grundfos 3 speeds are great. i used those because i had no idea as to the length of the radiant loops. amazingly they only cost a couple bucks more than a 1 speed B&G NRF 22 and they are made in USA, not China like the 22