screwed over need help with boiler

sampson6922

need help with a radiant floor heating system someone else started to put in my garage floor useing a insta hot gas heater they quit working on it after charging me a lot of money and never did get the system to work i finally got it going and it work pretty good but burned a lot of gas i guess because the heater was to small so i want to use a boiler i found a used peerless boiler 95,000 btu non condensing i was hoping some one could help with information on installing a mixing valve and what else so the return cold water doesn't hurt the heater i have put out a lot of money to someone who said they knew what they where doing only to take my money and run when they had a problem my shop is 40x50 with 14 ft ceilings very well insulated i dont know what the heat loss is not a plummer by a long shot but if someone would't mind to help me straighten this out it would be a huge help money is kinda tight i'm disable from a fall a few years back but have some friends to help me with any work i need to do thank u for any help

Leon82

You can grab the slant fin app and do a quick heat loss.

There are lots of things that could be wrong

So you currently have a tankless water heater at the boiler?

GW

Ouch, did you hire riff raf initially? Yes you’re gonna pay full freight if guy #1 bails. Guy #2 is usually skittish.

So you want to put in a bigger boiler and you think that will save you money in fuel? Unless your system is pathetically undersized, that doesn’t make sense to me

Maybe you’re losing heat unknowingly? You’re positive no cold air is entering needlessly? No heated air leaving out the top?

The radiant, you’re well insulated under the slab? No high water tables that can wash your heat away?

Can you get at least one circuit to heat up?

There’s so many things that could be the problem

I’m sorry you get jammed

STEVEusaPA

Wow, one sentence, no punctuation. I couldn't get past the first 2 lines.

sampson6922

no i took the tankless out because it didn't seen to work very well it was 115000 btu but they way the system was done it ran all the time . Don't get me wrong once i got it figured out it kept my shop 65 \70 with opening over head doors 1 or 2 times during the day but burned up 2 tanks of 100 lbs propane in 3 weeks . winter time propane can go up to $ 3.50 a gallon here fuel i can get cheaper at 1.85 a gallon hoping 500 gallons will get me thru most of the winter. I am hoping the oil fired boiler will do a better job i just need a little help on putting in a mixing valve and from what i've been reading the cold return water shouldn't be under 120° . Not sure if i'm right on that but i was told the supply go in the floor temp no higher then 130°. The floor is insulated with a bubble insulation that was out 10 yrs ago. The pex is 1/2 " spaced 8" apart 300 ft runs max outer walls are 225 ft that's about all i can remember from when they installed it and it's all on 1 zone

sampson6922

any help would be appreciated

Leon82

What was the temperature set at on the tankless heater?
It will always run as long as the pump is pushing water thru it. The thermostat would have to shut off the pump thru a switching relay. Maybe you should post a picture of the setup.

Throwing parts at a problem is bad but you are going to throw a boiler at it.

The instructions can be found on a site like supplyhouse and you will get an idea of what's involved before you buy it

GW

If it’s a cast iron boiler you’ll need a 4way mixing valve

Zman

GW's picture is exactly what you should do.
Your slab insulation (specifically the lack of) is your energy problem. You can mitigate somewhat it by using outdoor reset. A taco I series mixer will do that.
As for your energy costs, $3.50/gallon propane=$0.13 KWh electricity= $5.30 gallon oil. Pick your poison....

sampson6922

I will post a pic soon as i can get out their think i was taken advantage for because of my injuries to my head its a shame that someone who is supposed to be a professional would do this to someone but guess it happens everyday

GW

Yes and caution if the 4 way mix gets closed too much the boiler won’t see the expansion tank; relief will drip some water. So you’ll need to pipe the 4way after the expansion IF you fee like you may be nearly closing the valve.

GW

Only riff raf takes money and flees. Now, I have fled when I finished a job, fulfilled my warranty period, because some people are a real pain.