non cendensing boiler

[ketas47]

I am done hooking up my boiler(45000 btu non condensing), plumbed boiler outlet to pressure/temp gauge to expansion tank to air elimanator to relief valve to hand valve to 3 speed pump to hand valve to 4 valve manifold(4 loops 230'long each) to floor to return manifold to strainer to pressure/temp gauge to fill valve to inlet to boiler.I am waiting for electrician to hook-up pump to boiler then thermostat.
Garage is 26'x38 2x6 walls 10 ceiling fully insulated
I want to heat it to about 50*
My goal is to have outlet water from boiler @ 120-125 degrees and inlet @ 110 degrees.
I know water should be at 140 returning to boiler or else to it can shorten your boiler life and cost more money for gas.
But I am going to try it and see if it really will cost more.
I dont have to pay for expensive condensating boiler and relays. Plus the extra expenses with technical repairs if needed. Trying to keep it simple , no mixing valve/pump, no relays, etc.
I asked people how much more it will cost to run or how much life it will take off the boilers life and cant get an answer.
If I can keep the water difference 10*-15* I cant believe I would get that much condensate
I paid $150 for boiler and bought everything else @ menards so I dont have much money invested.
What do you think?
I will try this system and then really know if it is efficient or not.
Thanks Live and learn

 

[Jackfre]

A good cast iron boiler is an excellent heating device. They worked for a long time before the mod cons came out. In your system you will need at least a mixing valve on the return to make sure you are not returning really low temp water to the boiler. You need a min of 140F to the boiler return. Thermal shock and corrosion will be the result if you do not do this. For a CI boiler your operating temps are way to low. You should be looking at an operating temp in the 160 range to get your returns right without the mixing valve.

 

[ketas47]

Do you think a mixing valve on my return would get me the temps i need I really shouldnt run my water hotter than 125* in the floor. I posted a new post and might forget the infloor heat this winter and go with a heat exchanger instead.
Thanks

 

[koditten]

Mixing valve is the best way. I use a gate valve that I manually adjust. I'm a cheap sob.

KO

 

[Jackfre]

There are controls and then there are controls. It's like building a race car. Speed costs money. How much do you want to spend. the best sitautioin is to have outdoor reset which will adjust your boiler water temp automatically depending upon outdoor temp. Previous post is correct in that you could have a mixing valve on both the supply side and the return side. Run the boiler at a temp it is happy at and make sure you mix return water temp to satisfy that side. It isn't optimal, but...go back to the race car part.Like you said, you don't have much in this and you may change it and tweek it annually.