Wiring thermostat

tpmcx

Member
Dec 28, 2017
45
Ohio
I need some wiring advice for my hardy outdoor furnace
I have had my hardy for about 15 years and decided to make a change in how its hooked up
I have separated my heat exchanger coil from my furnace airconditioner acoil
I wanted two separate systems and not use my furnace blower when heating with the boiler
I bought a modular blower unit and mounted my heat exchanger in it and tied it into my duct work
My idea was to have two separate systems that could work independent of each other
My issue now in finishing it up is wiring one thermostat to bring ing the blower relay on the modular blower and energizing the pump relay
outside at the wood stove at the same time
I could use a dpdt relay and have the thermostat energize it then use one set of contacts to bring on the blower and the other set to pull
in the pump relay
any one have a better idea?
I never liked the furnace blower pushing air through two a coils at the same time plus I couldn't use my lp furnace while using the outdoor furnace
Thanks in advance
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA
Two coils in one duct shouldn't be an issue, however what you're doing should work fine also. If it's a 120 v. blower with a fan relay then you probably could use the power to the fan to also run the pump, no extra relay needed.
 

tpmcx

Member
Dec 28, 2017
45
Ohio
Sorry have been busy and haven't been on here for a bit
Thank you for the response
I bought a modular blower to use just as a blower and I mounted my water to air exchanger
to it and redid all my old duct work to use it
I have it all working now but need to finish up the last sections of ductwork to the kitchen
So far I am happy with how it is working
I now can use my lp furnace and/or my outdoor furnace heat source at any time
The only issue I have is I can not get the variable speed blower to run at a higher cfm
than it is now
I have the thermostat closing the circuit between RED and GREEN to bring the blower on
I believe by using it this way I can only get one of 4 rpms from the blower with jumper changes
I am not much on electronics so I am not sure what I need to do to make the control board think
this is an air conditioning or heating system so I can get into a higher cam range
I tried jumping Y1 to Y2 and then RED to GREEN but still get the same rpm range
I have a schematic for the unit but I am not much good in understanding it and don't want to ruin a board
experiminting with different connections
the booklet that came with the unit shows that as a cont blower it will only run 1 of 4 rpm ranges
I'm thinking if I connect it as a 2 stage air conditioner may work best for my application
This if I read it right is the thermostat closes R to Y and blower will run at 70% of jumper rpm range
This would keep air flow down as water starts circulating through the heat exchanger
Then R to Y2 closes and fan runs at 100% of selected range
Am I on the right track or looking at this all wrong?
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA
I'd run the W on a heat only thermostat to Y2. This will get you 100% airflow. I doubt you even need a signal to G.
If a few seconds of cold air is an issue put a delay on the wire before it connects to Y2, but run direct to the pump relay.
Any hvac place should have a delay you can use.
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA

I looked this up in a hurry, but basically this is what I was thinking of.
 

tpmcx

Member
Dec 28, 2017
45
Ohio
Thank you E.Yoder
I did play around with it just after I posted this message
I went RED to Y2 (blue/w stripe) and got the blower to run at a higher cfm
I will try W to Y2 as you suggest tomorrow after work and see how that works
At the higher air flow it seems the heat exchanger cools off too much as air temp drops to much
Going to have to find that sweet spot
Thanks again
 

tpmcx

Member
Dec 28, 2017
45
Ohio
Been working on another project and getting back to my furnace/boiler setup
I have a couple issues come up with my heating
My Hardy H2 started acting up,
I thought it developed a water leak but found it is getting combustion air from somewhere and steaming
over.
I resealed the two doors but that hasn't helped
I need to track that issue down before I go further
The second issue I didn't think about is directly above my lp furnace in the ductwork is two take offs too a bathroom and other to a bedroom, when the lp furnace kicks on it supplies too much airflow to these two rooms
I have dampers in them but if I set them for lower airflow it really hurts airflow from the wood stove air handler that is just downstream
in the ductwork for the lp furnace
Not sure how to help this issue
Maybe a deflector right above the plenum in the duct to help redirect the airflow from going straight up to these two rooms
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA
Have you checked back at the fan? A gap or crack there would let it suck a lot of air up the grates.
 

tpmcx

Member
Dec 28, 2017
45
Ohio
Yes I have,I took the fan off to clean and oil it and checked the cork gasket to make sure it was fine
Im going to clean and reseal the clean out door in the back next
The stove sets there and is right on the edge of boiling all the time
Crazy how hard it is to locate these little issues
Its what makes working on stuff interesting
Thanks for your answer,I do appreciate the help
I need to get my ductwork finished up this weekend and tidy up my wiring
I think Ill need to change my thermostat to one with a differential setting ability
My air handler with the water to air heat exchanger wants to cycle too much
It satisfies the thermostat and shuts down just to restart within a minute.
Interesting project but things never work out how you have it thought out in your head
I guess that's why you hire professionals to do this stuff but I like doing hands on projects
 

tpmcx

Member
Dec 28, 2017
45
Ohio
I got some more of my heating system hooked back up
A question I have but can't find an answer thru many searches is what should the air temp be coming out of the registers
in the house?
My water temp into the water/air heat exchanger is running about a steady 165-170 degrees on the inlet and about 30 degrees
lower on the return line
I just wanted to see what the air temp even at the closest register should be
The air I am getting doesn't seen that warm to me so I am curious to what to expect and what do they make to check it?
 

Eureka

Feeling the Heat
Feb 4, 2018
339
NW Wisconsin
I got some more of my heating system hooked back up
A question I have but can't find an answer thru many searches is what should the air temp be coming out of the registers
in the house?
My water temp into the water/air heat exchanger is running about a steady 165-170 degrees on the inlet and about 30 degrees
lower on the return line
I just wanted to see what the air temp even at the closest register should be
The air I am getting doesn't seen that warm to me so I am curious to what to expect and what do they make to check it?
I think 120+ is what I see most getting to. Changes a lot with airflow and duct size, I think.
 

tpmcx

Member
Dec 28, 2017
45
Ohio
My main issue now is getting the return side hooked up
Right now It is just sucking the cool basement air in
I guess its hard to judge much as far as performance yet
Bad thing is I can't find anywheres to buy any ductwork I need other then ordering from Menards
and waiting two weeks to get it
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA
The temp of the air in your return makes a big difference in air temps at the registers. You need some way for the air to circulate too so it doesn't pull outside air in.
 

E Yoder

Feeling the Heat
Jan 27, 2017
492
Floyd, VA
I would agree, 115-130 is pretty normal air temps if your pulling 68 degree return air.
 

tpmcx

Member
Dec 28, 2017
45
Ohio
I t looks like my register temps are running about 90-95 degree but that's with pulling only air from the basement in
Next is to get the return air hooked up to the new modular blower
I think its going to work well when finished
Thanks for the replies