Geothermal radiant

GDA

I'm going on the assumption that you are referring to ground source heat pumps as your heat source. When start-up is done in cold weather the flow thru the heat pump may need to be throttled to maintain a head pressure above that of the low pressure cut-out switch, gradually increase flow as the return temperature begins to climb.

Troy_3

geothermal radiant

Seems like a natural. I have two jobs just starting. Wondering what I should watch out for? Anybody have experience? I'm using closed loop system on both jobs. any insight is appreciated.

Andy Michl_2

Make sure that you use a buffer tank to keep the heat pump from short cycling. Just like any heating system longer on/off cycles help the equipment last longer and perform better. Other than that they work great and are very inexpensive to operate.

Troy_3

fuel cost comparison

Does anyone have a fuel cost comparator when using a heat pump vs. nat.gas boiler?

Earthfire

Costs

Your heatpump supplier should have one and wrightsoft has one in their geo hvac package

DanHolohan

Well worth reading

http://www.heatinghelp.com/shopcart/product.cfm?category=11-80

Andy Michl_2

Cost comparrision

If you go to www.hydroheat.com and click on the operating cost work sheet you can compare almost any system at a given fuel cost. I find this to be an excellent calulator. Hope this helps. Andy

Glenn Harrison

Let me add one personal experience.

Check with the heat pump manufactureres specs on the hottest water temp allowed. The company I work for has a customer with a radiant floor basement heated with geothermal, and after having the unit trip a safety I found out that the maximum water temp allowed from the unit is 120°F. So now the system is running cooler than designed and takes for ever to heat the slab.

GDA

Clarification

When start-up is done in cold

> weather the flow thru the heat pump may need to

> be throttled to maintain a head pressure above

> that of the low pressure cut-out switch,

> gradually increase flow as the return temperature

> begins to climb.



A clarification of my statement about throttling the flow thru the heat pump. The flow to the floor system is what needs to be reduced and it is to maintain refigerant suction pressure above that of the low pressure cut-out switch, not maintain head pressure as I stated.