Will pump in my furnace freeze?

kgruber

kgruber

Final Approach
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Skywag
We've been in this house for only 1/2 year. It had a new heat pump and furnace installed 2 years ago. I've tried to ask this of the installers but they are all out on emergency services. (Chehalis floods).

When it is below 32°F........should I worry about this pump or its' pipe freezing? I've never seen a pump like this installed on other similar systems that I've owned.

 
That pump is a drain reservoir for the drip pan below your coil. Over time, if your heat pump is working, that container will fill with water condensing off the coil. Once enough water fills the reservoir, the pump will kick on to empty the reservoir. That cycle is infrequent. Where the drain terminates is an open question. Even outside, the water being pumped out would drain and clear the pipe before it would freeze.
 
just a guess...but the discharge loation is probably above the level of the AC coils...otherwise no need for a pump.
and I'd bet there's a trap in the outlet pipe somewhere that could hold water. That if anything is probably your concern. Maybe also a check valve if there's much vertical run to it...that could hold water above it
I'd guess that it's fairly easy to take the pump apart (the black part out of the red part) and pour any remaining water out...and then basically no water would remain

Side note...wood floor, so I'd want a battery backup on that pump if you're likely ever to leave for extended periods leaving the Air Conditioner running (summer of course)
 
That pump is likely 110. The times I have seen trouble is when debris clogs the pipe to the reservoir, or when the pump fails.
 
Oh, I should also mention, as noted, that pumps out condensation from the AC when it's hot. And, depending on your furnace / humidifier setup, may also pump out condensate from a high efficiency furnace and/or excess water from a flow through humidifier. If your humidifier drains into it, some vinegar every once and a while doesn't hurt to keep the lime deposits down. And in any case, some bleach every once and a while keeps the slime at a minimum.
 
Looks just like mine. The condensate pump itself has never caused problems. There should be a cap on the top, you can dump some more water in it to trip the float and then you can hear it run and figure out where the water goes.

Upstream of it, however, there should be a connection from the AC air handler whoosimacalit. That can get gunked up and overflow. Had to put in a pvc cleanout and blast it out with air.

Downstream of it was some 1/4" copper that ran the length of the house, above the drywall. The other end drains into the utility sink in the laundry room. The copper developed a pinhole leak (apparently the condensate is not neutral pH) that caused it to rain in my furnace room, and later, in the laundry room. After a couple of bodged repairs, I gave up and had it fixed for real by having it replaced with vinyl or pex or whatever they used...
 
My high efficiency gas furnace has a similar drain and pump. The combustion gasses are cooled to the point of condensation by the incoming airflow from the house. Mine pumps to the laundry sink, through vinyl tubing. If my basement dropped below freezing, the pump would freeze, but that could only happen if the furnace had failed, or power lost. Replacing the pump would be the cheapest of my repairs, as all the plumbing would have frozen too.
 
I have a similar setup and have never had a freezing problem, but it will depend on the environment the pipe sees when it exits the house. The environment my pipe sees is Florida.
 
Not a problem for me. Our house was built in 1972 and has gas forced air for heat. What is this heat pump you speak of? :)
 
Shouldn't have any condensation when in heating mode.
 
westrujp said:
Shouldn't have any condensation when in heating mode.
Click to expand...

If I correctly recall the furnace in my last house, it did have a condensate pump. Very high efficiency furnaces have an exhaust temp too low to carry away all of the moisture formed in combustion , so there is some condensation to remove even in heat mode.
 
westrujp said:
Shouldn't have any condensation when in heating mode.
Click to expand...
If it's a high efficiency condensing furnace, there will be condensate when heating, too. My tankless water heater has a condensate drain.
 
GaryM said:
If I correctly recall the furnace in my last house, it did have a condensate pump. Very high efficiency furnaces have an exhaust temp too low to carry away all of the moisture formed in combustion , so there is some condensation to remove even in heat mode.
Click to expand...

Fair enough, depends on if the condensate drain in this case serves the heat pump only, or if the furnace section is above the heat pump, etc...
 
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