Handyman wrote:

I have a water pump in my basement which is hooked up to an artesian
well. We have had a streak of unusually hot weather here (90+ degrees
with v. high humidity), which has caused the water pump to sweat so
much that condensation drips off of the holding tank, pipes and
fittings. So much water condenses that it creates large pools of water
in my basement. Is there anything that I can do about this?

Sounds like airsealing the basement would help. A fan on the pump will make
more condensation, and dehumidifiers use lots of energy and make unwelcome
heat on 90 F days.

If the pump and tank have Ap ft^2 of surface at temp Tp and the basement air
has dry bulb temp Tb and dew point Tdp, you might build an airtight plastic
film box with Ab ft^2 of surface around the tank and pump and avoid any
condensation if the box wall temp is greater than Tdp, like this, viewed
in a fixed font like Courier:

R2/3 Tdp R4/3
Rp = ---- | Rb = ----
Ap | Ab
|
Tp ---www----------------www-------- Tb
--- I

I = (Tb-Tp)/(Rp+Rb) and Tdp = Tp+IRp makes Ab = 2Ap/((Tb-Tp)/(Tdp-Tp)-1).

For example, Tb = 90 F (460+90 = 550 R) at 70% RH makes
Tdp = 550/(1-550ln(0.7)/9621) = 539 R, ie 539-460 = 79 F.

If the pump and tank have Ap = 25 ft^2 of Tp = 60 F surface,
Ab = 2x25((90-60)/(79-60)-1) = 86.4 ft^2 min,
eg a 2'x3'x8'-tall box.

Nick