Replacing mechanical systems can take a big bite out of a budget. Even if you don't have a working knowledge of these systems, it's still a good idea to take a closer look at these details:
Check that waste pipes slope enough to flow (as a general guideline, about 1" per 4'). Make sure old plumbing was removed, not just disconnected. Cluttered plumbing, mix-matched materials, and dead-ends may indicate a poor job.
Look for signs of neglected plumbing such as leaky joints and dented/kinked pipes and always check the condition of the water main connection coming into the house.
- visible pipes: no damage, no evidence of leaks, no signs of water stains on materials near pipes, drain pipes slope slightly down towards outlet
- water heater: no signs of rust, vented properly
- water pump: does not short-cycle
- galvanized pipes do not appear to restrict water flow
- drain clean out does not show signs of frequent use
Check the service panel (a.k.a. breaker box). On both fuse and breaker boxes, the main disconnect should have a written rating of amperage (100 - 200 amps). Older homes may be below the 100 amp minimum and need to be updated to code.
See if the lights dim when running an appliance. This indicates a problem with the service load and/or wiring. Make sure wiring appears to be in good condition and there are an adequate number of wall outlets.
- visible wiring: in good condition, no "knob-and-tube" wiring, no exposed splices
- service panel: adequate capacity, all cables attached to panel with cable connectors; fuses or breakers are not overheating
- no aluminum cables for branch circuits
If a house has older forced-air heating/cooling systems, they will eventually need to be replaced. This is a significant expense that should be factored into costs.
Steam heat and radiators can actually be pretty efficient when updated with a new boiler, so don't rule them out. Forced air ducts can also be modified to accept a cooling unit or even a fresh air exchange unit (Energy Recovery Ventilator).
- appears to operate well throughout house
- flues: no open seams, slopes up to outside
- no rust around cooling unit
- no combustion gas odor
- air filter clean
- ductwork in good condition
- no asbestos on steam or water pipes
- separate flues for gas/oil/propane and wood/coal